---------------------------------------------------------- Pietenpol-List Digest Archive --- Total Messages Posted Mon 01/26/04: 35 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:58 AM - Re: Re:New Pictures (BARNSTMR@aol.com) 2. 07:09 AM - more airfoil talk (Ken Chambers) 3. 08:01 AM - Re: more airfoil talk (Isablcorky@aol.com) 4. 08:29 AM - Re: corvair conversion cost (DJ Vegh) 5. 08:36 AM - Re: corvair conversion cost (Andimaxd@aol.com) 6. 09:18 AM - Re: Re: Tail Volume (John Dilatush) 7. 09:18 AM - Re: corvair conversion cost (Mike) 8. 10:24 AM - Re: corvair conversion cost (DJ Vegh) 9. 10:54 AM - Re: Re: Tail Volume (Christian Bobka) 10. 11:03 AM - dead soft stainless and aluminum (Michael D Cuy) 11. 11:51 AM - Re: Re: Tail Volume (DJ Vegh) 12. 01:19 PM - Re: Rib jig (Deon Engelmann) 13. 02:04 PM - Re: Rib jig (Jim Markle) 14. 05:25 PM - Re: More new pictures from 40-yr-old Piet (hjarrett) 15. 05:25 PM - Re: more airfoil talk (hjarrett) 16. 05:49 PM - Re: More new pictures from 40-yr-old Piet (hjarrett) 17. 05:54 PM - Front Seat Support (dpaul) 18. 06:21 PM - Re: Front Seat Support (Greg Cardinal) 19. 07:24 PM - Re: corvair conversion cost (Alex Sloan) 20. 07:37 PM - Re: corvair conversion cost (Alex Sloan) 21. 07:37 PM - Re: Rib jig (Rcaprd@aol.com) 22. 07:39 PM - Re: Re: Tail Volume (John Dilatush) 23. 07:48 PM - Re: dead soft stainless and aluminum (Alex Sloan) 24. 08:12 PM - Re: more airfoil talk (Rcaprd@aol.com) 25. 08:15 PM - Re: Rib jig (Alex Sloan) 26. 08:18 PM - Re: more airfoil talk (Rcaprd@aol.com) 27. 08:27 PM - maybe where the FC-10 came from........ (Jim Markle) 28. 08:31 PM - Re: corvair conversion cost (Rcaprd@aol.com) 29. 08:53 PM - PLYWOOD REQUIREMENTS (Richard Schreiber) 30. 08:55 PM - Re: Re: Tail Volume (Rcaprd@aol.com) 31. 09:26 PM - Re: Rib jig 2 (Deon Engelmann) 32. 09:50 PM - Seeking Piet ride at Sun N Fun (Mike Whaley) 33. 10:22 PM - Re: PLYWOOD REQUIREMENTS (Catdesign) 34. 10:26 PM - Re: Front Seat Support (Catdesign) 35. 11:26 PM - Re: Rib jig 2 (Rcaprd@aol.com) ________________________________ Message 1 _____________________________________ Time: 06:58:04 AM PST US From: BARNSTMR@aol.com Subject: Re: Pietenpol-List: Re:New Pictures --> Pietenpol-List message posted by: BARNSTMR@aol.com In a message dated 1/25/2004 10:27:51 PM Eastern Standard Time, bconoly@earthlink.net writes: > If anybody is interested, we started covering last > weekend.... Bert, Intrerested? Nawwww...not here. Ha Those are great pics. Looks like you really went to town this weekend. I am looking forward to glueing fabric hopefully in a few weeks. Nice website too. Terry L. Bowden ph 254-715-4773 fax 254-853-3805 ________________________________ Message 2 _____________________________________ Time: 07:09:03 AM PST US Subject: Pietenpol-List: more airfoil talk From: "Ken Chambers" I've poked around a little on the Internet, trying to weasel some airfoil recommendations from knowledgeable folk. Just to keep us talking about it, give us some ideas. David Lednicer, who seems to have some pretty nice aerodynamic bona fides and works for Analytical Methods, Inc., thinks we should keep it simple with NACA 2412 or 4412. Proven airfoils with well-known characteristics. Used for years in a variety of Cessnas and other aircraft. I haven't had a chance to find the stats for these airfoils so we can compare them to the Pietenpol FC-10. Anyone know where to find this information online? Ken ________________________________ Message 3 _____________________________________ Time: 08:01:06 AM PST US From: Isablcorky@aol.com Subject: Re: Pietenpol-List: more airfoil talk Ken, Am Interested in further airfoil talk. It has been my plan to build two sets of wings for 311CC for a little experimentation. I don't really have anything else to do and am hoping that I have enough time left to carry it out. I have acquired the stations and ordinates in % of chord for the wing airfoil NACA 2412. Strange you mention that one. It's high lift and less drag than the FC-10. Won't know for sure until Test Pilot Mr. Edwin Johnson gives me his report sometimes in 2005. Anyway it makes good conversation on the net and educates a few of us. Corky in La trying to give away his almost completed 1927 Dodge Bros Station Wagon ________________________________ Message 4 _____________________________________ Time: 08:29:21 AM PST US From: "DJ Vegh" Subject: Re: Pietenpol-List: corvair conversion cost So far I'm at about $6500. The breakdown is like this: 0 hours rebuilt 110hp 1965 Corvair engine $4000 remote oil cooler,lines, filter, AN hose fittings $600. Tennesee Prop 48 lamination maple prop 66x29 $550 AeroCarb $400 Aluminum intake pipes/welding $350 misc hardware and other items $600 Not bad for a 0 time 6 cylinder 1800TBO 100hp engine. The rebuild consisted of all new pistons, cam, lifters, valves, valve guides, valve springs, fuel pump, oil pump, distributor (dual points), rings and main/rod bearings. The rebuilt items were rods, cylinders,crankshaft, harmonic balancer, heads. Other new items were Nissan Sentra starter and ring gear, William Wynne prop hub & lightweight oil pan, CNC cut top cover. Once I started assembly it took me approx 3 weeks to have the engine on the test stand and running. So far I have 13 hours on it. DJ Vegh www.imagedv.com/aircamper ----- Original Message ----- From: Brants Subject: Pietenpol-List: corvair conversion cost Anyone out there willing to share what money they have into their corvair conversion? Just trying to get a rough idea so I can channel my limetted building funds appropriately. Thanks, Tom Brant Brooklyn Park, MN = This email has been scanned for known viruses and made safe for viewing by Half Price Hosting, a leading email and web hosting provider. For more information on an anti-virus email solution, visit . ________________________________ Message 5 _____________________________________ Time: 08:36:31 AM PST US From: Andimaxd@aol.com Subject: Re: Pietenpol-List: corvair conversion cost Tom: I have it on good authority that starters are for sissy's !! Max ________________________________ Message 6 _____________________________________ Time: 09:18:23 AM PST US From: "John Dilatush" Subject: Re: Pietenpol-List: Re: Tail Volume --> Pietenpol-List message posted by: "John Dilatush" ----- Original Message ----- From: "Christian Bobka" Subject: Re: Pietenpol-List: Re: Tail Volume > --> Pietenpol-List message posted by: "Christian Bobka" =============================== Chuck and Chris, My research. and then after also consulting with a good friend who is an aeronautical engineer confirmed my impression that an undercambered airfoil is not likely to have a downward pitching moment. As defined in the books, a negative pitching moment is a moment which forces the leading edge of an airfoil UPWARD with increasing angles of attack not down as you imply. This then, doesn't appear to be the answer for the rearward CG that the Pietenpol uses. Not trying to be a smart ass, just trying to correct a misconception of terms. John ==================================== > Chuck, > > Excellent observation. I have no data on the Navion but will look later. > The Type Certificate Data Sheets are available on the FAA website. > > Chris > ----- Original Message ----- > From: > To: > Sent: Saturday, January 24, 2004 4:03 PM > Subject: Re: Pietenpol-List: Re: Tail Volume > > > > > > --> Pietenpol-List message posted by: Rcaprd@aol.com > > > > In a message dated 1/24/04 11:22:51 AM Central Standard Time, > > bobka@compuserve.com writes: > > > > << So the piet's airfoil must fall somewhere between what is common today > and > > a zero pitching moment airfoil. > > >> > > > > The Pietenpol, as well as any undercambered airfoil, has a lot of negative > > pitching moment (nose down). I believe this is why the Piet is somewhat > > tolorant of an aft C.G. That's the thing I've always been curious about, > is why > > Pietenpols are more forgiving for an aft C.G. condition. B.H.P called out > 1/3 > > (33.3%) of the chord, as the aft limit. I've never seen, or heard of any > other > > plane with the aft C.G. limit that far back. Most designs call out no > more > > than 30% of the chord for the aft limit, but they are not undercambered. > > (Tailwind calls out 28% as the aft C.G. limit). I think this is because > an > > undercambered airfoil has such a high negative pitching moment, that it is > more > > forgiving of an aft C.G. I've tried unsuccessfully to find the aft C.G. > limit of > > planes like the Jenny, but it is a Biplane - difficult to compare. > Another > > design that has an undercambered airfoil is the Ryan Navion. Does anyone > have the > > C.G. range of the Ryan Navion, or any other plane that has an > undercambered > > airfoil ? > > > > Chuck Gantzer > > NX770CG > > > > > > > > > > > > > > > > ________________________________ Message 7 _____________________________________ Time: 09:18:23 AM PST US Subject: Re: Pietenpol-List: corvair conversion cost From: Mike Yeah, tall sissies with both arms and both legs, despite flying low-slung airplanes like Piets. on 1/26/04 8:36, Andimaxd@aol.com at Andimaxd@aol.com wrote: Tom: I have it on good authority that starters are for sissy's !! Max ________________________________ Message 8 _____________________________________ Time: 10:24:18 AM PST US From: "DJ Vegh" Subject: Re: Pietenpol-List: corvair conversion cost are you implying that a Corvair must have a starter? ----- Original Message ----- From: Andimaxd@aol.com Subject: Re: Pietenpol-List: corvair conversion cost Tom: I have it on good authority that starters are for sissy's !! Max = This email has been scanned for known viruses and made safe for viewing by Half Price Hosting, a leading email and web hosting provider. For more information on an anti-virus email solution, visit . ________________________________ Message 9 _____________________________________ Time: 10:54:16 AM PST US From: "Christian Bobka" Subject: Re: Pietenpol-List: Re: Tail Volume --> Pietenpol-List message posted by: "Christian Bobka" John, From "Simple Aerodynamics" by Charles Monteith, April 1924, a text book used at West Point, page 72 says, "When an airfoil is at the angle of attack of zero lift, there is a download on the front part of the airfoil and an up load on the rear portion, which manifests itself as a negative or diving moment." On the undercambered RAF-15 airfoil, the CP in % of chord plot is as follows: AOA CP 0 49 2 38 4 34 6 31 8 30 10 29 12 30 14 34 This is a very shallow CP plot meaning that there is small shift in the CP with changes in AOA As long as the CG is forward of the CP, ignoring a few other unimportant to this discussion factors, it is obvious that the lifting forces are summed behind the CG. This would couse the nose to go down "which manifests itself as a negative or diving moment." The RAF 15 displays the characteristic movement of the CP forward as the a higher and higher AOA is achieved getting as far forward as 29% of chord at 10 degrees AOA. In comparison, the USA-35B, which is used on the J-3 Cub, has the following CP v AOA plot: AOA CP in % of chord -4 120 -3 70 -2 60 0 45 2 40 4 36 6 34 8 33 10 32 12 31 14 30 16 30.5 This is a very steep plot at the beginning meaing that as AOA decreases, the CP moves way aft. As a matter of fact the plot I looked at shows the CP to be 20% behind the wing trailing edge at a -4 degree AOA! That is a negative pitching moment for you! I partially agree with your buddy. The pitching moment appears to be less traveled with the undercambered airfoil. But nose down is negative! Chris ----- Original Message ----- From: "John Dilatush" Subject: Re: Pietenpol-List: Re: Tail Volume > > --> Pietenpol-List message posted by: "John Dilatush" > > > ----- Original Message ----- > From: "Christian Bobka" > To: > Sent: Saturday, January 24, 2004 3:35 PM > Subject: Re: Pietenpol-List: Re: Tail Volume > > > > --> Pietenpol-List message posted by: "Christian Bobka" > > =============================== > Chuck and Chris, > > My research. and then after also consulting with a good friend who is an > aeronautical engineer confirmed my impression that an undercambered airfoil > is not likely to have a downward pitching moment. > > As defined in the books, a negative pitching moment is a moment which forces > the leading edge of an airfoil UPWARD with increasing angles of attack not > down as you imply. > > This then, doesn't appear to be the answer for the rearward CG that the > Pietenpol uses. > > Not trying to be a smart ass, just trying to correct a misconception of > terms. > > John > ==================================== > > Chuck, > > > > Excellent observation. I have no data on the Navion but will look later. > > The Type Certificate Data Sheets are available on the FAA website. > > > > Chris > > ----- Original Message ----- > > From: > > To: > > Sent: Saturday, January 24, 2004 4:03 PM > > Subject: Re: Pietenpol-List: Re: Tail Volume > > > > > > > > > > --> Pietenpol-List message posted by: Rcaprd@aol.com > > > > > > In a message dated 1/24/04 11:22:51 AM Central Standard Time, > > > bobka@compuserve.com writes: > > > > > > << So the piet's airfoil must fall somewhere between what is common > today > > and > > > a zero pitching moment airfoil. > > > >> > > > > > > The Pietenpol, as well as any undercambered airfoil, has a lot of > negative > > > pitching moment (nose down). I believe this is why the Piet is somewhat > > > tolorant of an aft C.G. That's the thing I've always been curious > about, > > is why > > > Pietenpols are more forgiving for an aft C.G. condition. B.H.P called > out > > 1/3 > > > (33.3%) of the chord, as the aft limit. I've never seen, or heard of > any > > other > > > plane with the aft C.G. limit that far back. Most designs call out no > > more > > > than 30% of the chord for the aft limit, but they are not undercambered. > > > (Tailwind calls out 28% as the aft C.G. limit). I think this is > because > > an > > > undercambered airfoil has such a high negative pitching moment, that it > is > > more > > > forgiving of an aft C.G. I've tried unsuccessfully to find the aft C.G. > > limit of > > > planes like the Jenny, but it is a Biplane - difficult to compare. > > Another > > > design that has an undercambered airfoil is the Ryan Navion. Does > anyone > > have the > > > C.G. range of the Ryan Navion, or any other plane that has an > > undercambered > > > airfoil ? > > > > > > Chuck Gantzer > > > NX770CG > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > ________________________________ Message 10 ____________________________________ Time: 11:03:20 AM PST US From: Michael D Cuy Subject: Pietenpol-List: dead soft stainless and aluminum --> Pietenpol-List message posted by: Michael D Cuy Alex & group, I think the designation for dead soft is 000, but am not positive. I made my cooling eyebrow/baffles like Frank P. did using .025" dead soft aluminum and the firewall from the same but in stainless. Got both from Dillsburg Aeroplane Works, in PA. 717-432-4589. Mike ________________________________ Message 11 ____________________________________ Time: 11:51:57 AM PST US From: "DJ Vegh" Subject: Re: Pietenpol-List: Re: Tail Volume Chris, I just read your post about the need to add more tail volume if you extend the engine forward. A good point, but also consider when you move the wing aft you do two things... decrease tail moment and increase the distance ahead of the CG. A double edged sword. Moving the engine forward is the lesser of the two evils IMO. DJ = This email has been scanned for known viruses and made safe for viewing by Half Price Hosting, a leading email and web hosting provider. For more information on an anti-virus email solution, visit . ________________________________ Message 12 ____________________________________ Time: 01:19:15 PM PST US From: "Deon Engelmann" Subject: RE: Pietenpol-List: Rib jig Hi I looked, I listened and hopefully I learned. I took your advice in supporting the outside of the cap strips and rebuild the jig. Here are some updated pics. Comments? Deon Engelmann EAA322 Midrand # SA12055 Pretoria South Africa ________________________________ Message 13 ____________________________________ Time: 02:04:30 PM PST US From: Jim Markle Subject: RE: Pietenpol-List: Rib jig Wow, looks good to me! I found the thin clear plastic stuff that comes in rolls (sort of like clear plastic wrap) that's sticky on one side is great for keeping the epoxy from sticking to the jig. I think we got the stuff at the local home improvement center and it's typically used to stick on carpet while you're remodeling. Protects carpet very well...we used a LOT of it to cover the area under our kid's high chair when they were in the initial "learning to eat" process. My wife has even threatened to put it under my chair a time or two..... I've attached a picture that will give a bit of an idea of how it works. Really thin stuff and cheap.... One more thing...rather than having small blocks along the outside of the top and bottom (like the two shown in your picture), I would suggest making one long continuous piece along the top and one along the bottom. Wood won't follow the airfoil line perfectly in between those blocks but will stay a lot closer if it's held up against a solid curving surface. It's probably not enough to notice in flight, but it's easy enough to keep it close.... Deon, your jig/layout is really looking good! Jim in Plano..... -----Original Message----- From: Deon Engelmann Subject: RE: Pietenpol-List: Rib jig Hi I looked, I listened and hopefully I learned. I took your advice in supporting the outside of the cap strips and rebuild the jig. Here are some updated pics. Comments? Deon Engelmann EAA322 Midrand # SA12055 Pretoria South Africa ________________________________ Message 14 ____________________________________ Time: 05:25:18 PM PST US From: "hjarrett" Subject: Re: Pietenpol-List: More new pictures from 40-yr-old Piet The blue hue is usually from fluorescent lights. Incandescent lights will make the pictures a little yellow. Most people don't even notice, you must be picky or have really good color perception. By the way why is there an ear in the top right instrument hole? Is that the audio control? Hank J ----- Original Message ----- From: BARNSTMR@aol.com To: pietenpol-list@matronics.com Sent: Sunday, January 25, 2004 11:19 PM Subject: Pietenpol-List: More new pictures from 40-yr-old Piet Howdy all from Texas. Finally got a chance to work some more this weekend on the Piet. Also, added a few pics to the link below to fill in the progress made in the past few months.... slow but sure. http://www.mykitplane.com/Planes/photoGalleryList2.cfm?AlbumID188 Im not sure why, but all the pics have a blue hue to them. Makes us look like smurfs. Anysay, notice the spring gear re-build job done by my partner Lon Carr back in October. We are now very happy with a straight and true gear. The detail design of this gear is part Piet and part Hatz CB1. Today, I finally swallowed hard and got out that mean old fly-cutter and bored all the instrument holes in the rear panel. Had to do it on the ship since it was already permanently glued and nailed in place by the previous builder. Man that fly-cutter worked GREAT. Keys to a good job... 1) start with a sharp cutter tool. 2) keep a firm grip (used 14V Dewalt cordless drill) 3) keep a square alignment to the workpiece 4) don't cut slow...go ahead and cut fast enough to mell the smoke. 5) use a backing board (clamped) to prevent the farside last ply from tearing away. 6) Be safe. Use a removed front bezel from an old instrument as a drill guide for perfect alignment. Had a great weekend teaching my 9 yr-old stepson some sheet metal fabrication techniques. We built some channel stiffeners to bridge between the rear instrument and the front pit headrest. Also the ones forward of the front instrument panel. Added #8 nut plates for anchoring the cockpit cowlings. See also the attached pic. Those instruments really add some life. Since the original panel has some old stains from nails we have purchased some sticky-back wood veneer, which we will use to finish out the panel. Its getting closer...just slow. All the best. Terry Bowden ph (254) 715-4773 fax (254) 853-3805 ________________________________ Message 15 ____________________________________ Time: 05:25:18 PM PST US From: "hjarrett" Subject: Re: Pietenpol-List: more airfoil talk Information on the NACA airfoils is pretty easy to get. Good luck finding anything on BPs. That was why I suggested some wind tunnel testing by an Aero student. You can't do a comparison if you don't have data on all the airfoils. Best book to learn about aero theory I have found is by Abbott and Von Doenhoff. Gets a little deep every once in a while but fun to plow through. Hank J ----- Original Message ----- From: Ken Chambers To: pietenpol-list@matronics.com Sent: Monday, January 26, 2004 10:07 AM Subject: Pietenpol-List: more airfoil talk I've poked around a little on the Internet, trying to weasel some airfoil recommendations from knowledgeable folk. Just to keep us talking about it, give us some ideas. David Lednicer, who seems to have some pretty nice aerodynamic bona fides and works for Analytical Methods, Inc., thinks we should keep it simple with NACA 2412 or 4412. Proven airfoils with well-known characteristics. Used for years in a variety of Cessnas and other aircraft. I haven't had a chance to find the stats for these airfoils so we can compare them to the Pietenpol FC-10. Anyone know where to find this information online? Ken ________________________________ Message 16 ____________________________________ Time: 05:49:37 PM PST US From: "hjarrett" Subject: Re: Pietenpol-List: More new pictures from 40-yr-old Piet Got to start looking at the whole stack of messages before I reply. Cute kid. Can he fly yet? Hank J ----- Original Message ----- From: hjarrett To: pietenpol-list@matronics.com Sent: Monday, January 26, 2004 8:15 PM Subject: Re: Pietenpol-List: More new pictures from 40-yr-old Piet The blue hue is usually from fluorescent lights. Incandescent lights will make the pictures a little yellow. Most people don't even notice, you must be picky or have really good color perception. By the way why is there an ear in the top right instrument hole? Is that the audio control? Hank J ----- Original Message ----- From: BARNSTMR@aol.com To: pietenpol-list@matronics.com Sent: Sunday, January 25, 2004 11:19 PM Subject: Pietenpol-List: More new pictures from 40-yr-old Piet Howdy all from Texas. Finally got a chance to work some more this weekend on the Piet. Also, added a few pics to the link below to fill in the progress made in the past few months.... slow but sure. http://www.mykitplane.com/Planes/photoGalleryList2.cfm?AlbumID188 Im not sure why, but all the pics have a blue hue to them. Makes us look like smurfs. Anysay, notice the spring gear re-build job done by my partner Lon Carr back in October. We are now very happy with a straight and true gear. The detail design of this gear is part Piet and part Hatz CB1. Today, I finally swallowed hard and got out that mean old fly-cutter and bored all the instrument holes in the rear panel. Had to do it on the ship since it was already permanently glued and nailed in place by the previous builder. Man that fly-cutter worked GREAT. Keys to a good job... 1) start with a sharp cutter tool. 2) keep a firm grip (used 14V Dewalt cordless drill) 3) keep a square alignment to the workpiece 4) don't cut slow...go ahead and cut fast enough to mell the smoke. 5) use a backing board (clamped) to prevent the farside last ply from tearing away. 6) Be safe. Use a removed front bezel from an old instrument as a drill guide for perfect alignment. Had a great weekend teaching my 9 yr-old stepson some sheet metal fabrication techniques. We built some channel stiffeners to bridge between the rear instrument and the front pit headrest. Also the ones forward of the front instrument panel. Added #8 nut plates for anchoring the cockpit cowlings. See also the attached pic. Those instruments really add some life. Since the original panel has some old stains from nails we have purchased some sticky-back wood veneer, which we will use to finish out the panel. Its getting closer...just slow. All the best. Terry Bowden ph (254) 715-4773 fax (254) 853-3805 ________________________________ Message 17 ____________________________________ Time: 05:54:50 PM PST US From: "dpaul" Subject: Pietenpol-List: Front Seat Support List, Does the V shaped brace serve any purpose other than supporting the back of the front seat? For those of us with long legs that "brace" is in the way....and the plywood too. I would like to eliminate the V shape and just install vertical wood or metal seat back supports. A narrow seat back for the front passenger shouldn't be any big deal....right? My knees go practically all the way to the top of the fuse so I would like to find a way to delete the V. Thanks, Dave in Missouri ________________________________ Message 18 ____________________________________ Time: 06:21:14 PM PST US From: "Greg Cardinal" Subject: Re: Pietenpol-List: Front Seat Support The seat backs act as BIG gussets to keep the fuselage square. The V-shaped brackets brace the plywood and prevent it from buckling. Greg Cardinal ----- Original Message ----- From: dpaul To: pietenpol-list@matronics.com Sent: Monday, January 26, 2004 10:01 PM Subject: Pietenpol-List: Front Seat Support List, Does the V shaped brace serve any purpose other than supporting the back of the front seat? For those of us with long legs that "brace" is in the way....and the plywood too. I would like to eliminate the V shape and just install vertical wood or metal seat back supports. A narrow seat back for the front passenger shouldn't be any big deal....right? My knees go practically all the way to the top of the fuse so I would like to find a way to delete the V. Thanks, Dave in Missouri ________________________________ Message 19 ____________________________________ Time: 07:24:19 PM PST US From: "Alex Sloan" Subject: Re: Pietenpol-List: corvair conversion cost Tom, I have a minimum in my Corvair. I paid about $40.00 for it. I bought forged pistons, about $350.00, had crank ground and pistons honed, about $150.00, New rings, from Clark's, you can call them at 413-625-9776 and order their catalog and check all their prices. New oil pump, from Clark's, Exhaust valves, valve springs & valve seals , all from Clark's, larger oil cooler from Clark's, New John Deere alternator and regulator, $345.00, new rod bolts, do not remember what they were but not from Clark's, welded up the engine mount my self, and most importantly, William Wynn's Corvair overhaul manual as well as Richard Finks book on Corvair engines. I can not give you a total, as I have done it piecemeal and I promise you, it is a lot less than a Lycoming or Continental. Oh yes, bought the prop hub and puck from William Wynn. You can go to his web link and check his prices. Bearings for the crank, about $350.00. J.C. Whitney would have been less but I had the man who did the crank and cylinders order them so I would be sure to get the correct size. Oh yes, a new OT-10 cam shaft from Clark's. Ordered 6061-T6 1/8 inch piece of aluminum from Aircraft Spruce to make the top cover for the engine. New valve rockers from Corvair underground, I think. You can take the Clark's catalog and price list and piece together about what you can spend. I spent a lot less than some but probably about average for most. Alex Sloan Florence, Alabama. ----- Original Message ----- From: Brants To: pietenpol-list@matronics.com Sent: Sunday, January 25, 2004 8:03 PM Subject: Pietenpol-List: corvair conversion cost Anyone out there willing to share what money they have into their corvair conversion? Just trying to get a rough idea so I can channel my limetted building funds appropriately. Thanks, Tom Brant Brooklyn Park, MN ________________________________ Message 20 ____________________________________ Time: 07:37:31 PM PST US From: "Alex Sloan" Subject: Re: Pietenpol-List: corvair conversion cost Tom, I also had the man who ground the crank thread the crank for the safety shaft and I bought the safety shaft from William Wynne. Was not that much and you can check William's price on his web site. Alex Sloan ----- Original Message ----- From: Brants To: pietenpol-list@matronics.com Sent: Sunday, January 25, 2004 8:03 PM Subject: Pietenpol-List: corvair conversion cost Anyone out there willing to share what money they have into their corvair conversion? Just trying to get a rough idea so I can channel my limetted building funds appropriately. Thanks, Tom Brant Brooklyn Park, MN ________________________________ Message 21 ____________________________________ Time: 07:37:44 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: Rib jig --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 1/26/04 12:21:49 AM Central Standard Time, BARNSTMR@aol.com writes: << Chuck... Cool Pic. Are you using that rib to mark off your transcontinental Piet course for next summer? >> That's right, Terry !! I actually have the course marked out with a highlighter, but you can't see it. The pictures that you sent, as well as the one that Max sent, I could not view them. It took a lot of time, acting like it was downloading something, but nada...nothing. I did, however, view the one I sent to the group (rib & U.S. chart - jpg format). The other thing different about the one you & Max sent, was that in the 'sender' it included the '@aol.com', which it never did before, because I'm on aol. Chuck G. do not archive ________________________________ Message 22 ____________________________________ Time: 07:39:45 PM PST US From: "John Dilatush" Subject: Re: Pietenpol-List: Re: Tail Volume --> Pietenpol-List message posted by: "John Dilatush" ----- Original Message ----- From: "Christian Bobka" Subject: Re: Pietenpol-List: Re: Tail Volume ================================== Chris, I am wrong and you are right! When I checked my references I wasn't careful enough, and thought that in an undercambered airfoil the CP was actually ahead of the AC. When I called my friend, I evidently didn't phrase my question clearly and asked if it could be possible that the CP on a heavily undercambered airfoil could move with increasing angle of attack foward of the AC. I wasn't listening when he agreed that under some circumstances this could happen, so I just jumped to the conclusion that this was a normal pattern. Sorry for the confusion. John =============================== > --> Pietenpol-List message posted by: "Christian Bobka" > > John, > > From "Simple Aerodynamics" by Charles Monteith, April 1924, a text book used > at West Point, page 72 says, > > "When an airfoil is at the angle of attack of zero lift, there is a download > on the front part of the airfoil and an up load on the rear portion, which > manifests itself as a negative or diving moment." > > On the undercambered RAF-15 airfoil, the CP in % of chord plot is as > follows: > > AOA CP > 0 49 > 2 38 > 4 34 > 6 31 > 8 30 > 10 29 > 12 30 > 14 34 > > This is a very shallow CP plot meaning that there is small shift in the CP > with changes in AOA > > As long as the CG is forward of the CP, ignoring a few other unimportant to > this discussion factors, it is obvious that the lifting forces are summed > behind the CG. This would couse the nose to go down "which manifests itself > as a negative or diving moment." > > The RAF 15 displays the characteristic movement of the CP forward as the a > higher and higher AOA is achieved getting as far forward as 29% of chord at > 10 degrees AOA. > > In comparison, the USA-35B, which is used on the J-3 Cub, has the following > CP v AOA plot: > > AOA CP in % of chord > -4 120 > -3 70 > -2 60 > 0 45 > 2 40 > 4 36 > 6 34 > 8 33 > 10 32 > 12 31 > 14 30 > 16 30.5 > > This is a very steep plot at the beginning meaing that as AOA decreases, the > CP moves way aft. As a matter of fact the plot I looked at shows the CP to > be 20% behind the wing trailing edge at a -4 degree AOA! That is a negative > pitching moment for you! > > I partially agree with your buddy. The pitching moment appears to be less > traveled with the undercambered airfoil. But nose down is negative! > > Chris > > > ----- Original Message ----- > From: "John Dilatush" > To: > Sent: Monday, January 26, 2004 11:17 AM > Subject: Re: Pietenpol-List: Re: Tail Volume > > > > > > --> Pietenpol-List message posted by: "John Dilatush" > > > > > > ----- Original Message ----- > > From: "Christian Bobka" > > To: > > Sent: Saturday, January 24, 2004 3:35 PM > > Subject: Re: Pietenpol-List: Re: Tail Volume > > > > > > > --> Pietenpol-List message posted by: "Christian Bobka" > > > > =============================== > > Chuck and Chris, > > > > My research. and then after also consulting with a good friend who is an > > aeronautical engineer confirmed my impression that an undercambered > airfoil > > is not likely to have a downward pitching moment. > > > > As defined in the books, a negative pitching moment is a moment which > forces > > the leading edge of an airfoil UPWARD with increasing angles of attack not > > down as you imply. > > > > This then, doesn't appear to be the answer for the rearward CG that the > > Pietenpol uses. > > > > Not trying to be a smart ass, just trying to correct a misconception of > > terms. > > > > John > > ==================================== > > > Chuck, > > > > > > Excellent observation. I have no data on the Navion but will look > later. > > > The Type Certificate Data Sheets are available on the FAA website. > > > > > > Chris > > > ----- Original Message ----- > > > From: > > > To: > > > Sent: Saturday, January 24, 2004 4:03 PM > > > Subject: Re: Pietenpol-List: Re: Tail Volume > > > > > > > > > > > > > > --> Pietenpol-List message posted by: Rcaprd@aol.com > > > > > > > > In a message dated 1/24/04 11:22:51 AM Central Standard Time, > > > > bobka@compuserve.com writes: > > > > > > > > << So the piet's airfoil must fall somewhere between what is common > > today > > > and > > > > a zero pitching moment airfoil. > > > > >> > > > > > > > > The Pietenpol, as well as any undercambered airfoil, has a lot of > > negative > > > > pitching moment (nose down). I believe this is why the Piet is > somewhat > > > > tolorant of an aft C.G. That's the thing I've always been curious > > about, > > > is why > > > > Pietenpols are more forgiving for an aft C.G. condition. B.H.P called > > out > > > 1/3 > > > > (33.3%) of the chord, as the aft limit. I've never seen, or heard of > > any > > > other > > > > plane with the aft C.G. limit that far back. Most designs call out no > > > more > > > > than 30% of the chord for the aft limit, but they are not > undercambered. > > > > (Tailwind calls out 28% as the aft C.G. limit). I think this is > > because > > > an > > > > undercambered airfoil has such a high negative pitching moment, that > it > > is > > > more > > > > forgiving of an aft C.G. I've tried unsuccessfully to find the aft > C.G. > > > limit of > > > > planes like the Jenny, but it is a Biplane - difficult to compare. > > > Another > > > > design that has an undercambered airfoil is the Ryan Navion. Does > > anyone > > > have the > > > > C.G. range of the Ryan Navion, or any other plane that has an > > > undercambered > > > > airfoil ? > > > > > > > > Chuck Gantzer > > > > NX770CG > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > ________________________________ Message 23 ____________________________________ Time: 07:48:57 PM PST US From: "Alex Sloan" Subject: Re: Pietenpol-List: dead soft stainless and aluminum --> Pietenpol-List message posted by: "Alex Sloan" Mike, Thanks a lot. I will call mr Vogelsong. Alex Sloan ----- Original Message ----- From: "Michael D Cuy" Subject: Pietenpol-List: dead soft stainless and aluminum > --> Pietenpol-List message posted by: Michael D Cuy > > Alex & group, > > I think the designation for dead soft is 000, but am not positive. I made > my cooling eyebrow/baffles like Frank P. did using .025" dead soft aluminum > and the firewall from the same but in stainless. Got both from Dillsburg > Aeroplane Works, in PA. 717-432-4589. > > Mike > > ________________________________ Message 24 ____________________________________ Time: 08:12:19 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: more airfoil talk --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 1/26/04 9:09:36 AM Central Standard Time, kchambers@winternals.com writes: << I haven't had a chance to find the stats for these airfoils so we can compare them to the Pietenpol FC-10. Anyone know where to find this information online? >> Ken, Where did you come up with the 'Pietenpol FC-10 ? The story goes...B.H.P. drew up the airfoil on the hanger floor. Original design. Chuck G. ________________________________ Message 25 ____________________________________ Time: 08:15:29 PM PST US From: "Alex Sloan" Subject: Re: Pietenpol-List: Rib jig --> Pietenpol-List message posted by: "Alex Sloan" Chuck, Thanks for the rib building description. Great ideas for us first time wood builders. Great info. Alex Sloan ----- Original Message ----- From: Subject: Re: Pietenpol-List: Rib jig > Deon, > I'm going to try the picture thing. This is my first try with this new > fangled digital camera, so let me know if it turns out. > As Max pointed out, the outside perimiter of all the ribs must be > identical. From the looks of your rib jig, it doesn't appear you have these supports > installed yet. Make sure the capstrips contact these blocks, with some type > of blocking from the opposite side. Max used a cam lobe, which is the method > I used when I built the ribs for my Tailwind, and it works really well. It > compensates for variations in the thickness (1/4") of the capstrips. The other > dimension that you have to pay particular attention to, is the dimension > between the spars. The plans call out 27 3/4" between the spars. If you cut a > piece of scrap wood to the dimensions of the spars, (1" X 4 3/4") then install > these blocks where the spars go. Make these blocks about 5/8" or 3/4" long, so > they stick up higher than the capstrips, and you can install the gussets up > against it, and maintain identical placements of the gussets. An actual piece > of the spar itself would be even better, if you already have the spars, and > you can afford to cut a couple of pieces off the end of the spar. Just make > sure your spars are long enough, beforehand. > I think the gussets you have marked out on your paper, between the spars, > could be just a little bit longer. I made mine 1 3/4" X 1". I see you > haven't yet drawn in the one on the top. > A small problem I had when I was building my ribs, was that the 1/2" > dimension varied in the capstrips, and some of the upright sticks wasn't quite > flush with the top & bottom cap strips, where the gussets go. I made small > sanding blocks, with sticky back 100 grit sand paper, and plane down the area where > the gussets go, so it was flush. Be sure to remove all dust, before you glue > the gussets on with T88 adhesive. You could use wax paper, or some type of > package tape on the places you don't want the adhesive to stick. > After the adhesive has thoroughly cured, and you carefully pop the rib > out of the jig, flip it over to install the gussets on the other side. Rough up > the area a little bit because it will be as smooth as the non stick surface, > where the epoxy runs down. Install new pieces in the jig, so you can use the > same batch of adhesive for both opporations. You'll eventually figure out how > big a batch you need. Don't use wax coated cups to mix epoxy. When you > have extra epoxy left over, make a destructive test piece, with scraps. > I numbered (with a pencil, where there wasn't going to be any adhesive), > and cut all the cap strip lengths, and gussets, after I built my second rib. > It's a slow process to complete a ship set of ribs, but it is an enjoyable > opporation. A rib a day. > It's a good idea to build two extra ribs, one for destructive tests, and > one to proudly hang on your wall !! This also gives you the opportunity to > select the best ones for the wing. > When you're all done with the ribs, you've earned the right to do the > dance called the 'Rib Jig' !!! > > Chuck Gantzer > Wichita KS > NX770CG > ---- ________________________________ Message 26 ____________________________________ Time: 08:18:31 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: more airfoil talk --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 1/26/04 10:01:51 AM Central Standard Time, Isablcorky@aol.com writes: << It's high lift and less drag than the FC-10. >> Corky, Do you know where the FC-10 came from ? Chuck G. ________________________________ Message 27 ____________________________________ Time: 08:27:45 PM PST US From: "Jim Markle" Subject: Pietenpol-List: maybe where the FC-10 came from........ --> Pietenpol-List message posted by: "Jim Markle" Chuck asked: > Corky, > Do you know where the FC-10 came from ? > > Chuck G. > Here's one possibility: -----Original Message----- From: DJ Vegh [mailto:aircamper@imagedv.com] Subject: Re: Pietenpol-List: Airfoil ummm... not true... the GN-1 has the same airfoil as the Piet, with the exception of a slightly more blunt leading edge. The GN-1 and Piet's are not Clark Y. Bernie called it a FC-10. why?? he used a French Curve to draw it and it took him about 10 minutes.... I forget where I read that but thought it comical.... DJ Vegh N74DV www.raptoronline.com Mesa, AZ ________________________________ Message 28 ____________________________________ Time: 08:31:30 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: corvair conversion cost --> Pietenpol-List message posted by: Rcaprd@aol.com DJ, I've added that to your 'Infomation List'. Chuck G. ________________________________ Message 29 ____________________________________ Time: 08:53:31 PM PST US From: Richard Schreiber Subject: Pietenpol-List: PLYWOOD REQUIREMENTS --> Pietenpol-List message posted by: Richard Schreiber I'm getting ready to start building my fuselage (long version) and I was wondering if anyone remembers what size sheets of plywood they had to buy? Thanks, Rick Schreiber ________________________________ Message 30 ____________________________________ Time: 08:55:15 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: Re: Tail Volume --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 1/26/04 11:19:25 AM Central Standard Time, dilatush@amigo.net writes: << My research. and then after also consulting with a good friend who is an aeronautical engineer confirmed my impression that an undercambered airfoil is not likely to have a downward pitching moment. As defined in the books, a negative pitching moment is a moment which forces the leading edge of an airfoil UPWARD with increasing angles of attack not down as you imply. >> John et all, I got a lot of my info from a friend that has done lots of research on airfoils, and has all the expensive software to design his own, which he has done. His name is Mike Schuck. He's not a Piet builder, but has lots of interest and experience in evaluating airfoils. He explained to me that a negative pitching moment, is a nose down condition. Let's look at the wing by itself in a wind tunnel. Think about it...at zero degrees angle of attack (AOA) and undercambered airfoil will certainly pitch nose down. Flat bottom airfoil will pitch down some, and a symmetrical airfoil has NO pitching moment. Some laminar flow airfoils, that are somewhat semi-symmetrical, have the trailing edge reflexed up a little, to counteract the negative pitching moment, therefore using a smaller horizontal stab. I'm still maintaining the opinion that the undercambered airfoil of the Piet is the reason it is somewhat tolerant of an aft C.G. condition. Chuck Gantzer ________________________________ Message 31 ____________________________________ Time: 09:26:02 PM PST US From: "Deon Engelmann" Subject: RE: Pietenpol-List: Rib jig 2 Hi Got my own message back and found that I attached the wrong pics. Here are the correct ones. Deon Engelmann EAA322 Midrand # SA12055 Pretoria South Africa ________________________________ Message 32 ____________________________________ Time: 09:50:53 PM PST US From: "Mike Whaley" Subject: Pietenpol-List: Seeking Piet ride at Sun N Fun --> Pietenpol-List message posted by: "Mike Whaley" Hi, I would like to ask (OK, shamelessly beg, plead, and whine...) for a ride in a Piet at Sun 'N Fun, if anyone out there is interested. I plan to build one (Corvair, 3-pc. wing, long fuse, rocket launchers...) starting sometime this year. Gotta find a house with a garage first, you know the story... anyway, I'm not yet a pilot but will be working on that soon as well. I've been slowly amassing Piet and Corvair knowledge for a while but haven't yet had the chance to actually fly in one, so would love a "formal" introduction to the type. There would be a hamburger in it for you or something along those lines, so long as that wouldn't upset the FAA (I guess so long as it didn't cost more than the fuel and oil then it's OK, right? ) I'll be in the Steen Aero Lab tent during SNF, you all please stop in and say hi. Anyway, if anyone out there would like to get together and show off their pride and joy, please email me privately. Thanks! -Mike Mike Whaley merlin@ov-10bronco.net Webmaster, OV-10 Bronco Association http://www.ov-10bronco.net/ http://www.ov-10bronco.net/users/merlin/ ________________________________ Message 33 ____________________________________ Time: 10:22:23 PM PST US From: "Catdesign" Subject: Re: Pietenpol-List: PLYWOOD REQUIREMENTS --> Pietenpol-List message posted by: "Catdesign" One 4'x8' sheet for the sides and one 2'x8' (half sheet) of 1/4" for the floor. If you build the fuselage sides very carefully you can get the sides out of one sheet and still have some extra to trim off flush with the bottom ply. Don't just cut it down the middle and hope it works. Try to trace the outline of your fuselage on the full sheet before cutting. Also make sure your fuse is just slightly under 24" wide, the ply is usually cut 1/2 blade width shy of 24". Chris T. Sacramento, Ca ----- Original Message ----- From: "Richard Schreiber" Subject: Pietenpol-List: PLYWOOD REQUIREMENTS > --> Pietenpol-List message posted by: Richard Schreiber > > I'm getting ready to start building my fuselage (long version) and I was > wondering if anyone remembers what size sheets of plywood they had to buy? > > Thanks, > > Rick Schreiber > > ________________________________ Message 34 ____________________________________ Time: 10:26:27 PM PST US From: "Catdesign" Subject: Re: Pietenpol-List: Front Seat Support Dave just how tall are you? I am 6'-1" and I fit fine. I cut the knee holes a bit higher and have no problem with the "V" braces. I also put the seat in as low as it could go. I would not leave out the braces. If it really is a problem maybe you could laminate up some curved braces or something. Chris T. Sacramento, Ca ----- Original Message ----- From: dpaul To: pietenpol-list@matronics.com Sent: Monday, January 26, 2004 8:01 PM Subject: Pietenpol-List: Front Seat Support List, Does the V shaped brace serve any purpose other than supporting the back of the front seat? For those of us with long legs that "brace" is in the way....and the plywood too. I would like to eliminate the V shape and just install vertical wood or metal seat back supports. A narrow seat back for the front passenger shouldn't be any big deal....right? My knees go practically all the way to the top of the fuse so I would like to find a way to delete the V. Thanks, Dave in Missouri ________________________________ Message 35 ____________________________________ Time: 11:26:50 PM PST US From: Rcaprd@aol.com Subject: Re: Pietenpol-List: Rib jig 2 --> Pietenpol-List message posted by: Rcaprd@aol.com Deon, Your rib jig is lookin' good !! Triple check the dimensions between the spars, and make sure they are parallel to each other, before you install the spar blocks. Triple check all the dimensions up from the datum line, and all along the outside dimension lines, while you have your first capstrip in the jig, and adjust accordingly. Sometimes ya just gotta split the difference. On my Pietenpol rib jig, when installing the gussets, I used weight to hold them till cured, after the epoxy was spread. Instead of using stables or nails, I used every 1/2" socket I had, as well as anything that weighed about 10 ounces, on top of each gusset. That was quit a bit of weight on the table, with two ribs (one flipped over). On my Tailwind rib jig, I made clamps and wing nuts to hold the gussets during cure. It took a bit longer to build, though. Spread a thin coat of epoxy to the entire side of the gusset where it contacts, as well as on the surfaces of the cap strips where it is between the gussets. This will eliminate the necessity of the tedious job of using a small brush to dab varnish up in there between the gussets, when you are to the varnish stage (after the wing is 100% complete). Leave the forward, and aft ends of the capstrips hang over, and cut them off after the rib has gussets on both sides. It's best to cut them off after you have a ship set of ribs built, so you can do that operation at the same time. Then slide and stack all of ribs together on to the spars, and sand and plane the forward and aft ends of the ribs all the same final length. Max used a method of popping the rib out of the jib, after epoxy cure, that uses a dowel pin, up through a hole, located under each gusset location. I used a thin blade to carefully pop each location out. If you have some problem popping the rib out of the jig, after you've built a few ribs, you could always drill a hole in the rib jig at the gusset locations, and use Max's method. Chuck Gantzer NX770CG NorEaster blew in today...Cold day in Kansas