---------------------------------------------------------- Pietenpol-List Digest Archive --- Total Messages Posted Sat 03/13/10: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 01:09 AM - Re: Re: New builder already needs help (Clif Dawson) 2. 04:43 AM - Re: 1/2" web idea. Spar options--one man's method (Jack) 3. 05:11 AM - Re: 1/2" web idea. Spar options--one man's method (bryan green) 4. 05:41 AM - Re: Re: 1/2" web idea. Spar options--one man's method (Jack) 5. 06:35 AM - Rib Stitching Tail Surfaces (gliderx5@comcast.net) 6. 06:50 AM - Re: Re: 1/2" web (Gene Rambo) 7. 08:06 AM - Re: Rib Stitching Tail Surfaces (Jim Ash) 8. 09:02 AM - Re: Rib Stitching Tail Surfaces (David Paule) 9. 09:32 AM - Re: Re: 1/2" web idea. Spar options--one man's method (bryan green) 10. 10:03 AM - Re: Rib Stitching Tail Surfaces (Skip Gadd) 11. 12:47 PM - Re: Rib Stitching Tail Surfaces (Ben Charvet) 12. 03:52 PM - Re: Rib Stitching Tail Surfaces (Jack Phillips) 13. 04:38 PM - Re: Rib Stitching Tail Surfaces (Don Emch) 14. 04:45 PM - Re: Rib Stitching Tail Surfaces (Rick Holland) 15. 04:59 PM - Re: Rib Stitching Tail Surfaces (helspersew@aol.com) 16. 05:53 PM - Piet search (Lawrence Williams) 17. 05:54 PM - V speeds (Jeff Boatright) 18. 06:59 PM - OT - TGWP (Wayne Bressler) ________________________________ Message 1 _____________________________________ Time: 01:09:43 AM PST US From: "Clif Dawson" Subject: Re: Pietenpol-List: Re: New builder already needs help What was the orientation of the web plywood grain? The Piet spar is 4 3/4" wide. What you are going to remove is 3 1/2" of that 1/4" deep on both sides. The length of the routed areas will be close to 12' on each side of the fuselage. There are two spars, one front, one rear, so eight of these routed areas. This comes to 1008 cubic inches. There are 1728 cubic inches in a cubic foot. One cubic ft of spruce weighs 31 lb. This all means that there will be eighteen pounds of wood removed. Each of us then has to ask, " Is this important to me?" The only way to be experimentaly sure is to weight the board BEFORE routing and again after, not trying to collect what dust and chips you can find on the floor. Your router sprays stuff all over the shop grasshopper. :-) Clif "If we love flying so much why are we in a hurry to get there?" > When I worked for Steen Aero, the company airplane (Hale Wallace's last > Skybolt, N3HW) had routed spars. While it's never had problems, Hale and > others agreed (after the fact) that it was a fundamental mistake to do > this. > In the end you only save a very small amount of weight (I think it was > under > 2 lbs, even for a biplane), and it can (potentially) significantly reduce > the rigidity of the spars. You also risk messing up while doing the > routing > process and converting the piece to very expensive scrap wood!! Obviously > it's worked on many aircraft over the decades, but really, why risk it for > such a miniscule advantage and high potential cost? > > I'd say that if you really want the beefiness of 1" spars but the lighter > weight of 3/4" spars, you'd be better off making your spars 7/8" thick, > without routing them. Or not worrying about it and going with the 1"... > seems to me that the spar is one of those things where a little extra > strength really isn't a bad thing at all, and the weight difference would > be > better made up on other things. On my project, I believe I'll probably end > up with laminated spars, as this reduces the chances of a hidden defect > buried in the wood, you can use shorter wood pieces, they weight the same, > they fail progressively rather than completely at once (hopefully that > will > never be an issue!) and they are more warp-resistant. Strength is at least > as strong as a solid spar, and with the tests from the Skybolt laminated > spars, it was found they were usually about 25% stronger than the solid > versions. > > Mike Whaley > MerlinFAC@cfl.rr.com > > > ----- Original Message ----- > From: "Rick Holland" > To: > Sent: Friday, March 12, 2010 12:31 PM > Subject: [piet] Re: Pietenpol-List: Re: New builder already needs help > > >> >> Either size works fine. I think someone on this group who routed his >> 1" spars collected and weighted the shavings he routed out to see how >> much weight he saved, came to less than a pound I believe. Can be >> found in the archives. >> >> rick >> >> On Fri, Mar 12, 2010 at 12:00 PM, Bill Church > wrote: > >> > >> > Myron, >> > >> > If you purchased the full set of Pietenpol plans (including the > three-piece wing plan), you will see both versions of the spar (1" thick, > and 3/4" thick). The original design was 1" thick, with routed sections to > reduce weight. This was the spar drawn in the FGM drawings as well as in > the > 1933/34 Improved Air Camper drawings. Later, BHP switched to a 3/4" thick > spar, with NO routed sections. The 3/4" spar is only shown in the drawing > for the three-piece wing. The 3/4" non-routed spar has approximately 90% > the > strength of the routed 1" spar (in simple bending). Both have been proven > to > be more than adequate in strength. >> > Which one to use is strictly up to you. >> > Your ribs can be built to accommodate the 1" spar, and then, later, if > you decide to use 3/4" spars, just add 1/2" wide, 1/8" plywood spacer > shims > at each rib location. Or, if you know for certain that you want to use the > 3/4" spar, build your ribs to suit, and eliminate the little bit of extra > weight and work of the shims. >> > >> > Bill C. >> > >> > >> > >> > >> > Read this topic online here: >> > >> > http://forums.matronics.com/viewtopic.php?p=290119#290119 >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> > >> >> >> >> -- >> Rick Holland >> Castle Rock, Colorado >> >> "Logic is a wreath of pretty flowers, that smell bad" >> >> >> >> >> >> > > -------------------------------------------------------------------------------- Checked by AVG - www.avg.com 11:33:00 ________________________________ Message 2 _____________________________________ Time: 04:43:36 AM PST US From: "Jack" Subject: RE: Pietenpol-List: 1/2" web idea. Spar options--one man's method This is how I did it. An engineering friend thought the strength would be fine. He also thought the wider cap on top would help because caps usually break in compression first. I'm not an engineer! More pictures on my site Jack www.textors.com DSM Myron, Group----here is how I did my spar and how I would do it again proposed in the attached sketch. I did a cost analysis of both methods and it was pretty much a wash as I recall with the proposed method being way less work by not having to route out U-channels in those upper and lower 'caps'. Mike C. ________________________________ Message 3 _____________________________________ Time: 05:11:02 AM PST US From: "bryan green" Subject: Re: Pietenpol-List: 1/2" web idea. Spar options--one man's method Hi Jack, what did you do at each rib location? Bryan Green Elgin SC ----- Original Message ----- From: "Jack" Sent: Saturday, March 13, 2010 7:24 AM Subject: RE: Pietenpol-List: 1/2" web idea. Spar options--one man's method > This is how I did it. An engineering friend thought the strength would be > fine. He also thought the wider cap on top would help because caps > usually > break in compression first. I'm not an engineer! More pictures on my > site > Jack > www.textors.com > DSM > > Myron, Group----here is how I did my spar and how I would do it again > proposed in the attached sketch. > > I did a cost analysis of both methods and it was pretty much a wash as I > recall with the proposed method > being way less work by not having to route out U-channels in those upper > and > lower 'caps'. > > Mike C. > > > ________________________________ Message 4 _____________________________________ Time: 05:41:48 AM PST US From: "Jack" Subject: RE: Re: Pietenpol-List: 1/2" web idea. Spar options--one man's method Bryan, Not sure what your mean...I glued the ribs at the caps and didn't fill behind uprights. Jack Hi Jack, what did you do at each rib location? Bryan Green Elgin SC ----- Original Message ----- From: "Jack" Sent: Saturday, March 13, 2010 7:24 AM Subject: RE: Pietenpol-List: 1/2" web idea. Spar options--one man's method > This is how I did it. An engineering friend thought the strength would be > fine. He also thought the wider cap on top would help because caps > usually > break in compression first. I'm not an engineer! More pictures on my > site > Jack > www.textors.com > DSM > > Myron, Group----here is how I did my spar and how I would do it again > proposed in the attached sketch. > > I did a cost analysis of both methods and it was pretty much a wash as I > recall with the proposed method > being way less work by not having to route out U-channels in those upper > and > lower 'caps'. > > Mike C. > > > ________________________________ Message 5 _____________________________________ Time: 06:35:35 AM PST US From: gliderx5@comcast.net Subject: Pietenpol-List: Rib Stitching Tail Surfaces I'm starting to cover the Piet. I'm using light weight cloth and Stewart Systems ecobond. This glue is great. Easy to use and no bad odor. I'm at the point now where I need to rib stitch the tail surfaces, but I'm wondering if this is really needed. The fabric is glued to the 1/2 inch wide tail ribs, and while there will be some pulling of the fabric on the low pressure side of the surfaces, it will not be anything close to low pressure on the top of the wing. So, have any of you guys not stitched your tail surfaces? And if so, do you have any good or bad results after flying? Thanks Malcolm Morrison ________________________________ Message 6 _____________________________________ Time: 06:50:38 AM PST US From: "Gene Rambo" Subject: Re: Re: Pietenpol-List: 1/2" web About a year ago when I priced it from both Wicks and Aircraft Spruce, the cost of the 1/2" center with four 1" x 1/4" capstrips was more than the cost of the solid spars, so I went solid and routed. Of course, the plywood center web may be cheaper, I did not price that. One question I could never get a good answer to is how/where the proper splices would be (building a one-piece wing). I would think that they could be anywhere as long as they were staggered. Of course, this would not be a problem if building a 3-piece where all of the components could be full length without splices. I like the built-up spars, the examples on here are beautiful, but cheaper and more original won out. Unfortunately, I did not weigh before and after routing, but I can tell you that the weight saving is substantial, not miniscule as some on here have suggested. Pietenpol says 25% and I think that is probably right. If it is wrong, it is low. Gene ________________________________ Message 7 _____________________________________ Time: 08:06:47 AM PST US From: Jim Ash Subject: Re: Pietenpol-List: Rib Stitching Tail Surfaces These surfaces are in the propwash and subject to piles of vibration. I'm not familiar with the Stewart System (I've done Polyfiber), but I'd be inclined to think a glue joint would be naturally better in compression and shear than in tension (I don't really know if this is a valid assumption - Does anybody here have experience with analysis of the strengths of adhesives?). Stitching is primarily about tension. While we're on this, I'm going to presume the Stewart System requires a closer pitch of stitching on the inner portions of the wing subject to propwash. Jim Ash -----Original Message----- From: gliderx5@comcast.net Sent: Mar 13, 2010 9:19 AM Subject: Pietenpol-List: Rib Stitching Tail Surfaces I'm starting to cover the Piet. I'm using light weight cloth and Stewart Systems ecobond. This glue is great. Easy to use and no bad odor. I'm at the point now where I need to rib stitch the tail surfaces, but I'm wondering if this is really needed. The fabric is glued to the 1/2 inch wide tail ribs, and while there will be some pulling of the fabric on the low pressure side of the surfaces, it will not be anything close to low pressure on the top of the wing. So, have any of you guys not stitched your tail surfaces? And if so, do you have any good or bad results after flying? Thanks Malcolm Morrison ________________________________ Message 8 _____________________________________ Time: 09:02:13 AM PST US From: "David Paule" Subject: Re: Pietenpol-List: Rib Stitching Tail Surfaces Bingo! Strength in tension is often less if the tension is in "peel," which it is for fabric covering. David Paule > > These surfaces are in the propwash and subject to piles of vibration. I'm not familiar with the Stewart System (I've done Polyfiber), but I'd be inclined to think a glue joint would be naturally better in compression and shear than in tension (I don't really know if this is a valid assumption - Does anybody here have experience with analysis of the strengths of adhesives?). Stitching is primarily about tension. ________________________________ Message 9 _____________________________________ Time: 09:32:55 AM PST US From: "bryan green" Subject: Re: Re: Pietenpol-List: 1/2" web idea. Spar options--one man's method Thats what I wanted to know Jack thanks. do not archive Bryan Green Elgin SC ----- Original Message ----- From: "Jack" Sent: Saturday, March 13, 2010 8:37 AM Subject: RE: Re: Pietenpol-List: 1/2" web idea. Spar options--one man's method > Bryan, > Not sure what your mean...I glued the ribs at the caps and didn't fill > behind uprights. > Jack > > > > Hi Jack, what did you do at each rib location? > Bryan Green > Elgin SC > ----- Original Message ----- > From: "Jack" > To: > Sent: Saturday, March 13, 2010 7:24 AM > Subject: RE: Pietenpol-List: 1/2" web idea. Spar options--one man's method > > >> This is how I did it. An engineering friend thought the strength would >> be >> fine. He also thought the wider cap on top would help because caps >> usually >> break in compression first. I'm not an engineer! More pictures on my >> site >> Jack >> www.textors.com >> DSM >> >> Myron, Group----here is how I did my spar and how I would do it again >> proposed in the attached sketch. >> >> I did a cost analysis of both methods and it was pretty much a wash as I >> recall with the proposed method >> being way less work by not having to route out U-channels in those upper >> and >> lower 'caps'. >> >> Mike C. >> >> >> > > > ________________________________ Message 10 ____________________________________ Time: 10:03:34 AM PST US From: "Skip Gadd" Subject: RE: Pietenpol-List: Rib Stitching Tail Surfaces Malcolm, Rib stitching is not only about holding the fabric to the ribs, but also about holding the top cap strip together with the bottom cap strip. This is very important when talking about a truss built rib. Not really sure about the tail surfaces, but I will be stitching mine. Skip ----- Original Message ----- From: Sent: 3/13/2010 9:37:21 AM Subject: Pietenpol-List: Rib Stitching Tail Surfaces I'm starting to cover the Piet. I'm using light weight cloth and Stewart Systems ecobond. This glue is great. Easy to use and no bad odor. I'm at the point now where I need to rib stitch the tail surfaces, but I'm wondering if this is really needed. The fabric is glued to the 1/2 inch wide tail ribs, and while there will be some pulling of the fabric on the low pressure side of the surfaces, it will not be anything close to low pressure on the top of the wing. So, have any of you guys not stitched your tail surfaces? And if so, do you have any good or bad results after flying? Thanks Malcolm Morrison ________________________________ Message 11 ____________________________________ Time: 12:47:55 PM PST US From: Ben Charvet Subject: Re: Pietenpol-List: Rib Stitching Tail Surfaces I used Stewart System with the lightweight cloth, and I rib stitched the tail surfaces, without gluing the fabric to the ribs. It really doesn't take very long. After hearing horror stories about how tedious rib-stitching was, I found it to be enjoyable. I don't think rib stitching the tail surfaces would take more than a few hours. Might make the job look more professional to your inspector too. Just my $.02 Ben Charvet Flyin off the time! On 3/13/2010 9:19 AM, gliderx5@comcast.net wrote: > I'm starting to cover the Piet. I'm using light weight cloth and > Stewart Systems ecobond. This glue is great. Easy to use and no bad > odor. I'm at the point now where I need to rib stitch the tail > surfaces, but I'm wondering if this is really needed. The fabric is > glued to the 1/2 inch wide tail ribs, and while there will be some > pulling of the fabric on the low pressure side of the surfaces, it > will not be anything close to low pressure on the top of the wing. > So, have any of you guys not stitched your tail surfaces? And if so, > do you have any good or bad results after flying? > > Thanks > Malcolm Morrison > * > > > * ________________________________ Message 12 ____________________________________ Time: 03:52:51 PM PST US From: "Jack Phillips" Subject: RE: Pietenpol-List: Rib Stitching Tail Surfaces I stitched mine. Good practice for doing the wings. Jack Phillips NX899JP Raleigh, NC _____ From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of gliderx5@comcast.net Sent: Saturday, March 13, 2010 9:20 AM Subject: Pietenpol-List: Rib Stitching Tail Surfaces I'm starting to cover the Piet. I'm using light weight cloth and Stewart Systems ecobond. This glue is great. Easy to use and no bad odor. I'm at the point now where I need to rib stitch the tail surfaces, but I'm wondering if this is really needed. The fabric is glued to the 1/2 inch wide tail ribs, and while there will be some pulling of the fabric on the low pressure side of the surfaces, it will not be anything close to low pressure on the top of the wing. So, have any of you guys not stitched your tail surfaces? And if so, do you have any good or bad results after flying? Thanks Malcolm Morrison ________________________________ Message 13 ____________________________________ Time: 04:38:59 PM PST US Subject: Pietenpol-List: Re: Rib Stitching Tail Surfaces From: "Don Emch" Good insurance to stitch them. That tail surface fabric does drum a lot. Only a few hours worth of work. Don Emch NX899DE Read this topic online here: http://forums.matronics.com/viewtopic.php?p=290233#290233 ________________________________ Message 14 ____________________________________ Time: 04:45:56 PM PST US Subject: Re: Pietenpol-List: Rib Stitching Tail Surfaces From: Rick Holland Ditto rick On Sat, Mar 13, 2010 at 3:44 PM, Ben Charvet wrote: > I used Stewart System with the lightweight cloth, and I rib stitched the > tail surfaces, without gluing the fabric to the ribs. It really doesn't > take very long. After hearing horror stories about how tedious > rib-stitching was, I found it to be enjoyable. I don't think rib stitching > the tail surfaces would take more than a few hours. Might make the job look > more professional to your inspector too. Just my $.02 > > Ben Charvet > Flyin off the time! > > > On 3/13/2010 9:19 AM, gliderx5@comcast.net wrote: > > I'm starting to cover the Piet. I'm using light weight cloth and Stewart > Systems ecobond. This glue is great. Easy to use and no bad odor. I'm at > the point now where I need to rib stitch the tail surfaces, but I'm > wondering if this is really needed. The fabric is glued to the 1/2 inch > wide tail ribs, and while there will be some pulling of the fabric on the > low pressure side of the surfaces, it will not be anything close to low > pressure on the top of the wing. So, have any of you guys not stitched your > tail surfaces? And if so, do you have any good or bad results after flying? > > Thanks > Malcolm Morrison > > > href="http://www.matronics.com/Navigator?Pietenpol-List">http://www.matronics.com/Navigator?Pietenpol-List > href="http://forums.matronics.com">http://forums.matronics.com > > href="http://www.matronics.com/contribution">http://www.matronics.com/contribution > > -- Rick Holland Castle Rock, Colorado "Logic is a wreath of pretty flowers, that smell bad" ________________________________ Message 15 ____________________________________ Time: 04:59:14 PM PST US Subject: Re: Pietenpol-List: Rib Stitching Tail Surfaces From: helspersew@aol.com Rib stitching is actually fun, after you learn it...........very therapeut ic, I enjoyed it immensely. Open the hangar doors.........let the summer breezes waft through........turn on the radio..........pop open a beer... ........Ahhhhhhhh, .....the good life..........not too many beers though, otherwise you may step on the cord, and tear your fabric. (not that I kno w this from experience, someone told me) :O) Dan Helsper Poplar Grove, IL. -----Original Message----- From: Jack Phillips Sent: Sat, Mar 13, 2010 5:19 pm Subject: RE: Pietenpol-List: Rib Stitching Tail Surfaces I stitched mine. Good practice for doing the wings. Jack Phillips NX899JP Raleigh, NC From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-li st-server@matronics.com] On Behalf Of gliderx5@comcast.net Sent: Saturday, March 13, 2010 9:20 AM Subject: Pietenpol-List: Rib Stitching Tail Surfaces I'm starting to cover the Piet. I'm using light weight cloth and Stewart Systems ecobond. This glue is great. Easy to use and no bad odor. I'm at the point now where I need to rib stitch the tail surfaces, but I'm wo ndering if this is really needed. The fabric is glued to the 1/2 inch wid e tail ribs, and while there will be some pulling of the fabric on the low pressure side of the surfaces, it will not be anything close to low press ure on the top of the wing. So, have any of you guys not stitched your ta il surfaces? And if so, do you have any good or bad results after flying? Thanks Malcolm Morrison http://www.matronics.com/Navigator?Pietenpol-List http://forums.matronics.com http://www.matronics.com/contribution ======================== =========== -= - The Pietenpol-List Email Forum - -= Use the Matronics List Features Navigator to browse -= the many List utilities such as List Un/Subscription, -= Archive Search & Download, 7-Day Browse, Chat, FAQ, -= Photoshare, and much much more: - -= --> http://www.matronics.com/Navigator?Pietenpol-List - -======================== ======================== =========== -= - MATRONICS WEB FORUMS - -= Same great content also available via the Web Forums! - -= --> http://forums.matronics.com - -======================== ======================== =========== -= - List Contribution Web Site - -= Thank you for your generous support! -= -Matt Dralle, List Admin. -= --> http://www.matronics.com/contribution -======================== ======================== =========== ________________________________ Message 16 ____________________________________ Time: 05:53:13 PM PST US From: Lawrence Williams Subject: Pietenpol-List: Piet search Idle curiousity on a cool and windy eve. - I had a good friend named John Ficklin-who built and finished an Air Camp er in northern FL around 2000-2002. Unfortunately he-had to sell-it pre tty quickly after it's completion and I was wondering if anyone on the list has it or knows where it might be. - Larry W.=0A=0A=0A ________________________________ Message 17 ____________________________________ Time: 05:54:30 PM PST US From: Jeff Boatright Subject: Pietenpol-List: V speeds Just because it's too windy and rainy to fly today, I'm goint to stir the pot: What are you using for Vso, Vx, Vy, Vno, Vne, Vref, Va, etc. and what are your numbers based on? ________________________________ Message 18 ____________________________________ Time: 06:59:35 PM PST US From: Wayne Bressler Subject: Pietenpol-List: OT - TGWP A little paint? We are truly an infected bunch; those who love aviation. www.flyingantiqueairplanes.blogspot.com/2009/10/wheres-waldo.html This is from Don Parson's blog chronicaling the restoration of a Cub, and other antique airplane exploits. An interesting site to waste an hour or so. Wayne Bressler Jr. Taildraggers, Inc. taildraggersinc.com ------------------------------------------------------------------------------------- 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.