---------------------------------------------------------- Pietenpol-List Digest Archive --- Total Messages Posted Tue 10/20/09: 46 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:51 AM - Re: Re: lift struts for GN-1 /Pietenpol (Tim Willis) 2. 04:51 AM - Prop choices for A-65 (Ryan Mueller) 3. 05:09 AM - Re: Chapter 1218 Pietenpol? (Tim Willis) 4. 06:39 AM - Re: engine turning alum, warping (Jack Phillips) 5. 06:39 AM - Re: Chapter 1218 Pietenpol? (Jack Phillips) 6. 06:56 AM - Re: Re: lift struts for GN-1 /Pietenpol (AMsafetyC@aol.com) 7. 07:10 AM - Re: Chapter 1218 Pietenpol? (Ryan Mueller) 8. 07:11 AM - Re: Prop choices for A-65 (Skip Gadd) 9. 07:11 AM - Re: Prop choices for A-65 (Lagowski Morrow) 10. 07:39 AM - Re: Re: lift struts for GN-1 /Pietenpol (Ryan Mueller) 11. 08:11 AM - Re: Re: lift struts for GN-1 /Pietenpol (AMsafetyC@aol.com) 12. 08:42 AM - Re: Re: lift struts for GN-1 /Pietenpol (Gary Boothe) 13. 09:12 AM - Re: Re: lift struts for GN-1 /Pietenpol (AMsafetyC@aol.com) 14. 09:12 AM - Re: Re: lift struts for GN-1 /Pietenpol (David Paule) 15. 11:13 AM - Re: Re: lift struts for GN-1 /Pietenpol (Ken Howe) 16. 12:20 PM - Re: strut stress (ivan.todorovic) 17. 12:35 PM - Re: lift struts for GN-1 /Pietenpol (Catdesigns) 18. 12:59 PM - Tail feather drain holes (at7000ft) 19. 01:38 PM - Re: Prop choices for A-65 (Jack Phillips) 20. 01:46 PM - Re: strut stress (K5YAC) 21. 01:53 PM - Re: Re: lift struts for GN-1 /Pietenpol (Ken Howe) 22. 01:54 PM - Re: Prop choices for A-65 (Ryan Mueller) 23. 02:04 PM - Skis (Matt Keyes) 24. 02:28 PM - Re: [piet] Re: Chapter 1218 Pietenpol? (Mike Whaley) 25. 02:28 PM - Re: Re: strut stress (Bill Church) 26. 02:40 PM - Re: Re: lift struts for GN-1 /Pietenpol (Mike Tunnicliffe) 27. 02:42 PM - Re: Re: strut stress (Ken Howe) 28. 02:44 PM - Re: strut stress (ivan.todorovic) 29. 02:50 PM - Re: Prop choices for A-65 (Gene Rambo) 30. 03:03 PM - Re: Prop choices for A-65 (Ryan Mueller) 31. 03:27 PM - Re: Re: lift struts for GN-1 /Pietenpol (David Paule) 32. 05:04 PM - Props for A 65 (Gene & Tammy) 33. 05:24 PM - Prop choices for A-65 (helspersew@aol.com) 34. 05:31 PM - Re: Props for A 65 (Tim Willis) 35. 05:42 PM - Re: Props for A 65 (Gary Boothe) 36. 05:52 PM - Re: Prop choices for A-65 (Gary Boothe) 37. 06:45 PM - Re: lift struts for GN-1 /Pietenpol (Bill Church) 38. 06:46 PM - Re: Prop choices for A-65 (Skip Gadd) 39. 07:24 PM - Re: Prop choices for A-65 (Tim Willis) 40. 07:28 PM - Re: Re: lift struts for GN-1 /Pietenpol (Robert Ray) 41. 07:43 PM - Re: Re: strut stress (Clif Dawson) 42. 07:54 PM - Re: Jay Anderson prop (Jeff Boatright) 43. 08:02 PM - Re: Prop choices for A-65 (Dick N.) 44. 08:03 PM - Re: Tail feather drain holes (Dick N.) 45. 08:26 PM - Re: Re: lift struts for GN-1 /Pietenpol this is a long one (AMsafetyC@aol.com) 46. 10:11 PM - Prince Q-tip prop for sale for A-75 w/tapered shaft - 68x42 (Steve Ruse) ________________________________ Message 1 _____________________________________ Time: 03:51:26 AM PST US From: Tim Willis Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol That's right, the jury struts keep the lift struts from buckling in compression. Tim in central TX -----Original Message----- >From: coxwelljon >Sent: Oct 19, 2009 11:46 PM >To: pietenpol-list@matronics.com >Subject: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol > > >Thanks for that explanation. My own understanding of architectural structures tells me that this member is going to be critical in compression. I will work out the angles in cad and measure where the jury struts attach based on the way my wings are built. I believe the main reason for the jury struts is to shorten the L/R ratio for the strut action in compression. > >Thanks again > >-------- >Jon Coxwell >Recycle and preserve the planet > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=268648#268648 > > ________________________________ Message 2 _____________________________________ Time: 04:51:59 AM PST US Subject: Pietenpol-List: Prop choices for A-65 From: Ryan Mueller Good morning all, There will be an A-65-8 making it's way to our shop in a couple of weeks. I am contemplating it's future. It is complete, and should be a runner; however it does not come with a prop. I would prefer to have a wood prop on the Piet. Can those of you that have wood props flying on A-65's on your Pietenpol's comment on the make, size, and pitch that you are running, or you experiences in the past with varying configurations? Thanks much, and have a good morning. Ryan ________________________________ Message 3 _____________________________________ Time: 05:09:30 AM PST US From: Tim Willis Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? A lot of this project is remarkable. Some change in looks certainly comes from the metal construction, which leads to very unfamiliar appearance of much of the project. We are accustomed to wood. Some of the wing looks very familiar, as you would expect on a (mostly?) wooden wing, but even the ribs look a little different. Are they wood? I'd have to spend a lot of time looking at all the details to be able to put my finger on the changes. Almost all of this will be covered up, as on all Piets. The biggest difference in finished appearance will be the much larger VStab and rudder, which is obviously derived bu altered from BP design. Now it seems to overpower the looks of the rest of the plane. That will be less the case when the wings, windshield, and firewall-forward all go on, changing overall visual proportions. Whatever it is, the workmanship looks good. I would have liked to see it before it was covered, to see exactly what they did. Interesting, but any purist would cringe at the changes. I suspect that many of the changes reflect what its builders had previously built, leveraging their experience and skills. I can barely imagine building a Piet this way, with as many departures from customary practice. I don't know how many found or read the chapter's writeup, which states that the chapter had five nearly full-time experienced builders working on it for 3 months. The plan had been to fly the plane to Oshkosh for the 80th anniversary. Lacking that progress in time, they intended to take the project to Oshkosh to show what a Piet's innards looked like, but the EAA HQ was unsupportive of that. Tim in central TX do not archive -----Original Message----- From: helspersew@aol.com Sent: Oct 19, 2009 6:44 PM Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? Dan, I am sitting here scratching my head looking at those pictures. Nothing I see looks like a Pietenpol to me. Am I crazy? This is NOT a Pietenpol. Dan Helsper Poplar Grove, IL. -----Original Message----- From: Dan Yocum Sent: Mon, Oct 19, 2009 11:25 am Subject: Pietenpol-List: Chapter 1218 Pietenpol? Hi all, Anyone on here from EAA Chapter 1218 in Missouri? I just ran across their Pietenpol build pages and am flabbergasted - they started builing on April 28th and covered it in early September! WOW! http://www.eaa1218.org/index.php/chapter-projects/37-pietenpol It's also the biggest vertical stabilizer I've ever seen on a Piet (well, except for that Piet on floats up in Canada). And side doors - it's got side doors! Cheers, Dan -- Dan Yocum Fermilab 630.840.6509 yocum@fnal.gov, http://fermigrid.fnal.gov Fermilab. Just zeros and ones. ==================================== target=_blank>http://www.matronics.com/Navigator?Pietenpol-List ==================================== ://forums.matronics.com ==================================== lank>http://www.matronics.com/contribution ==================================== ________________________________ Message 4 _____________________________________ Time: 06:39:57 AM PST US From: "Jack Phillips" Subject: RE: Pietenpol-List: engine turning alum, warping You don't have to bear down very hard. I was using alclad 2024-T3, and you just want to scuff the alcald alyer, but not penetrate it or you can get corrosion problems later. I don't recall heat being an issue, but understand I did this about 10 years ago. Jack Phillips NX899JP Raleigh, NC _____ From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of shad bell Sent: Monday, October 19, 2009 8:38 PM Subject: Pietenpol-List: engine turning alum, warping Jack, I have messed around with engine turning a couple times with "down time projects" at work. We have 2 inch scotch brite wheels that go in the special arbor, wheel. How do you keep the piece from warping from the localized heat? It seems this makes the aluminum harder, and more likely to crack. My technique probably needs refined I imagine. Just courious, might want to turn something in the future. Shad ______________________________________ ________________________________ Message 5 _____________________________________ Time: 06:39:57 AM PST US From: "Jack Phillips" Subject: RE: Pietenpol-List: Chapter 1218 Pietenpol? I'm not sure it is a Pietenpol. The landing gear strut attach points look more like a Grega than a Piet. Jack Phillips NX899JP Raleigh, NC -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Tim Willis Sent: Tuesday, October 20, 2009 8:00 AM Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? A lot of this project is remarkable. Some change in looks certainly comes from the metal construction, which leads to very unfamiliar appearance of much of the project. We are accustomed to wood. Some of the wing looks very familiar, as you would expect on a (mostly?) wooden wing, but even the ribs look a little different. Are they wood? I'd have to spend a lot of time looking at all the details to be able to put my finger on the changes. Almost all of this will be covered up, as on all Piets. The biggest difference in finished appearance will be the much larger VStab and rudder, which is obviously derived bu altered from BP design. Now it seems to overpower the looks of the rest of the plane. That will be less the case when the wings, windshield, and firewall-forward all go on, changing overall visual proportions. Whatever it is, the workmanship looks good. I would have liked to see it before it was covered, to see exactly what they did. Interesting, but any purist would cringe at the changes. I suspect that many of the changes reflect what its builders had previously built, leveraging their experience and skills. I can barely imagine building a Piet this way, with as many departures from customary practice. I don't know how many found or read the chapter's writeup, which states that the chapter had five nearly full-time experienced builders working on it for 3 months. The plan had been to fly the plane to Oshkosh for the 80th anniversary. Lacking that progress in time, they intended to take the project to Oshkosh to show what a Piet's innards looked like, but the EAA HQ was unsupportive of that. Tim in central TX do not archive -----Original Message----- From: helspersew@aol.com Sent: Oct 19, 2009 6:44 PM Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? Dan, I am sitting here scratching my head looking at those pictures. Nothing I see looks like a Pietenpol to me. Am I crazy? This is NOT a Pietenpol. Dan Helsper Poplar Grove, IL. -----Original Message----- From: Dan Yocum Sent: Mon, Oct 19, 2009 11:25 am Subject: Pietenpol-List: Chapter 1218 Pietenpol? Hi all, Anyone on here from EAA Chapter 1218 in Missouri? I just ran across their Pietenpol build pages and am flabbergasted - they started builing on April 28th and covered it in early September! WOW! http://www.eaa1218.org/index.php/chapter-projects/37-pietenpol It's also the biggest vertical stabilizer I've ever seen on a Piet (well, except for that Piet on floats up in Canada). And side doors - it's got side doors! Cheers, Dan -- Dan Yocum Fermilab 630.840.6509 yocum@fnal.gov, http://fermigrid.fnal.gov Fermilab. Just zeros and ones. =================================== target=_blank>http://www.matronics.com/Navigator?Pietenpol-List =================================== ://forums.matronics.com =================================== lank>http://www.matronics.com/contribution =================================== ________________________________ Message 6 _____________________________________ Time: 06:56:33 AM PST US From: AMsafetyC@aol.com Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Not being an engineer of any sort type or configuration or disciplines, rocket scientist or mathematician. The explanation is great as is sharing the equation. And knowing the compression factors and or forces is a really nice piece of information. However that assumes one knows or can anticipate the loading, which brings me to my question. How do we determine the loading values or amounts such that we are able to compare design and materials yield based upon a calculated or anticipated need of in flight loading ? Naturally that assumes that the need is the exact amount of stress applied to a particular structural member during full and repeated loading? What are the effects of shape, materials, laminations, composites and metals on their ability to support the load and resist failure? For me, not being math savvy, are considered complex concepts and calculations that are well beyond my simple math skills and aerodynamic calculation capabilities. I would like someone to provide a simple but effective way for me and other mathematically challenged builders to determine the efficacy of our material choices and their ability to respond to a range of loads without failure? In short we, correction, I speak for those of us that do not have a death wish but are mathematically challenged and of a mature age who just want to fly a safe aircraft, how do we determine those factors pre test flight rather then post or during test flight activities? I suspect that learning about catastrophic material failure during a test flight is not a good thing and may be subject to screwing up ones entire day. John In a message dated 10/20/2009 12:33:26 A.M. Eastern Daylight Time, tkreiner@gmail.com writes: --> Pietenpol-List message posted by: "tkreiner" Guys, As a Consulting Mechanical Engineer, I'm going to jump in here, and make a few observations, as not all of us have the same background. When a stressed member is being discussed, it might be helpful to add the equations needed so anyone can use them in the future. In the case of the struts being discussed, we have several concepts which, although understood by engineers and those really familiar with the issue being discussed, can become confusing and/or confused. First, the Yield Strength of 4130 is somewhat less than the 95,000 psi given. It turns out that 95,000 psi is generally given as the Ultimate Strength of 4130. The Yield Strength, however, defined to be that level of stress at which permanent deformation (stretching) takes place, is around 75,000 psi. (When doing stress calculations, most engineers will use the Yield Strength, not the Ultimate, or breaking strength. We not only don't want the member to permanently stretch, we damn sure don't want it to break. ) The equation describing the strength of any member in tension, and a limited amount of cases in compression, is: s = P/A, where s is the Yield Strength, P is the load in pounds, and A is the cross-sectional area of the member. In the case of the strut in the discussion, we are looking for the load the member will carry, so we rearrange the equation, then "plug & chug" to get: P = s x A = 75,000 x .149 = 11,175 pounds. This will work very nicely in the case of a member being loaded in tension. If that member is a slender bar, shaft, tube, etc., however, column buckling equations come into play. If the member is a strut at an angle.... we must first apply a little Trig to determine the vector load on the member prior to determining the load carrying capacity of that member. Hope this helps. -------- Tom Kreiner Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268647#268647 ________________________________ Message 7 _____________________________________ Time: 07:10:53 AM PST US Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? From: Ryan Mueller They appear more like Grega, but they're not really even that. At least with the Grega gear, I believe the front landing gear fitting and wing strut fitting are supposed to still be at the same station. They've moved the front gear attach point to just aft of the front wing strut fitting. The basic fuselage structure, in the pics of it before covering, appears roughly similar to the steel tube plans in the F&G manual. Well, from the rear cockpit aft at least. Their lower longerons appear to be straight from the tailpost to the rear wing strut fittings, instead of having the gentle curvature shown in the plans. Then they added doors, and there's the whole issue of the morphadite, cartoonish vertical stab and rudder. I think someone forgot their reading glasses the day they pulled measurements from the plans. It definitely looks to be nice workmanship, especially for having been constructed at an accelerated pace. It is a nice example of lightplane construction that is loosely based on the Pietenpol design, but having it on display at OSH as an example of how a Pietenpol is constructed would be a bit of a stretch. Ryan On Tue, Oct 20, 2009 at 8:24 AM, Jack Phillips wrote: > pietflyr@bellsouth.net> > > I'm not sure it is a Pietenpol. The landing gear strut attach points look > more like a Grega than a Piet. > > Jack Phillips > NX899JP > Raleigh, NC > > -----Original Message----- > From: owner-pietenpol-list-server@matronics.com > [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Tim Willis > Sent: Tuesday, October 20, 2009 8:00 AM > To: pietenpol-list@matronics.com > Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? > > > > A lot of this project is remarkable. > > Some change in looks certainly comes from the metal construction, which > leads to very unfamiliar appearance of much of the project. We are > accustomed to wood. Some of the wing looks very familiar, as you would > expect on a (mostly?) wooden wing, but even the ribs look a little > different. Are they wood? I'd have to spend a lot of time looking at all > the details to be able to put my finger on the changes. > > Almost all of this will be covered up, as on all Piets. The biggest > difference in finished appearance will be the much larger VStab and rudder, > which is obviously derived bu altered from BP design. Now it seems to > overpower the looks of the rest of the plane. That will be less the case > when the wings, windshield, and firewall-forward all go on, changing > overall > visual proportions. > > Whatever it is, the workmanship looks good. I would have liked to see it > before it was covered, to see exactly what they did. Interesting, but any > purist would cringe at the changes. I suspect that many of the changes > reflect what its builders had previously built, leveraging their experience > and skills. I can barely imagine building a Piet this way, with as many > departures from customary practice. > > I don't know how many found or read the chapter's writeup, which states > that > the chapter had five nearly full-time experienced builders working on it > for > 3 months. The plan had been to fly the plane to Oshkosh for the 80th > anniversary. Lacking that progress in time, they intended to take the > project to Oshkosh to show what a Piet's innards looked like, but the EAA > HQ > was unsupportive of that. > Tim in central TX > do not archive > > > -----Original Message----- > From: helspersew@aol.com > Sent: Oct 19, 2009 6:44 PM > To: pietenpol-list@matronics.com > Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? > > > Dan, > > I am sitting here scratching my head looking at those pictures. Nothing I > see looks like a Pietenpol to me. Am I crazy? This is NOT a Pietenpol. > > Dan Helsper > Poplar Grove, IL. > > > -----Original Message----- > From: Dan Yocum > To: pietenpol-list@matronics.com > Sent: Mon, Oct 19, 2009 11:25 am > Subject: Pietenpol-List: Chapter 1218 Pietenpol? > > > > Hi all, > > Anyone on here from EAA Chapter 1218 in Missouri? > > I just ran across their Pietenpol build pages and am flabbergasted - they > started builing on April 28th and covered it in early September! WOW! > > http://www.eaa1218.org/index.php/chapter-projects/37-pietenpol > > It's also the biggest vertical stabilizer I've ever seen on a Piet (well, > except for that Piet on floats up in Canada). > > And side doors - it's got side doors! > > Cheers, > Dan > > -- Dan Yocum > Fermilab 630.840.6509 > yocum@fnal.gov, http://fermigrid.fnal.gov > Fermilab. Just zeros and ones. > > =================================== > target=_blank>http://www.matronics.com/Navigator?Pietenpol-List > =================================== > ://forums.matronics.com > =================================== > lank>http://www.matronics.com/contribution > =================================== > > ________________________________ Message 8 _____________________________________ Time: 07:11:49 AM PST US From: "Skip Gadd" Subject: RE: Pietenpol-List: Prop choices for A-65 Ryan, Have had 2 props on Felix the GN-1, A-65, plane weighs 720 lbs. 1. McCauley Met-L-Prop 74-43. Climbs good can handle pac up to 220 if is not too hot. Cruse at 2150 68 to 70 MPH. Max RPM 2375. 2. Hegy I got from Don E. 72-44 Climbs not as good can handle pac up to 180. Curse at 1950 72 MPH. Max RPM 2150. Interestingly, the plane seems to get 3.8 GPH with ether prop. I would like to have a Sensenich 72-42. Skip ----- Original Message ----- From: Ryan Mueller Sent: 10/20/2009 7:59:17 AM Subject: Pietenpol-List: Prop choices for A-65 Good morning all, There will be an A-65-8 making it's way to our shop in a couple of weeks. I am contemplating it's future. It is complete, and should be a runner; however it does not come with a prop. I would prefer to have a wood prop on the Piet. Can those of you that have wood props flying on A-65's on your Pietenpol's comment on the make, size, and pitch that you are running, or you experiences in the past with varying configurations? Thanks much, and have a good morning. Ryan ________________________________ Message 9 _____________________________________ Time: 07:11:49 AM PST US From: "Lagowski Morrow" Subject: Re: Pietenpol-List: Prop choices for A-65 I have used 2 props, 72x42 with, for me, satisfactory results. A compromise between climb and cruise Note that Sensenich wood props in Catalogs for a 65 Cont. are listed as 72x42 for a std. prop and 72x44 for a cruise prop.--Jim Lagowski, NX221PT ( sometimes known as one Piet) ----- Original Message ----- From: Ryan Mueller To: pietenpol-list@matronics.com Sent: Tuesday, October 20, 2009 7:51 AM Subject: Pietenpol-List: Prop choices for A-65 Good morning all, There will be an A-65-8 making it's way to our shop in a couple of weeks. I am contemplating it's future. It is complete, and should be a runner; however it does not come with a prop. I would prefer to have a wood prop on the Piet. Can those of you that have wood props flying on A-65's on your Pietenpol's comment on the make, size, and pitch that you are running, or you experiences in the past with varying configurations? Thanks much, and have a good morning. Ryan ________________________________ Message 10 ____________________________________ Time: 07:39:59 AM PST US Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol From: Ryan Mueller John, If one is going to depart from the plans in such a way that most don't, for example with the use of round tubing for wing struts instead of streamlined, then the only way to know for sure which size tubing would be suitable is to figure out the math and perform the calculations. You may save money on materials, but you will have to spend the time to figure out what to substitute. Personally I prefer to save the time and fretting, and just go with the plans, or consult the 80 years of empirical knowledge that have been accumulated about how to build a Piet. The plans work, so that ought to be option #1. If you deviate from the plans either because of the need to address a perceived issue or maybe because materials (such as the streamline tubing Bernard had) are no longer available, and you do not want to have to perform the engineering to know for sure whether your change will work, then you ought to just copy what others have done successfully. Maybe they did the calculations, flew it, and it works. Or maybe they just eyeballed it, flew it, and it still worked. Either way someone else bore the risk of test flying the concept for you. Again, if not wanting to do the calculations yourself, I would think that would be the route to go. For what it's worth... :P Have a good day, Ryan On Tue, Oct 20, 2009 at 8:40 AM, wrote: > Not being an engineer of any sort type or configuration or disciplines, > rocket scientist or mathematician. The explanation is great as is sharing > the equation. And knowing the compression factors and or forces is a really > nice piece of information. However that assumes one knows or can anticipate > the loading, which brings me to my question. > > How do we determine the loading values or amounts such that we are able to > compare design and materials yield based upon a calculated or anticipated > need of in flight loading ? Naturally that assumes that the need is the > exact amount of stress applied to a particular structural member during full > and repeated loading? What are the effects of shape, materials, laminations, > composites and metals on their ability to support the load and resist > failure? > > For me, not being math savvy, are considered complex concepts and > calculations that are well beyond my simple math skills and aerodynamic > calculation capabilities. I would like someone to provide a simple but > effective way for me and other mathematically challenged builders to > determine the efficacy of our material choices and their ability to respond > to a range of loads without failure? > > In short we, correction, I speak for those of us that do not have a death > wish but are mathematically challenged and of a mature age who just want to > fly a safe aircraft, how do we determine those factors pre test flight > rather then post or during test flight activities? I suspect that learning > about catastrophic material failure during a test flight is not a good thing > and may be subject to screwing up ones entire day. > > John > > In a message dated 10/20/2009 12:33:26 A.M. Eastern Daylight Time, > tkreiner@gmail.com writes: > > > Guys, > > As a Consulting Mechanical Engineer, I'm going to jump in here, and make a > few observations, as not all of us have the same background. > > When a stressed member is being discussed, it might be helpful to add the > equations needed so anyone can use them in the future. In the case of the > struts being discussed, we have several concepts which, although understood > by engineers and those really familiar with the issue being discussed, can > become confusing and/or confused. > > First, the Yield Strength of 4130 is somewhat less than the 95,000 psi > given. It turns out that 95,000 psi is generally given as the Ultimate > Strength of 4130. The Yield Strength, however, defined to be that level of > stress at which permanent deformation (stretching) takes place, is around > 75,000 psi. (When doing stress calculations, most engineers will use the > Yield Strength, not the Ultimate, or breaking strength. We not only don't > want the member to permanently stretch, we damn sure don't want it to break. > ) > > The equation describing the strength of any member in tension, and a > limited amount of cases in compression, is: > > s = P/A, where s is the Yield Strength, P is the load in pounds, and > A is the cross-sectional area of the member. > > In the case of the strut in the discussion, we are looking for the load the > member will carry, so we rearrange the equation, then "plug & chug" to get: > > P = s x A = 75,000 x .149 = 11,175 pounds. > > This will work very nicely in the case of a member being loaded in > tension. If that member is a slender bar, shaft, tube, etc., however, > column buckling equations come into play. > > If the member is a strut at an angle.... we must first apply a little Trig > to determine the vector load on the member prior to determining the load > carrying capacity of that member. > > Hope this helps. > > -------- > Tom Kreiner > > > Read this topic online here: > > > http://forums.matronics.com/viewtopic.php?p=268647#268647============================================== > - MATRONICS WEB FORUMS > ================================================ - List > Contribution Web Site sp; > ================================================== > > > * > > * > > ________________________________ Message 11 ____________________________________ Time: 08:11:08 AM PST US From: AMsafetyC@aol.com Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Ryan, Thanks for the info. Actually the question was more to what are the calculations in a simple format. I will spend the time doing them if I knew what to do. Although being an admitted plan deviate offender, motivated,not for money or weight but for style and appearance preferences. I really wasn't asking for someone to do my work for me but rather to point me in the right direction with an equation that I can use myself or with little coaching to make those calculations for my own theoretical piece of mind. As a safety professional for more than 30 years in the discipline and 15 or so in consulting I have always advocated a simple but effective operational model, " never expect someone else to do what you are not willing to do yourself". The philosophy has served me well and has protected many people from accident, injury, occupational illness and the inadvertent acts or errant and emotionally unstable individuals. But still not an engineer, rocket scientist, mathematical genius or marathon runner, always a good idea to know and live within ones physical and intellectual limitations. John In a message dated 10/20/2009 10:40:41 A.M. Eastern Daylight Time, rmueller23@gmail.com writes: John, If one is going to depart from the plans in such a way that most don't, for example with the use of round tubing for wing struts instead of streamlined, then the only way to know for sure which size tubing would be suitable is to figure out the math and perform the calculations. You may save money on materials, but you will have to spend the time to figure out what to substitute. Personally I prefer to save the time and fretting, and just go with the plans, or consult the 80 years of empirical knowledge that have been accumulated about how to build a Piet. The plans work, so that ought to be option #1. If you deviate from the plans either because of the need to address a perceived issue or maybe because materials (such as the streamline tubing Bernard had) are no longer available, and you do not want to have to perform the engineering to know for sure whether your change will work, then you ought to just copy what others have done successfully. Maybe they did the calculations, flew it, and it works. Or maybe they just eyeballed it, flew it, and it still worked. Either way someone else bore the risk of test flying the concept for you. Again, if not wanting to do the calculations yourself, I would think that would be the route to go. For what it's worth... :P Have a good day, Ryan On Tue, Oct 20, 2009 at 8:40 AM, <_AMsafetyC@aol.com_ (mailto:AMsafetyC@aol.com) > wrote: Not being an engineer of any sort type or configuration or disciplines, rocket scientist or mathematician. The explanation is great as is sharing the equation. And knowing the compression factors and or forces is a really nice piece of information. However that assumes one knows or can anticipate the loading, which brings me to my question. How do we determine the loading values or amounts such that we are able to compare design and materials yield based upon a calculated or anticipated need of in flight loading ? Naturally that assumes that the need is the exact amount of stress applied to a particular structural member during full and repeated loading? What are the effects of shape, materials, laminations, composites and metals on their ability to support the load and resist failure? For me, not being math savvy, are considered complex concepts and calculations that are well beyond my simple math skills and aerodynamic calculation capabilities. I would like someone to provide a simple but effective way for me and other mathematically challenged builders to determine the efficacy of our material choices and their ability to respond to a range of loads without failure? In short we, correction, I speak for those of us that do not have a death wish but are mathematically challenged and of a mature age who just want to fly a safe aircraft, how do we determine those factors pre test flight rather then post or during test flight activities? I suspect that learning about catastrophic material failure during a test flight is not a good thing and may be subject to screwing up ones entire day. John In a message dated 10/20/2009 12:33:26 A.M. Eastern Daylight Time, _tkreiner@gmail.com_ (mailto:tkreiner@gmail.com) writes: (mailto:tkreiner@gmail.com) > Guys, As a Consulting Mechanical Engineer, I'm going to jump in here, and make a few observations, as not all of us have the same background. When a stressed member is being discussed, it might be helpful to add the equations needed so anyone can use them in the future. In the case of the struts being discussed, we have several concepts which, although understood by engineers and those really familiar with the issue being discussed, can become confusing and/or confused. First, the Yield Strength of 4130 is somewhat less than the 95,000 psi given. It turns out that 95,000 psi is generally given as the Ultimate Strength of 4130. The Yield Strength, however, defined to be that level of stress at which permanent deformation (stretching) takes place, is around 75,000 psi. (When doing stress calculations, most engineers will use the Yield Strength, not the Ultimate, or breaking strength. We not only don't want the member to permanently stretch, we damn sure don't want it to break. ) The equation describing the strength of any member in tension, and a limited amount of cases in compression, is: s = P/A, where s is the Yield Strength, P is the load in pounds, and A is the cross-sectional area of the member. In the case of the strut in the discussion, we are looking for the load the member will carry, so we rearrange the equation, then "plug & chug" to get: P = s x A = 75,000 x .149 = 11,175 pounds. This will work very nicely in the case of a member being loaded in tension. If that member is a slender bar, shaft, tube, etc., however, column buckling equations come into play. If the member is a strut at an angle.... we must first apply a little Trig to determine the vector load on the member prior to determining the load carrying capacity of that member. Hope this helps. -------- Tom Kreiner Read this topic online here: _http://forums.matronics.com/viewtopic.php?p=268647#268647================= ====_ (http://forums.matronics.com/viewtopic.php?p=268647#268647======================) Use the ties Day ======================= - MATRONICS WEB FORUMS ======================= - List Contribution Web Site sp; " target="_blank">http://www.matronics.com/Navigator?Pietenpol-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution (http://www.matronics.com/Navigator?Pietenpol-List) (http://www.matronics.com/contribution) ________________________________ Message 12 ____________________________________ Time: 08:42:31 AM PST US From: "Gary Boothe" Subject: RE: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol John, I'm with you. I am also a "deviate" for the purpose of style and appearance (for my Piet, that is). It would be very nice to have all the math and engineering to back up my ideas (wood cabanes and struts). Clif Dawson sent me some interesting calc's that confirmed that wood cabanes were indeed well within the safe limits. But I know just enough to be dangerous, such as: What are the effects of side-ways loads? Compression? What are the contributions of the cables to compliment the struts? The latter alone brings up a whole bunch of other calculations, merely showing that the struts certainly do not act alone. In the end, I followed Ryan's sage advice and just copied what has shown to be successful. Too bad I haven't followed that same advice on the financial end. My model is: Buy high.sell cheap! Someday it may pay off - who knows? Gary Boothe Cool, Ca. Pietenpol WW Corvair Conversion, mounted Tail done, Fuselage on gear (15 ribs down.) _____ From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of AMsafetyC@aol.com Sent: Tuesday, October 20, 2009 8:08 AM Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Ryan, Thanks for the info. Actually the question was more to what are the calculations in a simple format. I will spend the time doing them if I knew what to do. Although being an admitted plan deviate offender, motivated,not for money or weight but for style and appearance preferences. I really wasn't asking for someone to do my work for me but rather to point me in the right direction with an equation that I can use myself or with little coaching to make those calculations for my own theoretical piece of mind. As a safety professional for more than 30 years in the discipline and 15 or so in consulting I have always advocated a simple but effective operational model, " never expect someone else to do what you are not willing to do yourself". The philosophy has served me well and has protected many people from accident, injury, occupational illness and the inadvertent acts or errant and emotionally unstable individuals. But still not an engineer, rocket scientist, mathematical genius or marathon runner, always a good idea to know and live within ones physical and intellectual limitations. John In a message dated 10/20/2009 10:40:41 A.M. Eastern Daylight Time, rmueller23@gmail.com writes: John, If one is going to depart from the plans in such a way that most don't, for example with the use of round tubing for wing struts instead of streamlined, then the only way to know for sure which size tubing would be suitable is to figure out the math and perform the calculations. You may save money on materials, but you will have to spend the time to figure out what to substitute. Personally I prefer to save the time and fretting, and just go with the plans, or consult the 80 years of empirical knowledge that have been accumulated about how to build a Piet. The plans work, so that ought to be option #1. If you deviate from the plans either because of the need to address a perceived issue or maybe because materials (such as the streamline tubing Bernard had) are no longer available, and you do not want to have to perform the engineering to know for sure whether your change will work, then you ought to just copy what others have done successfully. Maybe they did the calculations, flew it, and it works. Or maybe they just eyeballed it, flew it, and it still worked. Either way someone else bore the risk of test flying the concept for you. Again, if not wanting to do the calculations yourself, I would think that would be the route to go. For what it's worth... :P Have a good day, Ryan On Tue, Oct 20, 2009 at 8:40 AM, wrote: Not being an engineer of any sort type or configuration or disciplines, rocket scientist or mathematician. The explanation is great as is sharing the equation. And knowing the compression factors and or forces is a really nice piece of information. However that assumes one knows or can anticipate the loading, which brings me to my question. How do we determine the loading values or amounts such that we are able to compare design and materials yield based upon a calculated or anticipated need of in flight loading ? Naturally that assumes that the need is the exact amount of stress applied to a particular structural member during full and repeated loading? What are the effects of shape, materials, laminations, composites and metals on their ability to support the load and resist failure? For me, not being math savvy, are considered complex concepts and calculations that are well beyond my simple math skills and aerodynamic calculation capabilities. I would like someone to provide a simple but effective way for me and other mathematically challenged builders to determine the efficacy of our material choices and their ability to respond to a range of loads without failure? In short we, correction, I speak for those of us that do not have a death wish but are mathematically challenged and of a mature age who just want to fly a safe aircraft, how do we determine those factors pre test flight rather then post or during test flight activities? I suspect that learning about catastrophic material failure during a test flight is not a good thing and may be subject to screwing up ones entire day. John In a message dated 10/20/2009 12:33:26 A.M. Eastern Daylight Time, tkreiner@gmail.com writes: Guys, As a Consulting Mechanical Engineer, I'm going to jump in here, and make a few observations, as not all of us have the same background. When a stressed member is being discussed, it might be helpful to add the equations needed so anyone can use them in the future. In the case of the struts being discussed, we have several concepts which, although understood by engineers and those really familiar with the issue being discussed, can become confusing and/or confused. First, the Yield Strength of 4130 is somewhat less than the 95,000 psi given. It turns out that 95,000 psi is generally given as the Ultimate Strength of 4130. The Yield Strength, however, defined to be that level of stress at which permanent deformation (stretching) takes place, is around 75,000 psi. (When doing stress calculations, most engineers will use the Yield Strength, not the Ultimate, or breaking strength. We not only don't want the member to permanently stretch, we damn sure don't want it to break. ) The equation describing the strength of any member in tension, and a limited amount of cases in compression, is: s = P/A, where s is the Yield Strength, P is the load in pounds, and A is the cross-sectional area of the member. In the case of the strut in the discussion, we are looking for the load the member will carry, so we rearrange the equation, then "plug & chug" to get: P = s x A = 75,000 x .149 = 11,175 pounds. This will work very nicely in the case of a member being loaded in tension. If that member is a slender bar, shaft, tube, etc., however, column buckling equations come into play. If the member is a strut at an angle.... we must first apply a little Trig to determine the vector load on the member prior to determining the load carrying capacity of that member. Hope this helps. -------- Tom Kreiner Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268647#268647================== == Use the ties Day ======================= - MATRONICS WEB FORUMS ======================= - List Contribution Web Site sp; " target="_blank">http://www.matronics.com/Navigator?Pietenpol-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution =================================== t href="http://www.matronics.com/Navigator?Pietenpol-List">http://www.matronic s.com/Navigator?Pietenpol-List =================================== ms.matronics.com/">http://forums.matronics.com =================================== tp://www.matronics.com/contribution">http://www.matronics.com/contribution =================================== ________________________________ Message 13 ____________________________________ Time: 09:12:42 AM PST US From: AMsafetyC@aol.com Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Gary, That's the flaw in the logic, its buy high, sell low and make it up in volume! Actually I am using wood for the lift struts, cabanes and landing gear laminated with metal inserts at connection points that are slightly more stout than streamline tubing. There are some of those flying so empirical information may be available I again would like to see how those values are calculated for my own edification and piece of mind. That being said they look great! I have pics of the lift struts and landing gear, not great looking form th e pic but impressive in person. The cabanes have stainless tubing embedded to add metallic strength but also to conceal utilities, plumbing and wiri ng. got to reduce the drag hide the junk and build a more attractive cleaner piet. All the exterior wood is being finished by that polyurethane top coat I bought from Rick, wow that stuff is really nice and with a number of coats I suspect it will be bullet proof. My spray technique and paint area is stil l in need of technique perfection and technological advancements but that again is an in time issue. for the moment I am getting a good coat on the wood to protect of from shop hazards, oils colorants and greasy fingered grandson shop assistants who at the ripe old age of 4.999 years will more then likely insist upon being awarded the repairman's certificate.. John In a message dated 10/20/2009 11:43:05 A.M. Eastern Daylight Time, gboothe5@comcast.net writes: John, I=99m with you. I am also a =9Cdeviate=9D for the purpo se of style and appearance (for my Piet, that is). It would be very nice to have all the math and engineering to back up my ideas (wood cabanes and struts). Clif Dawson se nt me some interesting calc=99s that confirmed that wood cabanes were indeed well within the safe limits. But I know just enough to be dangerous, such as: What are the effects of side-ways loads? Compression? What are the contributions of the cables to compliment the struts? The latter alone br ings up a whole bunch of other calculations, merely showing that the struts certainly do not act alone. In the end, I followed Ryan=99s sage advice and just copied what ha s shown to be successful. Too bad I haven=99t followed that same advice on the financial end. My model is: Buy highsell cheap! Someday it may pay off =93 who knows? Gary Boothe Cool, Ca. Pietenpol WW Corvair Conversion, mounted Tail done, Fuselage on gear (15 ribs down) ____________________________________ From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of AMsafetyC @aol.com Sent: Tuesday, October 20, 2009 8:08 AM Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Ryan, Thanks for the info. Actually the question was more to what are the calculations in a simple format. I will spend the time doing them if I knew what to do. Although being an admitted plan deviate offender, motivated,not for money or weight but for style and appearance preferences. I really wasn't askin g for someone to do my work for me but rather to point me in the right direction with an equation that I can use myself or with little coaching to make those calculations for my own theoretical piece of mind. As a safety professional for more than 30 years in the discipline and 15 or so in consulting I have always advocated a simple but effective operational model, " never expect someone else to do what you are not wil ling to do yourself". The philosophy has served me well and has protected many peopl e from accident, injury, occupational illness and the inadvertent acts or errant and emotionally unstable individuals. But still not an engineer, rocket scientist, mathematical genius or marathon runner, always a good idea to know and live within ones physical and intellectual limitations. John In a message dated 10/20/2009 10:40:41 A.M. Eastern Daylight Time, rmueller23@gmail.com writes: John, If one is going to depart from the plans in such a way that most don't, for example with the use of round tubing for wing struts instead of streamlined, then the only way to know for sure which size tubing would be suitable is to figure out the math and perform the calculations. You may save mone y on materials, but you will have to spend the time to figure out what to substitute. Personally I prefer to save the time and fretting, and just go with the plans, or consult the 80 years of empirical knowledge that have been accumulated about how to build a Piet. The plans work, so that ought to be option #1. If you deviate from the plans either because of the need to address a perceived issue or maybe because materials (such as the streamline tubing Bernard had) are no longer available, and you do not want to have to perf orm the engineering to know for sure whether your change will work, then you ought to just copy what others have done successfully. Maybe they did the calculations, flew it, and it works. Or maybe they just eyeballed it, fle w it, and it still worked. Either way someone else bore the risk of test flying the concept for you. Again, if not wanting to do the calculations yoursel f, I would think that would be the route to go. For what it's worth... :P Have a good day, Ryan On Tue, Oct 20, 2009 at 8:40 AM, <_AMsafetyC@aol.com_ (mailto:AMsafetyC@aol.com) > wrote: Not being an engineer of any sort type or configuration or disciplines, rocket scientist or mathematician. The explanation is great as is sharing the equation. And knowing the compression factors and or forces is a really nice piece of information. However that assumes one knows or can anticipa te the loading, which brings me to my question. How do we determine the loading values or amounts such that we are able to compare design and materials yield based upon a calculated or anticipate d need of in flight loading ? Naturally that assumes that the need is the exact amount of stress applied to a particular structural member during full and repeated loading? What are the effects of shape, materials, laminations, composites and metals on their ability to support the load and resist failure? For me, not being math savvy, are considered complex concepts and calculations that are well beyond my simple math skills and aerodynamic calculation capabilities. I would like someone to provide a simple but effective way for me and other mathematically challenged builders to determine the efficacy of our material choices and their ability to respond to a range of loads without failure? In short we, correction, I speak for those of us that do not have a death wish but are mathematically challenged and of a mature age who just want to fly a safe aircraft, how do we determine those factors pre test flight rather then post or during test flight activities? I suspect that learni ng about catastrophic material failure during a test flight is not a good th ing and may be subject to screwing up ones entire day. John In a message dated 10/20/2009 12:33:26 A.M. Eastern Daylight Time, _tkreiner@gmail.com_ (mailto:tkreiner@gmail.com) writes: --> Pietenpol-List message posted by: "tkreiner" <_tkreiner@gmail.com_ (mailto:tkreiner@gmail.com) > Guys, As a Consulting Mechanical Engineer, I'm going to jump in here, and make a few observations, as not all of us have the same background. When a stressed member is being discussed, it might be helpful to add the equations needed so anyone can use them in the future. In the case of th e struts being discussed, we have several concepts which, although understood by engineers and those really familiar with the issue being di scussed, can become confusing and/or confused. First, the Yield Strength of 4130 is somewhat less than the 95,000 psi given. It turns out that 95,000 psi is generally given as the Ultimate Strength of 4130. The Yield Strength, however, defined to be that level of stress at which permanent deformation (stretching) takes place, is around 75,000 psi. (When doing stress calculations, most engineers will use the Yield Strength, not the Ultimate, or breaking strength. We not only don't want the member to permanently stretch, we damn sure don't want it to break. ) The equation describing the strength of any member in tension, and a limited amount of cases in compression, is: s = P/A, where s is the Yield Strength, P is the load in pounds, and A is the cross-sectional area of the member. In the case of the strut in the discussion, we are looking for the load the member will carry, so we rearrange the equation, then "plug & chug" to get: P = s x A = 75,000 x .149 = 11,175 pounds. This will work very nicely in the case of a member being loaded in tension. If that member is a slender bar, shaft, tube, etc., however, column buckling equations come into play. If the member is a strut at an angle.... we must first apply a little Tri g to determine the vector load on the member prior to determining the load carrying capacity of that member. Hope this helps. -------- Tom Kreiner Read this topic online here: _http://forums.matronics.com/viewtopic.php?p=268647#268647==== ============= ====_ (http://forums.matronics.com/viewtopic.php?p=268647#268647==== ==================) Use the ties Day ================== ===== - MATRONICS WEB FORUMS ======================= - List Contribution Web Site sp; " target="_blank">http://www.matronics.com/Navigator?Pietenpol-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution ======================== =========== t href="http://www.matronics.com/Navigator?Pietenpol-List">http://www.matr onics.com/Navigator?Pietenpol-List ======================== =========== ms.matronics.com/">http://forums.matronics.com ======================== =========== tp://www.matronics.com/contribution">http://www.matronics.com/contribution ======================== =========== http://www.matronics.com/Navigator?Pietenpol-List http://forums.matronics.com http://www.matronics.com/contribution ======================== ============ (http://www.matronics.com/Navigator?Pietenpol-List) ======================== ============ ======================== ============ (http://www.matronics.com/contribution) ======================== ============ ________________________________ Message 14 ____________________________________ Time: 09:12:42 AM PST US From: "David Paule" Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Words of wisdom! David Paule ----- Original Message ----- From: Ryan Mueller To: pietenpol-list@matronics.com Sent: Tuesday, October 20, 2009 8:30 AM Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol John, If one is going to depart from the plans in such a way that most don't, for example with the use of round tubing for wing struts instead of streamlined, then the only way to know for sure which size tubing would be suitable is to figure out the math and perform the calculations. You may save money on materials, but you will have to spend the time to figure out what to substitute. Personally I prefer to save the time and fretting, and just go with the plans, or consult the 80 years of empirical knowledge that have been accumulated about how to build a Piet. The plans work, so that ought to be option #1. If you deviate from the plans either because of the need to address a perceived issue or maybe because materials (such as the streamline tubing Bernard had) are no longer available, and you do not want to have to perform the engineering to know for sure whether your change will work, then you ought to just copy what others have done successfully. Maybe they did the calculations, flew it, and it works. Or maybe they just eyeballed it, flew it, and it still worked. Either way someone else bore the risk of test flying the concept for you. Again, if not wanting to do the calculations yourself, I would think that would be the route to go. For what it's worth... :P Have a good day, Ryan On Tue, Oct 20, 2009 at 8:40 AM, wrote: Not being an engineer of any sort type or configuration or disciplines, rocket scientist or mathematician. The explanation is great as is sharing the equation. And knowing the compression factors and or forces is a really nice piece of information. However that assumes one knows or can anticipate the loading, which brings me to my question. How do we determine the loading values or amounts such that we are able to compare design and materials yield based upon a calculated or anticipated need of in flight loading ? Naturally that assumes that the need is the exact amount of stress applied to a particular structural member during full and repeated loading? What are the effects of shape, materials, laminations, composites and metals on their ability to support the load and resist failure? For me, not being math savvy, are considered complex concepts and calculations that are well beyond my simple math skills and aerodynamic calculation capabilities. I would like someone to provide a simple but effective way for me and other mathematically challenged builders to determine the efficacy of our material choices and their ability to respond to a range of loads without failure? In short we, correction, I speak for those of us that do not have a death wish but are mathematically challenged and of a mature age who just want to fly a safe aircraft, how do we determine those factors pre test flight rather then post or during test flight activities? I suspect that learning about catastrophic material failure during a test flight is not a good thing and may be subject to screwing up ones entire day. John In a message dated 10/20/2009 12:33:26 A.M. Eastern Daylight Time, tkreiner@gmail.com writes: Guys, As a Consulting Mechanical Engineer, I'm going to jump in here, and make a few observations, as not all of us have the same background. When a stressed member is being discussed, it might be helpful to add the equations needed so anyone can use them in the future. In the case of the struts being discussed, we have several concepts which, although understood by engineers and those really familiar with the issue being discussed, can become confusing and/or confused. First, the Yield Strength of 4130 is somewhat less than the 95,000 psi given. It turns out that 95,000 psi is generally given as the Ultimate Strength of 4130. The Yield Strength, however, defined to be that level of stress at which permanent deformation (stretching) takes place, is around 75,000 psi. (When doing stress calculations, most engineers will use the Yield Strength, not the Ultimate, or breaking strength. We not only don't want the member to permanently stretch, we damn sure don't want it to break. ) The equation describing the strength of any member in tension, and a limited amount of cases in compression, is: s = P/A, where s is the Yield Strength, P is the load in pounds, and A is the cross-sectional area of the member. In the case of the strut in the discussion, we are looking for the load the member will carry, so we rearrange the equation, then "plug & chug" to get: P = s x A = 75,000 x .149 = 11,175 pounds. This will work very nicely in the case of a member being loaded in tension. If that member is a slender bar, shaft, tube, etc., however, column buckling equations come into play. If the member is a strut at an angle.... we must first apply a little Trig to determine the vector load on the member prior to determining the load carrying capacity of that member. Hope this helps. -------- Tom Kreiner Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268647#268647===== ================ Use the ties Day ======================= - MATRONICS WEB FORUMS ======================= - List Contribution Web Site sp; " target="_blank">http://www.matronics.com/Navigator?Pietenpol-List tp://forums.matronics.com _blank">http://www.matronics.com/contribution ________________________________ Message 15 ____________________________________ Time: 11:13:15 AM PST US Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol From: Ken Howe I'd like to add to Tom's engineering discourse. Some this is from back (OK, waaay back) when I was studying for my Aero degree. For a complete structural analysis of aircraft you have to understand your component strengths for both the yield and ultimate strengths. All aircraft have to be designed to some limit load factor. For 'normal' category aircraft that is +3.8 g's and -1.52 g's (those numbers come from a link I just looked up.) The FAA's certification standards require that an additional safety factor of 1.5 be met. So to simplify, the structure (all parts, fittings and fasteners) is designed so that all the parts stay under the yield strength at required limit loads (+3.8, -1.52). To meet the 1.5 safety factor the loads must be recalculated at +5.9g, -2.28g. These loads can exceed the material yield strength but cannot exceed the ultimate strength. Each material is different in that the spread between yield and ultimate varies greatly as a percentage of the strength. For instance, for most woods, the difference between yield and ultimate is pretty small. You apply a load and not much happens until suddenly it breaks. At any time until it breaks you can relax the load and the piece returns to it's original form (i.e. unbends completely) Soft aluminum on the other hand has a very large soread between yield and ultimate. It would not take much load until the piece starts to take a permanent set, but you can add quite a bit more load before it breaks. On top of that materials act differently in compression, tension and shear. What this means is that your well designed aircraft can safely go maneuver, fly into gusts, or whatever, staying below 3.8 g's, and you can keep doing it. However, when you start doing outside snaps in your Piet and exceed the magic 3.8, -1.52, but stay within the 1.5 safety factor, then some components may permanently deform, but nothing should break. You'll get back safely on the ground, but it may be the last flight for that airplane. Of course the Pietenpol was not designed this way. Back then they use empirical data for many light aircraft designs. Look at something similarly sized and with similar performance and and make your parts the same way. Sure, calculate some basic beam bending loads on the spars and other major parts, and call it good. This resulted in some overbuilt airplanes. For instance look at our ribs compared to some others; 1/4" x 1/4" rib trusses. They really look flimsy after building my Piet ribs. My philosophy for Piet building is therefore: If it's been built that way before, safely, and on several aircraft, then it's OK. If I decide to do it differently (size of lift struts, material substitutions, etc.) then I'll make at least some basic load calculations. There are several old articles in Sport Aviation (search the EAA's online archives for 'structural analysis'). One in particular (mid 60's maybe?) specifically addresses loads in a high wing strut braced monoplane. They show examples in a tabular 'spreadsheet' format (long before spread sheets were invented) that could be implemented pretty easily. --Ken On Mon, 19 Oct 2009 21:32:39 -0700, "tkreiner" wrote: > > Guys, > > As a Consulting Mechanical Engineer, I'm going to jump in here, and make a > few observations, as not all of us have the same background. > > When a stressed member is being discussed, it might be helpful to add the > equations needed so anyone can use them in the future. In the case of the > struts being discussed, we have several concepts which, although understood > by engineers and those really familiar with the issue being discussed, can > become confusing and/or confused. > > First, the Yield Strength of 4130 is somewhat less than the 95,000 psi > given. It turns out that 95,000 psi is generally given as the Ultimate > Strength of 4130. The Yield Strength, however, defined to be that level of > stress at which permanent deformation (stretching) takes place, is around > 75,000 psi. (When doing stress calculations, most engineers will use the > Yield Strength, not the Ultimate, or breaking strength. We not only don't > want the member to permanently stretch, we damn sure don't want it to > break. ) > > The equation describing the strength of any member in tension, and a > limited amount of cases in compression, is: > > s = P/A, where s is the Yield Strength, P is the load in pounds, and > A is the cross-sectional area of the member. > > In the case of the strut in the discussion, we are looking for the load the > member will carry, so we rearrange the equation, then "plug & chug" to get: > > P = s x A = 75,000 x .149 = 11,175 pounds. > > This will work very nicely in the case of a member being loaded in tension. > If that member is a slender bar, shaft, tube, etc., however, column > buckling equations come into play. > > If the member is a strut at an angle.... we must first apply a little Trig > to determine the vector load on the member prior to determining the load > carrying capacity of that member. > > Hope this helps. > > -------- > Tom Kreiner > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=268647#268647 > > > > > > > > ________________________________ Message 16 ____________________________________ Time: 12:20:32 PM PST US Subject: Pietenpol-List: Re: strut stress From: "ivan.todorovic" CDAWSON5854(at)shaw.ca wrote: > ... > I finaly scanned them for you guys strutting about. > ... It was hardly readable for me, so I've run it through my OCR software, here is the result: --- Stress Analysis Made Painless by Raoul J. Hoffman Aeronautical Designing Engineer Airplane members, subjected to axial compression loads, are called posts, columns or struts. No formula has yet been found which will give you the exact load permissible under various conditions. There are two formulas commonly used for strut calculations -- one for short struts and one for long members. Usually, Johnson's parabolic formula is used for short struts and Euler's formula for long struts. These formulae are based on the assumptions that the strut is straight, of homogenous material and that the load is applied at the center of gravity of the strut. The formulae shown on the chart are simplified for ready use. (P) denotes the load permissible in pounds and (A) the cross-sectional area in square inches. Therefore, P/A will give you the average stress per square inch. (L) denotes the free length, (r) the radius of gyration. (L/r) the slenderness ratio and (E) the modulus of elasticity. The modulus of elasticity is a constant factor of elongation. taken within the elastic limit and may be expressed as the theoretical load required to elongate a rod to twice the original length, having a cross-sectional area of one square inch. The elastic limit is the limit of stress within which the deformation or elongation disappears after removing the stress. The area of cross-section is easily found by measuring. We calibrated a special scale for the weight of a one foot length of steel tubing to use instead of tire area. (L), the free length. is the unsupported length or the bar between the points of inflection, or the points where the curvature of the flexed strut reverses. The free Length of a strut, with pin ends or rounded ends, is equal to the total length of the strut. For a strut with fixed ends (restrained), the free length would be 50 percent of its actual length, but in airplane work we should seldom be below 70 percent. The radius of gyration is a factor depending on the outline and area or the strut cross-section. These multiplication constants are noted on the chart for a few standard strut sections. Multiply the outside dimension by the constant and you will have the radius of gyration. always take the smaller for (r) dimension, specially in case of a rectangular section, except when you are sure the strut is braced or notable to deflect in the perpendicular direction. The slenderness ratio (L/r) is the ratio of the free length of the strut to the radius of gyration. The selection of the formula depends on the slenderness ratio, which will also determine the average stress per square inch. Both formulae are valid as long as the ratio of the outside dimension to the wall thickness does not go beyond a certain value. Estimating an engine-mount vie use the total length for the free length, even if the ends are restrained at the connections. For fuselage members, we use 70 percent to 100 percent for the free length, depending on the judgment of the designer. Do not go beyond a slenderness ratio of 150 for carbon steel nor beyond 180 for chrome molybdenum steel which may be subjected to an external load, and not over 200 in case the member is protected from external load. The minimum wall thickness for steel tubing should not be less than .035 in., except for the rear end of a cabin or for fuselage members other than longerons where .028 in. tubing can be used. A margin of safety of 50 percent must be maintained throughout. Scale No 1 on our chart shows the slenderness ratio for spruce on the lower part and for mild carbon and chrome molybdenum on the upper part, with the corresponding maximum loads per square inch on scale No. 4. The calibrations for both steels over 130 are the same, involving an error of 3 percent, the percentage difference between their respective modulus of elasticity. By following the example you are able to design your own strut by changing the cross-sectional area of the strut until it can carry the load required. --- Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268707#268707 ________________________________ Message 17 ____________________________________ Time: 12:35:34 PM PST US Subject: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol From: "Catdesigns" Go to http://www.westcoastpiet.com/construction.htm The second link down,"Simplified Wing Stress Analysis.pdf "is probably the article Ken is thinking about. It's a 10 meg PDF so be warned. Chris -------- Chris Tracy Sacramento, CA WestCoastPiet.com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268709#268709 ________________________________ Message 18 ____________________________________ Time: 12:59:08 PM PST US Subject: Pietenpol-List: Tail feather drain holes From: "at7000ft" Question for anyone who has finished covering. How many drain grommets did you put on your tail feather panels and where did you put them? Thanks Rick, busy rib lacing. -------- Rick Holland Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268710#268710 ________________________________ Message 19 ____________________________________ Time: 01:38:56 PM PST US From: "Jack Phillips" Subject: RE: Pietenpol-List: Prop choices for A-65 I've got a Sensenich 72-42 and am not all that happy with it. I have a St Croix 76-36 that I have never tried but will some day. Jack Phillips NX899JP Raleigh, NC _____ From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Skip Gadd Sent: Tuesday, October 20, 2009 10:09 AM Subject: RE: Pietenpol-List: Prop choices for A-65 Ryan, Have had 2 props on Felix the GN-1, A-65, plane weighs 720 lbs. 1. McCauley Met-L-Prop 74-43. Climbs good can handle pac up to 220 if is not too hot. Cruse at 2150 68 to 70 MPH. Max RPM 2375. 2. Hegy I got from Don E. 72-44 Climbs not as good can handle pac up to 180. Curse at 1950 72 MPH. Max RPM 2150. Interestingly, the plane seems to get 3.8 GPH with ether prop. I would like to have a Sensenich 72-42. Skip ----- Original Message ----- From: Ryan Mueller Sent: 10/20/2009 7:59:17 AM Subject: Pietenpol-List: Prop choices for A-65 Good morning all, There will be an A-65-8 making it's way to our shop in a couple of weeks. I am contemplating it's future. It is complete, and should be a runner; however it does not come with a prop. I would prefer to have a wood prop on the Piet. Can those of you that have wood props flying on A-65's on your Pietenpol's comment on the make, size, and pitch that you are running, or you experiences in the past with varying configurations? Thanks much, and have a good morning. Ryan <> ________________________________ Message 20 ____________________________________ Time: 01:46:13 PM PST US Subject: Pietenpol-List: Re: strut stress From: "K5YAC" Uhhh... -------- Mark - working on wings Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268715#268715 Attachments: http://forums.matronics.com//files/say_what_168.jpg ________________________________ Message 21 ____________________________________ Time: 01:53:45 PM PST US Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol From: Ken Howe Yes Chris, that's the one I was thinking of. You've got a lot of got stuff referenced there. On Tue, 20 Oct 2009 12:35:20 -0700, "Catdesigns" wrote: > > Go to http://www.westcoastpiet.com/construction.htm > > > The second link down,"Simplified Wing Stress Analysis.pdf "is probably the > article Ken is thinking about. It's a 10 meg PDF so be warned. > > Chris > > -------- > Chris Tracy > Sacramento, CA > WestCoastPiet.com > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=268709#268709 > > > > > > > > ________________________________ Message 22 ____________________________________ Time: 01:54:55 PM PST US Subject: Re: Pietenpol-List: Prop choices for A-65 From: Ryan Mueller Dan Y. mentioned to me that a number of people (Jeff Boatright, Gene, etc) are using Jay Anderson (Cloudcars) scimitar props, and they seem to enjoy the performance. The scimitar props do have a nice 'antiquey' look to them. I think 76x38 was the size they have used. Anyone with a Jay Anderson prop care to comment? Any ground clearance issues with the longer blades? What about the Sensenich are you not happy with, Jack? Ryan On Tue, Oct 20, 2009 at 3:11 PM, Jack Phillips wrot e: > I=92ve got a Sensenich 72-42 and am not all that happy with it. I have a > St Croix 76-36 that I have never tried but will some day. > > > Jack Phillips > > NX899JP > > Raleigh, NC > > > ------------------------------ > > *From:* owner-pietenpol-list-server@matronics.com [mailto: > owner-pietenpol-list-server@matronics.com] *On Behalf Of *Skip Gadd > *Sent:* Tuesday, October 20, 2009 10:09 AM > > *To:* pietenpol-list@matronics.com > *Subject:* RE: Pietenpol-List: Prop choices for A-65 > > > Ryan, > > Have had 2 props on Felix the GN-1, A-65, plane weighs 720 lbs. > > 1. McCauley Met-L-Prop 74-43. Climbs good can handle pac up to 220 if is > not too hot. Cruse at 2150 68 to 70 MPH. Max RPM 2375. > > 2. Hegy I got from Don E. 72-44 Climbs not as good can handle pac up to > 180. Curse at 1950 72 MPH. Max RPM 2150. > > Interestingly, the plane seems to get 3.8 GPH with ether prop. > > I would like to have a Sensenich 72-42. > > Skip > > > ----- Original Message ----- > > *From:* Ryan Mueller > > *To: *pietenpol-list@matronics.com > > *Sent:* 10/20/2009 7:59:17 AM > > *Subject:* Pietenpol-List: Prop choices for A-65 > > > Good morning all, > > > There will be an A-65-8 making it's way to our shop in a couple of weeks. I > am contemplating it's future. It is complete, and should be a runner; > however it does not come with a prop. I would prefer to have a wood prop on > the Piet. Can those of you that have wood props flying on A-65's on your > Pietenpol's comment on the make, size, and pitch that you are running, or > you experiences in the past with varying configurations? Thanks much, and > have a good morning. > > > Ryan > > *<>* > > * * > > * * > > ** > > ** > > ** > > *http://www.matronics.com/Navigator?Pietenpol-List* > > ** > > ** > > *http://forums.matronics.com* > > ** > > ** > > *http://www.matronics.com/contribution* > > * * > > * > =========== w.matronics.com/Navigator?Pietenpol-List =========== =========== com/contribution =========== > * > > ________________________________ Message 23 ____________________________________ Time: 02:04:19 PM PST US From: Matt Keyes Subject: Pietenpol-List: Skis I have a set of skis very similar to the picture from the West Coast Piet s ite for my Quicksilver MXII, with one addition, small wheels for taxiing on the pavement.- The wheels are off a snowmobile, I think, (I did not make the skis, think aluminum pulleys with a solid rubber guide).- The skis a re set up just like the photo that was posted, except uses heavy plastic fo r the runner instead of wood, with a metal skid plate for reenforcement.- The wheels protrude through the center about 1/2 inch-via-a small cut o ut.-They work quite welll in soft snow as long as it isn't too deep, but the wheels do dig in a bit and I'm careful about not landing on crusty snow , for fear of breaking through.-They slip over the axle the same as in th e photo from the West Coast Piet site.-I don't think I have a picture tha t shows the wheels, but I can post one if anyone is interested.- - Matt Keyes Richland Center, WI=0A=0A=0A ________________________________ Message 24 ____________________________________ Time: 02:28:11 PM PST US From: "Mike Whaley" Subject: Re: [piet] RE: Pietenpol-List: Chapter 1218 Pietenpol? That's the first time I think I've ever seen EAAers describe successfully completing an aircraft project in a few months as a "total failure"... what the heck... Mike Whaley MerlinFAC@cfl.rr.com ----- Original Message ----- From: "Bill Church" Sent: Monday, October 19, 2009 10:51 PM Subject: [piet] RE: Pietenpol-List: Chapter 1218 Pietenpol? I'm with you, dan. That tail... UGH! Looks like they decided to make the tail out of steel tube, but something went awry. YUK. Some things shouldn't be messed with. Personally, I don't like the look of the vertical fin faired into the fuselage on a Pietenpol. But that's just my opinion. Well, I'm probably not the only one who thinks that (I hope). Bill C. -----Original Message----- From: owner-pietenpol-list-server@matronics.com on behalf of helspersew@aol.com Sent: Mon 19/10/2009 7:44 PM Subject: Re: Pietenpol-List: Chapter 1218 Pietenpol? Dan, I am sitting here scratching my head looking at those pictures. Nothing I see looks like a Pietenpol to me. Am I crazy? This is NOT a Pietenpol. Dan Helsper Poplar Grove, IL. ________________________________ Message 25 ____________________________________ Time: 02:28:40 PM PST US Subject: RE: Pietenpol-List: Re: strut stress From: "Bill Church" The text in the body of the article was not a problem to read - it's the little stuff in the chart that's a challenge . Bet your OCR software can't figure that stuff out. -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of ivan.todorovic Sent: Tuesday, October 20, 2009 3:20 PM Subject: Pietenpol-List: Re: strut stress --> CDAWSON5854(at)shaw.ca wrote: > ... > I finaly scanned them for you guys strutting about. > ... It was hardly readable for me, so I've run it through my OCR software, here is the result: --- Stress Analysis Made Painless by Raoul J. Hoffman Aeronautical Designing Engineer Airplane members... ________________________________ Message 26 ____________________________________ Time: 02:40:44 PM PST US From: "Mike Tunnicliffe" Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Hi John, there is no simple equation to tell you the various loads that a strut will see under all flight and landing conditions. However you can get close if you make several assumptions, such as the chord wise load distribution at maximum lift which will determine the difference in loads that the front and rear struts will see. Also the span wise load distribution at maximum lift which will determine the ratio of the load shared between the main struts and the cabane struts. If you have used longer cabane struts and some dihedral the angle of the main struts will be different as will the tension and compression loads they see. Using a different airfoil will change the chordwise load distribution. Building the wing a bay longer will change the loads the lift struts see. The weight and balance of aircraft has an influence. As you can see the calculations need to be done for each particular aircraft. This is not an attempt to discourage you, as I intend to use round tube for my struts as streamline tube is difficult and expensive to get where I live, however the math for my aircraft may not suit yours. Regards Mike T. ----- Original Message ----- From: AMsafetyC@aol.com To: pietenpol-list@matronics.com Sent: Wednesday, October 21, 2009 2:40 AM Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol For me, not being math savvy, are considered complex concepts and calculations that are well beyond my simple math skills and aerodynamic calculation capabilities. I would like someone to provide a simple but effective way for me and other mathematically challenged builders to determine the efficacy of our material choices and their ability to respond to a range of loads without failure? John ________________________________ Message 27 ____________________________________ Time: 02:42:16 PM PST US Subject: RE: Pietenpol-List: Re: strut stress From: Ken Howe I've got that book stashed away somewhere at home. I'll dig it out and see if my copy is any more readable as a scan or photo. --Ken On Tue, 20 Oct 2009 17:28:14 -0400, "Bill Church" wrote: > > > > The text in the body of the article was not a problem to read - it's the > little stuff in the chart that's a challenge . > Bet your OCR software can't figure that stuff out. > > -----Original Message----- > From: owner-pietenpol-list-server@matronics.com > [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of > ivan.todorovic > Sent: Tuesday, October 20, 2009 3:20 PM > To: pietenpol-list@matronics.com > Subject: Pietenpol-List: Re: strut stress > > --> > > > CDAWSON5854(at)shaw.ca wrote: >> ... >> I finaly scanned them for you guys strutting about. >> ... > > > It was hardly readable for me, so I've run it through my OCR software, > here is the result: > > --- > Stress Analysis Made Painless > > by Raoul J. Hoffman > Aeronautical Designing Engineer > > Airplane members... > > > ________________________________ Message 28 ____________________________________ Time: 02:44:43 PM PST US Subject: Pietenpol-List: Re: strut stress From: "ivan.todorovic" eng(at)canadianrogers.com wrote: > Bet your OCR software can't figure that stuff out. You won a cigar. do not archive. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268726#268726 ________________________________ Message 29 ____________________________________ Time: 02:50:11 PM PST US From: "Gene Rambo" Subject: Re: Pietenpol-List: Prop choices for A-65 I do not know if you are referring to me when you said "Gene", but while I do have a Jay Anderson prop, I have not run it yet. My prop is somewhat different from most he made as he wanted to experiment and make mine a little thicker in chord and longer than most. Jay thinks that the Model A will produce more torque than is being asked of them with most props and wanted to try something, mostly because he had a blank that was longer than usual. We'll see, one day, and he offered to change it back to the more traditional profile if it does not perform well. Gene Rambo do not archive ----- Original Message ----- From: Ryan Mueller To: pietenpol-list@matronics.com Sent: Tuesday, October 20, 2009 4:51 PM Subject: Re: Pietenpol-List: Prop choices for A-65 Dan Y. mentioned to me that a number of people (Jeff Boatright, Gene, etc) are using Jay Anderson (Cloudcars) scimitar props, and they seem to enjoy the performance. The scimitar props do have a nice 'antiquey' look to them. I think 76x38 was the size they have used. Anyone with a Jay Anderson prop care to comment? Any ground clearance issues with the longer blades? What about the Sensenich are you not happy with, Jack? Ryan On Tue, Oct 20, 2009 at 3:11 PM, Jack Phillips > wrote: I=92ve got a Sensenich 72-42 and am not all that happy with it. I have a St Croix 76-36 that I have never tried but will some day. Jack Phillips NX899JP Raleigh, NC ------------------------------------------------------------------------- --- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Skip Gadd Sent: Tuesday, October 20, 2009 10:09 AM To: pietenpol-list@matronics.com Subject: RE: Pietenpol-List: Prop choices for A-65 Ryan, Have had 2 props on Felix the GN-1, A-65, plane weighs 720 lbs. 1. McCauley Met-L-Prop 74-43. Climbs good can handle pac up to 220 if is not too hot. Cruse at 2150 68 to 70 MPH. Max RPM 2375. 2. Hegy I got from Don E. 72-44 Climbs not as good can handle pac up to 180. Curse at 1950 72 MPH. Max RPM 2150. Interestingly, the plane seems to get 3.8 GPH with ether prop. I would like to have a Sensenich 72-42. Skip ----- Original Message ----- From: Ryan Mueller To: pietenpol-list@matronics.com Sent: 10/20/2009 7:59:17 AM Subject: Pietenpol-List: Prop choices for A-65 Good morning all, There will be an A-65-8 making it's way to our shop in a couple of weeks. I am contemplating it's future. It is complete, and should be a runner; however it does not come with a prop. I would prefer to have a wood prop on the Piet. Can those of you that have wood props flying on A-65's on your Pietenpol's comment on the make, size, and pitch that you are running, or you experiences in the past with varying configurations? Thanks much, and have a good morning. Ryan <> http://www.matronics.com/Navigator?Pietenpol-Listhttp://forums.matronics.comhttp://www.matronics.com/contribution " target="_blank">http://www.matronics.com/Navigator?Pietenpol-List a>http://forums.matronics.com _blank">http://www.matronics.com/contribution http://www.matronics.com/Navigator?Pietenpol-List http://www.matronics.com/contribution ________________________________ Message 30 ____________________________________ Time: 03:03:59 PM PST US Subject: Re: Pietenpol-List: Prop choices for A-65 From: Ryan Mueller Sorry Gene R...I think it was 'Gene and Tammy in Tennesee' Gene. Should hav e specified... Ryan do not archive On Tue, Oct 20, 2009 at 4:49 PM, Gene Rambo wrote: > I do not know if you are referring to me when you said "Gene", but while > I do have a Jay Anderson prop, I have not run it yet. My prop is somewha t > different from most he made as he wanted to experiment and make mine a > little thicker in chord and longer than most. Jay thinks that the Model A > will produce more torque than is being asked of them with most props and > wanted to try something, mostly because he had a blank that was longer th an > usual. We'll see, one day, and he offered to change it back to the more > traditional profile if it does not perform well. > > Gene Rambo > > do not archive > > ----- Original Message ----- > *From:* Ryan Mueller > *To:* pietenpol-list@matronics.com > *Sent:* Tuesday, October 20, 2009 4:51 PM > *Subject:* Re: Pietenpol-List: Prop choices for A-65 > > Dan Y. mentioned to me that a number of people (Jeff Boatright, Gene, etc ) > are using Jay Anderson (Cloudcars) scimitar props, and they seem to enjoy > the performance. The scimitar props do have a nice 'antiquey' look to the m. > I think 76x38 was the size they have used. Anyone with a Jay Anderson pro p > care to comment? Any ground clearance issues with the longer blades? > What about the Sensenich are you not happy with, Jack? > > Ryan > > On Tue, Oct 20, 2009 at 3:11 PM, Jack Phillips wr ote: > >> I=92ve got a Sensenich 72-42 and am not all that happy with it. I have a >> St Croix 76-36 that I have never tried but will some day. >> >> >> >> Jack Phillips >> >> NX899JP >> >> Raleigh, NC >> >> >> ------------------------------ >> >> *From:* owner-pietenpol-list-server@matronics.com [mailto: >> owner-pietenpol-list-server@matronics.com] *On Behalf Of *Skip Gadd >> *Sent:* Tuesday, October 20, 2009 10:09 AM >> >> *To:* pietenpol-list@matronics.com >> *Subject:* RE: Pietenpol-List: Prop choices for A-65 >> >> >> >> Ryan, >> >> Have had 2 props on Felix the GN-1, A-65, plane weighs 720 lbs. >> >> 1. McCauley Met-L-Prop 74-43. Climbs good can handle pac up to 220 if is >> not too hot. Cruse at 2150 68 to 70 MPH. Max RPM 2375. >> >> 2. Hegy I got from Don E. 72-44 Climbs not as good can handle pac up to >> 180. Curse at 1950 72 MPH. Max RPM 2150. >> >> Interestingly, the plane seems to get 3.8 GPH with ether prop. >> >> I would like to have a Sensenich 72-42. >> >> Skip >> >> >> >> >> >> ----- Original Message ----- >> >> *From:* Ryan Mueller >> >> *To: *pietenpol-list@matronics.com >> >> *Sent:* 10/20/2009 7:59:17 AM >> >> *Subject:* Pietenpol-List: Prop choices for A-65 >> >> >> >> Good morning all, >> >> >> >> There will be an A-65-8 making it's way to our shop in a couple of weeks .. >> I am contemplating it's future. It is complete, and should be a runner; >> however it does not come with a prop. I would prefer to have a wood prop on >> the Piet. Can those of you that have wood props flying on A-65's on your >> Pietenpol's comment on the make, size, and pitch that you are running, o r >> you experiences in the past with varying configurations? Thanks much, an d >> have a good morning. >> >> >> >> Ryan >> >> *<>* >> >> * * >> >> * * >> >> ** >> >> ** >> >> ** >> >> *http://www.matronics.com/Navigator?Pietenpol-List* >> >> ** >> >> ** >> >> *http://forums.matronics.com* >> >> ** >> >> ** >> >> *http://www.matronics.com/contribution* >> >> * * >> >> * >> >> " target="_blank"> http://www.matronics.com/Navigator?Pietenpol-List >> a> http://forums.matronics.com >> _blank"> http://www.matronics.com /contribution >> * >> >> > * > > title=http://www.matronics.com/Navigator?Pietenpol-List href="http:// www.matronics.com/Navigator?Pietenpol-List">http://www.matronics.com/Naviga tor?Pietenpol-List > href="http://forums.matronics.com">http://forums.matronics.com > href="http://www.matronics.com/contribution">http://www.matronics.com/c > * > > * > =========== w.matronics.com/Navigator?Pietenpol-List =========== =========== com/contribution =========== > > * > > ________________________________ Message 31 ____________________________________ Time: 03:27:29 PM PST US From: "David Paule" Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Not only each aircraft if they aren't built to the plans, but each of the several loading conditions - Stall at maneuvering speed, Gust at max cruise, Max gs at Vne, And these again for negative loads. Certainly the chordwise loads change for each of these. The spanwise loads might, too. No one said it was easy! David Paule ----- Original Message ----- From: Mike Tunnicliffe To: pietenpol-list@matronics.com Sent: Tuesday, October 20, 2009 3:40 PM Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol Hi John, there is no simple equation to tell you the various loads that a strut will see under all flight and landing conditions. However you can get close if you make several assumptions, such as the chord wise load distribution at maximum lift which will determine the difference in loads that the front and rear struts will see. Also the span wise load distribution at maximum lift which will determine the ratio of the load shared between the main struts and the cabane struts. If you have used longer cabane struts and some dihedral the angle of the main struts will be different as will the tension and compression loads they see. Using a different airfoil will change the chordwise load distribution. Building the wing a bay longer will change the loads the lift struts see. The weight and balance of aircraft has an influence. As you can see the calculations need to be done for each particular aircraft. This is not an attempt to discourage you, as I intend to use round tube for my struts as streamline tube is difficult and expensive to get where I live, however the math for my aircraft may not suit yours. Regards Mike T. ----- Original Message ----- From: AMsafetyC@aol.com To: pietenpol-list@matronics.com Sent: Wednesday, October 21, 2009 2:40 AM Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol For me, not being math savvy, are considered complex concepts and calculations that are well beyond my simple math skills and aerodynamic calculation capabilities. I would like someone to provide a simple but effective way for me and other mathematically challenged builders to determine the efficacy of our material choices and their ability to respond to a range of loads without failure? John ________________________________ Message 32 ____________________________________ Time: 05:04:01 PM PST US From: "Gene & Tammy" Subject: Pietenpol-List: Props for A 65 Ryan, here is a photo of my 76 X 38 Jay Anderson Scimitar prop. Before it, I used a Sterba 74 X 38 which was good, but I like the Scimitar a lot better. It "bites" very well for climb and then seems to flatens out for cruise at 2150. Clears the ground with no problem. We held a Aviation Day here at OM4 on the 10th of this month and had a large number of WW II war birds plus the EAA B17, Aluminum Overcast, show up. I put my Ol' Piet out on the ramp, just in case someone wanted to see a real airplane. The B17 and the Piet stole the show! Crowd loved them both. Lots of comments on both the piet and the prop. The crew of the B17 invited me to take a flight with them and I must say it was a thrill. I sat in the jump seat behind the pilot. I offered to let him fly my Piet if he would let me fly the 17. He didn't answer. Gene in Beautiful sunny Tennessee. (For the first time in several weeks I'll have a day off tomorrow and the sun is suppose to shine. I'll spend most of it flying N502R and the rest of it riding the Gold Wing.) ________________________________ Message 33 ____________________________________ Time: 05:24:29 PM PST US Subject: Pietenpol-List: Prop choices for A-65 From: helspersew@aol.com Hello all you good people, When I tested my self-carved prop on my model A, I measured (with an over- sized fish scale) the thrust to be 265 lbs. at full throttle. I would be curious to know what others have measured, with A-65's or Corvairs or wha tever. I understand that this is probably an unconventional way to measure performance, but it makes a whole "lot o" sense to me, especially before the first flight. http://s564.photobucket.com/albums/ss83/dhelsper/?actio n=view¤t=1ststart-upmodelAwithcarvedprop.flv Dan Helsper Poplar Grove, IL. ________________________________ Message 34 ____________________________________ Time: 05:31:02 PM PST US From: Tim Willis Subject: Re: Pietenpol-List: Props for A 65 Gene, Your plane is a knockout, and the prop really helps the effect. I can believe that you and the B-17 were the stars. A couple of unrelated questions: -- Which color white and green on your paint, is the green "Cubby Trainer Green"? -- Do we see heat muffs on each side for rear exhausts, and if so, how plumbed, one for carb, one for cockpit heat? Are your stacks stainless, and where sourced? (I like your lack of merging exhausts, keeping good flow, and avoiding custom complexity.) (I am planning white for my wing and much metal work [have that white 2-part epoxy], and still considering many different bright and/or darker colors for contrast.) Tim in central TX (still missing TN) -----Original Message----- From: Gene & Tammy Sent: Oct 20, 2009 7:01 PM Subject: Pietenpol-List: Props for A 65 Ryan, here is a photo of my 76 X 38 Jay Anderson Scimitar prop. Before it, I used a Sterba 74 X 38 which was good, but I like the Scimitar a lot better. It "bites" very well for climb and then seems to flatens out for cruise at 2150. Clears the ground with no problem. We held a Aviation Day here at OM4 on the 10th of this month and had a large number of WW II war birds plus the EAA B17, Aluminum Overcast, show up. I put my Ol' Piet out on the ramp, just in case someone wanted to see a real airplane. The B17 and the Piet stole the show! Crowd loved them both. Lots of comments on both the piet and the prop. The crew of the B17 invited me to take a flight with them and I must say it was a thrill. I sat in the jump seat behind the pilot. I offered to let him fly my Piet if he would let me fly the 17. He didn't answer. Gene in Beautiful sunny Tennessee. (For the first time in several weeks I'll have a day off tomorrow and the sun is suppose to shine. I'll spend most of it flying N502R and the rest of it riding the Gold Wing.) ________________________________ Message 35 ____________________________________ Time: 05:42:29 PM PST US From: "Gary Boothe" Subject: RE: Pietenpol-List: Props for A 65 Great story, Gene. I'm sure that pilot was intimidated by that open cockpit flying machine! Gary Boothe Cool, Ca. Pietenpol WW Corvair Conversion, mounted Tail done, Fuselage on gear (15 ribs down.) Do not archive _____ From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Gene & Tammy Sent: Tuesday, October 20, 2009 5:02 PM Subject: Pietenpol-List: Props for A 65 Ryan, here is a photo of my 76 X 38 Jay Anderson Scimitar prop. Before it, I used a Sterba 74 X 38 which was good, but I like the Scimitar a lot better. It "bites" very well for climb and then seems to flatens out for cruise at 2150. Clears the ground with no problem. We held a Aviation Day here at OM4 on the 10th of this month and had a large number of WW II war birds plus the EAA B17, Aluminum Overcast, show up. I put my Ol' Piet out on the ramp, just in case someone wanted to see a real airplane. The B17 and the Piet stole the show! Crowd loved them both. Lots of comments on both the piet and the prop. The crew of the B17 invited me to take a flight with them and I must say it was a thrill. I sat in the jump seat behind the pilot. I offered to let him fly my Piet if he would let me fly the 17. He didn't answer. Gene in Beautiful sunny Tennessee. (For the first time in several weeks I'll have a day off tomorrow and the sun is suppose to shine. I'll spend most of it flying N502R and the rest of it riding the Gold Wing.) ________________________________ Message 36 ____________________________________ Time: 05:52:38 PM PST US From: "Gary Boothe" Subject: RE: Pietenpol-List: Prop choices for A-65 Dan, Still love that video!! And, Yes, I think your thrust test has merit, at least to a country boy. Gary Boothe Cool, Ca. Pietenpol WW Corvair Conversion, mounted Tail done, Fuselage on gear (15 ribs down.) Do not archive _____ From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of helspersew@aol.com Sent: Tuesday, October 20, 2009 5:23 PM Subject: Pietenpol-List: Prop choices for A-65 Hello all you good people, When I tested my self-carved prop on my model A, I measured (with an over-sized fish scale) the thrust to be 265 lbs. at full throttle. I would be curious to know what others have measured, with A-65's or Corvairs or whatever. I understand that this is probably an unconventional way to measure performance, but it makes a whole "lot o" sense to me, especially before the first flight. http://s564.photobucket.com/albums/ss83/dhelsper/?action=view ¤t=1ststart-upmodelAwithcarvedprop.flv Dan Helsper Poplar Grove, IL. ________________________________ Message 37 ____________________________________ Time: 06:45:15 PM PST US Subject: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol From: "Bill Church" John (PM Danger), Here I was, thinking that you wanted to know a simple method to determine whether a certain size of round 4130 tubing could be substituted for the 1934 special streamline tubing shown in the plans, and I was thinking about how there is NO SIMPLE ANSWER or formula to give, and then you tell us you're talking about wooden struts. There are so many variables (without even getting int the specifics of your unique plane)! There's the species of wood, the "quality" of the particular pieces of wood used, the size and shape of the struts, the thickness and number of laminations, the glue used, not to mention the "metal inserts". You mention that you are not an engineer. Well, as you know, I am an engineer, but I'm not an aeronautical engineer. Despite my background, I do not feel qualified to determine the suitability of wooden flying struts for my Piet, let alone someone else's. I think your best option would be to track down a builder that has successfully built and flown (for a significant amount of time) a wooden-strutted Piet, and borrow that design (if they are willing to share it with you). It sounds like you have built a set of struts based on "that looks about right". The flying struts are WAY too important to be approached in that manner. Like you say, a catastrophic failure in flight would really screw up your day. Be very careful with this stuff. As much as I like the look of wooden struts I will be using steel struts on my plane. Bill C. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=268755#268755 ________________________________ Message 38 ____________________________________ Time: 06:46:17 PM PST US From: "Skip Gadd" Subject: RE: Pietenpol-List: Prop choices for A-65 Jack, What numbers do you get with the Sensenich? The reason I have been wanting one is because they do pretty good on Cubs, and they are nice and fat and user friendly for hand propping. Skip ----- Original Message ----- From: Jack Phillips Sent: 10/20/2009 4:42:50 PM Subject: RE: Pietenpol-List: Prop choices for A-65 Ive got a Sensenich 72-42 and am not all that happy with it. I have a St Croix 76-36 that I have never tried but will some day. Jack Phillips NX899JP Raleigh, NC From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Skip Gadd Sent: Tuesday, October 20, 2009 10:09 AM Subject: RE: Pietenpol-List: Prop choices for A-65 Ryan, Have had 2 props on Felix the GN-1, A-65, plane weighs 720 lbs. 1. McCauley Met-L-Prop 74-43. Climbs good can handle pac up to 220 if is not too hot. Cruse at 2150 68 to 70 MPH. Max RPM 2375. 2. Hegy I got from Don E. 72-44 Climbs not as good can handle pac up to 180. Curse at 1950 72 MPH. Max RPM 2150. Interestingly, the plane seems to get 3.8 GPH with ether prop. I would like to have a Sensenich 72-42. Skip ----- Original Message ----- From: Ryan Mueller Sent: 10/20/2009 7:59:17 AM Subject: Pietenpol-List: Prop choices for A-65 Good morning all, There will be an A-65-8 making it's way to our shop in a couple of weeks. I am contemplating it's future. It is complete, and should be a runner; however it does not come with a prop. I would prefer to have a wood prop on the Piet. Can those of you that have wood props flying on A-65's on your Pietenpol's comment on the make, size, and pitch that you are running, or you experiences in the past with varying configurations? Thanks much, and have a good morning. Ryan <> http://www.matronics.com/Navigator?Pietenpol-List http://forums.matronics.com http://www.matronics.com/contribution ________________________________ Message 39 ____________________________________ Time: 07:24:38 PM PST US From: Tim Willis Subject: Re: Pietenpol-List: Prop choices for A-65 Dan, I love the video, esp. as you do a little victory dance. I would, too. I think your personally carved prop is just amazing. Great plane. We have seen your cowl shots, too. You are getting so close to being done. Tim in central TX -----Original Message----- From: helspersew@aol.com Sent: Oct 20, 2009 7:22 PM Subject: Pietenpol-List: Prop choices for A-65 Hello all you good people, When I tested my self-carved prop on my model A, I measured (with an over-sized fish scale) the thrust to be 265 lbs. at full throttle. I would be curious to know what others have measured, with A-65's or Corvairs or whatever. I understand that this is probably an unconventional way to measure performance, but it makes a whole "lot o" sense to me, especially before the first flight. http://s564.photobucket.com/albums/ss83/dhelsper/?action=view¤t=1ststart-upmodelAwithcarvedprop.flv Dan Helsper Poplar Grove, IL. ________________________________ Message 40 ____________________________________ Time: 07:28:27 PM PST US Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol From: Robert Ray I remember some one did this and there was a picture of the plane in the experimenter. I'll see if I can find the issue and get your address I will mail the picture to you if I can find it. Russell On Tue, Oct 20, 2009 at 9:44 PM, Bill Church wrote: > billspiet@sympatico.ca> > > John (PM Danger), > Here I was, thinking that you wanted to know a simple method to determine > whether a certain size of round 4130 tubing could be substituted for the > 1934 special streamline tubing shown in the plans, and I was thinking about > how there is NO SIMPLE ANSWER or formula to give, and then you tell us > you're talking about wooden struts. There are so many variables (without > even getting int the specifics of your unique plane)! There's the species of > wood, the "quality" of the particular pieces of wood used, the size and > shape of the struts, the thickness and number of laminations, the glue used, > not to mention the "metal inserts". > You mention that you are not an engineer. Well, as you know, I am an > engineer, but I'm not an aeronautical engineer. Despite my background, I do > not feel qualified to determine the suitability of wooden flying struts for > my Piet, let alone someone else's. I think your best option would be to > track down a builder that has successfully built and flown (for a > significant amount of time) a wooden-strutted Piet, and borrow that design > (if they are willing to share it with you). > It sounds like you have built a set of struts based on "that looks about > right". The flying struts are WAY too important to be approached in that > manner. Like you say, a catastrophic failure in flight would really screw up > your day. Be very careful with this stuff. > As much as I like the look of wooden struts I will be using steel struts on > my plane. > > Bill C. > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=268755#268755 > > ________________________________ Message 41 ____________________________________ Time: 07:43:08 PM PST US From: "Clif Dawson" Subject: Re: Pietenpol-List: Re: strut stress I'm running windows XP but what I'm saying here should have an equivalent in other systems. The article was scanned as a jpeg and sent to my picture file. In there I can double click any image and it comes up in it's own window. This image can then be enlarged up to 400%. So enlarging the chart till it's comfortable makes it quite readable. For me that's 150-200%. Beyond that it begins to get fuzzy. Clif Marriage is a relationship in which one person is always right and the other is usually the husband. > > The text in the body of the article was not a problem to read - it's the > little stuff in the chart that's a challenge . > Bet your OCR software can't figure that stuff out. > ________________________________ Message 42 ____________________________________ Time: 07:54:14 PM PST US From: Jeff Boatright Subject: Pietenpol-List: Re: Jay Anderson prop Ryan, Sorry, had a long day of work and chores, but ended up at the airport practicing wheelies in the Piet. Not a bad day! We had a 70x38 Valley Engineering/Culver prop originally. It did OK, giving us a solid 6-700 fpm climb with the C-85. Switched to a Cloudcars (Jay Anderson) 76x38, which easily gave 850-900 fpm. There is A LOT more thrust. Another "measure" is that at idle the old prop didn't pull the plane forward. With the new prop, the plane will actually pull up a modest hill at idle! Plus, the new prop looks cool and sounds mean! Our wire wheels are only 17" diameter, so with tires only 21" diameter total. That's actually not all that tall. I wish we had 21" wheels and 4" tires, mainly because we're not in a full stall in the three-point attitude. Sometimes I land tailwheel first. That said, ground clearance might be an issue for you. Check the Bingelis books or ask the list, but I think that in level attitude on the ground, the prop tip should be 9" above the ground. You could easily measure this once you have the fuselage on the gear and the engine hung. Jay at Cloudcars was easy to work with. You can sometimes get a discount if he already has a prop made up and he's looking to sell fast. That's how we got the 76X38, which he bills as a climb prop for an A65. With the C-85, it's a rocket prop. He offered to trade for something he thought was better matched for a C-85 if we didn't like the 76x38, but we like the climb rate and the top end revs are about the same and produce nearly identical speeds, so we kept it and we're very happy with it. HTH, Jeff At 2:17 PM -0500 10/20/09, Ryan Mueller wrote: >Good afternoon Jeff, > >My wife and I are building a Piet up near Chicago. We were going to >power it with a Corvair, but I stumbled across a good deal on a >relatively low-time A-65 while looking for Cub wheels, so we went >ahead and bought it. It was removed from a flying Cub for an engine >upgrade. Unfortunately it does not come with a prop, so I am >investigating our options there. A couple of people replied to a >question on the list this AM, saying that 72x42 appears to be the >standard Sensenich for the A65 on similar performing aircraft. Dan >Yocum pointed out to me that you and Gene (from the list, can't >recall the last name) both have Jay Anderson (Cloudcars) scimitar >props, and a look in the archives confirms both that and the fact >that you enjoy the performance. > >If you had a more "standard" prop on your Piet before, could you >elaborate on the differences in performance that the Jay Anderson >prop affords? The scimitar prop really looks sharp, and I just >wanted to get your synopsis of how it's worked for you thus far. If >I recall correctly, you have tall wire wheels on your Piet? Do you >recall if there was any potential concern about ground clearance >with a 4" longer prop than usual (assuming the 72" Sensenich is more >'usual')? Our Piet will be wearing 800x4 Piper Cub wheels, so we may >not have as much ground clearance when level as you do. > >Anyhow, any information you may be able to send our way would be >appreciated. Thanks for your time, and have a good day. > >Ryan Mueller -- --- Jeffrey H. Boatright, Ph.D. Associate Professor of Ophthalmology Emory University School of Medicine Editor-in-Chief Molecular Vision ________________________________ Message 43 ____________________________________ Time: 08:02:15 PM PST US From: "Dick N." Subject: Re: Pietenpol-List: Prop choices for A-65 Hi Skip I'm not Jack but I have an A-65 and Sensenich 72x42 also. I cruise at 75-76 mph, climb at 150-200 fpm. For anyone else, Culver Props does very nice work, is very customer responsive and much cheaper. I have one on the radial Piet. Dick N. ----- Original Message ----- From: Skip Gadd To: pietenpol-list@matronics.com Sent: Tuesday, October 20, 2009 8:28 PM Subject: RE: Pietenpol-List: Prop choices for A-65 Jack, What numbers do you get with the Sensenich? The reason I have been wanting one is because they do pretty good on Cubs, and they are nice and fat and user friendly for hand propping. Skip ----- Original Message ----- From: Jack Phillips To: pietenpol-list@matronics.com Sent: 10/20/2009 4:42:50 PM Subject: RE: Pietenpol-List: Prop choices for A-65 I've got a Sensenich 72-42 and am not all that happy with it. I have a St Croix 76-36 that I have never tried but will some day. Jack Phillips NX899JP Raleigh, NC ------------------------------------------------------------------------- --- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Skip Gadd Sent: Tuesday, October 20, 2009 10:09 AM To: pietenpol-list@matronics.com Subject: RE: Pietenpol-List: Prop choices for A-65 Ryan, Have had 2 props on Felix the GN-1, A-65, plane weighs 720 lbs. 1. McCauley Met-L-Prop 74-43. Climbs good can handle pac up to 220 if is not too hot. Cruse at 2150 68 to 70 MPH. Max RPM 2375. 2. Hegy I got from Don E. 72-44 Climbs not as good can handle pac up to 180. Curse at 1950 72 MPH. Max RPM 2150. Interestingly, the plane seems to get 3.8 GPH with ether prop. I would like to have a Sensenich 72-42. Skip ----- Original Message ----- From: Ryan Mueller To: pietenpol-list@matronics.com Sent: 10/20/2009 7:59:17 AM Subject: Pietenpol-List: Prop choices for A-65 Good morning all, There will be an A-65-8 making it's way to our shop in a couple of weeks. I am contemplating it's future. It is complete, and should be a runner; however it does not come with a prop. I would prefer to have a wood prop on the Piet. Can those of you that have wood props flying on A-65's on your Pietenpol's comment on the make, size, and pitch that you are running, or you experiences in the past with varying configurations? Thanks much, and have a good morning. Ryan <> http://www.matronics.com/Navigator?Pietenpol-Listhttp://forums.matronics. comhttp://www.matronics.com/contribution ________________________________ Message 44 ____________________________________ Time: 08:03:56 PM PST US From: "Dick N." Subject: Re: Pietenpol-List: Tail feather drain holes Hi Rick I put one next to each rib and on the rudder at the very bottom point. Dick N. ----- Original Message ----- From: "at7000ft" Sent: Tuesday, October 20, 2009 2:58 PM Subject: Pietenpol-List: Tail feather drain holes > > Question for anyone who has finished covering. How many drain grommets did > you put on your tail feather panels and where did you put them? > > Thanks > > Rick, busy rib lacing. > > -------- > Rick Holland > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=268710#268710 > > > ________________________________ Message 45 ____________________________________ Time: 08:26:55 PM PST US From: AMsafetyC@aol.com Subject: Re: Pietenpol-List: Re: lift struts for GN-1 /Pietenpol this is a long one That would be great, thanks. Not to diminish the important's of what's been said regarding the wooden struts. I believe 2 years ago at brodhead the Canadian Goose had wooden struts. They looked great. Mine are already made and are 3 linear layers of wood clear white ash in the middle with black walnut on the outer sandwich. They were laminated using the T88, clamped straight and allowed to set cure under clamp and Jig in a square shape larger than the streamline tubing. The lamination has metal imbedded into the middle of the lamination at 3 locations each and at the connection point of the jury strut to prevent the bolts from pulling out of thru or splitting out the wood. The struts were shaped using the dimensions of the tubing in the drawings except slightly wider and longer than the metal tubing. Understanding the relationship of the wing to the strut and relative loading and stresses created during normal flight. Here is where my non engineering background really comes into play. If there wing in normal condition exerts a static load of X lets say for argument sake x is = to 160 lbs over all. And at 8 loading connections two at the flying strut, 2 at the jury strut and 2 at the cabane struts that static load exerted by a non flying wing on the struts would be Y. Lets also assume in gross numbers the fuse at full capacity weighs 700 lbs. what is the static load on the struts? Now that we have a static load on the struts shared by all 8 connections not calculate the dynamic loads positive and negative or compression and extension in flight, that value being SL. The strut load would be that amount of weight or pressure that the strut system is required to support in and under normal flight conditions now to calculate side loads and combined loads to determine then highest amount of loading the struts will ever be exposed to by an aircraft who's total weight is 1000 lbs at full load and flying. That becomes the comparator for strut materials selection. The strut must be capable of handling loads of a value we call UL ultimate loading. Now we can look at the strut material separately as a beam or structural member and either copy form the materials book the load capacity of 4130 round and streamline, T6 aluminum round pipe or streamline, composite and laminated wood. All of which are arbitrary values based on none other than the design weights in the Bernerd POA specs section of the instructions. So if airplane 1 weighs 1050 at the curb how much stress will the struts be required to safely and regularly handle? Again not being a computer scientist, however just barely able to type a cogent paragraph my self. We are all using a device that is not less than 10,000 times more capable sophisticated and faster than the computers used to put a man on the moon. It sounds almost cook book type to come up with the equations that when we builders now and in the future want to look at a specific Piet design or system that we can punch in some easy numbers and get out an answer from the computer. Seems like with all the talent real and inferred that 2 engineers with AutoCAD to model and excel to come up with a series of questions that when answered with real data will provide an answer. At a bare minimum then the builder can select an amount of over build as a margin of safety and have a clue as to what's needed for his or her build. That's where I am going with this, there is no need for each of us to try to reinvent the wheel each time someone has an idea or a question that goes contrary to the conventional build or design. After all we are talking experimental here. The It Girl of the Sky put it best, " you're both starvin, why not try to help each other" Go in peace the service has ended No for the other news I just got my copy of Barnstormers and watched it a n hour ago, wow that was great I am impressed and want to be invited if I can survive my own creative experimental endeavors and the did pay homage to TGW when they looked towards the heavens and asked WWD? What Would Waldo Do the answer was a resounding the show must go on! John In a message dated 10/20/2009 10:28:42 P.M. Eastern Daylight Time, rray032003@gmail.com writes: I remember some one did this and there was a picture of the plane in the experimenter. I'll see if I can find the issue and get your address I will mail the picture to you if I can find it. Russell On Tue, Oct 20, 2009 at 9:44 PM, Bill Church <_billspiet@sympatico.ca_ (mailto:billspiet@sympatico.ca) > wrote: <_billspiet@sympatico.ca_ (mailto:billspiet@sympatico.ca) > John (PM Danger), Here I was, thinking that you wanted to know a simple method to determine whether a certain size of round 4130 tubing could be substituted for the 1934 special streamline tubing shown in the plans, and I was thinking about how there is NO SIMPLE ANSWER or formula to give, and then you tell us you're talking about wooden struts. There are so many variables (without even getting int the specifics of your unique plane)! There's the species of wood, the "quality" of the particular pieces of wood used, the size and shape of the struts, the thickness and number of laminations, the glue used, not to mention the "metal inserts". You mention that you are not an engineer. Well, as you know, I am an engineer, but I'm not an aeronautical engineer. Despite my background, I do not feel qualified to determine the suitability of wooden flying struts for my Piet, let alone someone else's. I think your best option would be to track down a builder that has successfully built and flown (for a significant amount of time) a wooden-strutted Piet, and borrow that design (if they are willing to share it with you). It sounds like you have built a set of struts based on "that looks about right". The flying struts are WAY too important to be approached in that manner. Like you say, a catastrophic failure in flight would really screw up your day. Be very careful with this stuff. As much as I like the look of wooden struts I will be using steel struts on my plane. Bill C. Read this topic online here: _http://forums.matronics.com/viewtopic.php?p=268755#268755_ (http://forums.matronics.com/viewtopic.php?p=268755#268755) s List Un/Subscription, www.matronics.com/Navigator?Pietenpol-List" target="_blank">http://www.matronics.com/Navigator?Pietenpol-List ronics.com/" target="_blank">http://forums.matronics.com Matt Dralle, List Admin. ==== (http://www.matronics.com/Navigator?Pietenpol-List) (http://www.matronics.com/contribution) ________________________________ Message 46 ____________________________________ Time: 10:11:05 PM PST US From: "Steve Ruse" Subject: Pietenpol-List: Prince Q-tip prop for sale for A-75 w/tapered shaft - 68x42 New this prop is about $1,900 according to the Prince website, it was custom made for a Pietenpol. I'd sell it for a lot less than $1,900. Does anyone need a prop for an A-75? It is in near new condition, and probably has less than 100hrs on it, although I don't know the exact number. If anyone is interested I'll take some good quality pictures, just send me an e-mail - steve@wotelectronics.com. It turns about 2,500 static on my A-75 I believe. Here is a picture from a few years ago, it is not on the plane now: http://www.wotelectronics.com/flying/GN1/dsc24.jpg Manufacturer: http://www.princeaircraft.com/ Steve Ruse Norman, OK ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message pietenpol-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/Pietenpol-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/pietenpol-list Browse Digests http://www.matronics.com/digest/pietenpol-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.