Original Posted By: "John Dilatush"
Hi everyone. This is my first posting to this list (although Ive been lurking for a while) and I have a situation that I would really appreciate any comments or suggestions on.While at Oshkosh this year, a very good friend of mine, who has too many airplanes in various stages of repair, offered to give me a Piet project that he had acquired several years ago from a friend of his (the builder). I picked up the project this past weekend and it consists of a completed fuselage structure with the plywood skin on the forward half and the floor, a complete set of wing ribs, and a complete set of tail surfaces.The workmanship on the project looks to be acceptable however, one thing that bothered me was the longerons and the other fuselage members appeared to be small in cross-section. The builder happened to stop by while we were loading it all onto my trailer. He said that he had used douglas fir and since his research proved to him that fir was 25% stronger than spruce, he had reduced the dimensions of the members by 25% (from 1" to 3/4"). The problem with this line of thinking, as I see it, is that when you multiply 3/4" by 3/4" you end up with 0.56 square inches as the cross-sectional area of the wood that was used, as compared to 1.00 square inch in a 1" x 1" member. That means the longerons in my fuselage actually contain 44% less material than had they been built using 1x1 stock.I would sincerely appreciate any thoughts you all might have as to the usability of this fuselage. I should say that it "feels" strong and I did sit in it while it was supported at the approximate landing gear points and there appeared to be no deflection or creaking at all (there were a few engine noises made however). I also wonder if I might be able to epoxy some 1/4" strips to the various members for added strength? The builder said he had used West System epoxy to construct it.Thanks for your input.Concerned that messages may bounce because your Hotmail account is over ________________________________________________________________________________
Pietenpol-List: Good Fuselage??
Re: Pietenpol-List: Good Fuselage??
Original Posted By: "Eric Williams"
----- Original Message -----
----- Original Message -----
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Pietenpol-List: Good Fuselage??
Original Posted By: "John Ford"
Re: Pietenpol-List: Good Fuselage??
Original Posted By: Hubbard, Eugene
for point of reference.... my dad's Fisher Celebrity (open cockpit biplane) ismade from 5/8 sq. spruce longerons. Design/Construction methods are very similarto a Piet. His plane has a gross wt. of about 1100lb and is stressed to+4 -2 as I recall.My initial thoughts are that your Piet will be strong enough, although I'd keepthe power to something like 65-85hp.DJ----- Original Message -----
for point of reference.... my dad's Fisher Celebrity (open cockpit biplane) ismade from 5/8 sq. spruce longerons. Design/Construction methods are very similarto a Piet. His plane has a gross wt. of about 1100lb and is stressed to+4 -2 as I recall.My initial thoughts are that your Piet will be strong enough, although I'd keepthe power to something like 65-85hp.DJ----- Original Message -----
Re: Pietenpol-List: Good Fuselage??
Original Posted By: BARNSTMR(at)aol.com
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Re: Pietenpol-List:
Original Posted By: "Douwe Blumberg"
I don't think it would run hotter. There is no more power in high octanefuel than low octane fuel.walt evansNX140DL----- Original Message -----
I don't think it would run hotter. There is no more power in high octanefuel than low octane fuel.walt evansNX140DL----- Original Message -----
Re: Pietenpol-List:
Original Posted By: "w b evans"
But there is a lot more lead in 100 LL than there is in auto fuel.... Withlow compression like the Model A has, it could lead to plug fouling and/orsticky valves..We used to add TCP from Alcor to eliminate these issues but we can't seem tofind it anymore.......Fred----- Original Message -----
But there is a lot more lead in 100 LL than there is in auto fuel.... Withlow compression like the Model A has, it could lead to plug fouling and/orsticky valves..We used to add TCP from Alcor to eliminate these issues but we can't seem tofind it anymore.......Fred----- Original Message -----
> Pietenpol-List:
Original Posted By: del magsam
Re: Pietenpol-List: Good Fuselage??
Original Posted By: "Eric Williams"
I have heard many good suggestions but how about just doing a proof loadtest on it? You have nothing to loose if it breaks (you wouldn't havewanted to fly it anyway if it fails and it will burn easier in smallerpieces). If it passes a proof load you know it is safe and the rest of thegroup has more than flapping lips to show that the original design was "overdesigned" (which I personally do believe). Even with a detailed stressanalysis I wouldn't fly it without a proof load anyway.Hank Jarrett----- Original Message -----
I have heard many good suggestions but how about just doing a proof loadtest on it? You have nothing to loose if it breaks (you wouldn't havewanted to fly it anyway if it fails and it will burn easier in smallerpieces). If it passes a proof load you know it is safe and the rest of thegroup has more than flapping lips to show that the original design was "overdesigned" (which I personally do believe). Even with a detailed stressanalysis I wouldn't fly it without a proof load anyway.Hank Jarrett----- Original Message -----
Re: Pietenpol-List:
Original Posted By: "w b evans"
High octane fuel actually has LESS energy than low octane fuel. It alsoburns SLOWER. The whole point of increasing the octane level is to stopdetonation and control the burn in the combustion chamber. This allowshigher compression ratios which lets you pack more air and fuel in eachchamber and THAT gives you more power. There are more pounds of lessefficient fuel being burned so you get less HP per pound but get more totalpower by burning more fuel. If you try and use low octane fuel in a highcompression engine it will knock itself apart. If you use fuel with highlead in a low compression engine the lead can't blow out the exhaust anddeposits in the combustion chamber. ALWAYS use the fuel your engine isdesigned for or learn to live with the problems (engines destroyed bydetonation or lead fouling).Hank Jarrett----- Original Message -----
High octane fuel actually has LESS energy than low octane fuel. It alsoburns SLOWER. The whole point of increasing the octane level is to stopdetonation and control the burn in the combustion chamber. This allowshigher compression ratios which lets you pack more air and fuel in eachchamber and THAT gives you more power. There are more pounds of lessefficient fuel being burned so you get less HP per pound but get more totalpower by burning more fuel. If you try and use low octane fuel in a highcompression engine it will knock itself apart. If you use fuel with highlead in a low compression engine the lead can't blow out the exhaust anddeposits in the combustion chamber. ALWAYS use the fuel your engine isdesigned for or learn to live with the problems (engines destroyed bydetonation or lead fouling).Hank Jarrett----- Original Message -----
Re: Pietenpol-List: Good Fuselage??
Original Posted By:
It seems to me I recall Bill Rewey telling me he made his with 3/4" sq.longerons. You can give him a call at 608-833-5839 and verify this. He hasbeen flying for a number of years.Alex Sloan----- Original Message -----
It seems to me I recall Bill Rewey telling me he made his with 3/4" sq.longerons. You can give him a call at 608-833-5839 and verify this. He hasbeen flying for a number of years.Alex Sloan----- Original Message -----
Re: Pietenpol-List: Good Fuselage??
Original Posted By: Clif Dawson
I want to say that I really appreciate all the opinions and suggestions you guys have given on this topic. Honestly there have been some really good, thoughtful ideas here. I think I'm going to print them all out and make them a permanent part of my official builders log. After considering what you all have said, and listening to my own gut feelings, I think I will probably end up building a new fuselage. I think laminating strips to the longerons to bring up the dimension would work if it could be done in one long continuous piece. The problem there is that many of the gussets and cross braces would be in the way and would have to be removed to allow for one nice long strip to be added. At that point we're into disassembling this fuse and I see that getting messy.Also, this one is the short version and was built following the original Flying and Glider manual plans which gives it some different dimensions and curvatures. I would prefer to build the long version and for it to follow exactly the more up to date plans so I'm not trying to mix two sets of dimensions together at some point.Lastly, this is one of those big "lifetime" projects that I really want to feel good about and have confidence in. I would hate to go through the whole building process and be afraid to fly it. As soon as I started describing to my wife how I might be able to salvage it with all these extra pieces glued in here and there, she reminded me that I've been down this road before with other projects and I always end up saying "I wish I had just done it the right way from the beginning".But still, even with all that said... there's a completed fuselage in my garage... and man it bugs me not to use it. I guess I'd better get busy and build the next one so I can quit whining about it.Again, thanks for the help guys.EricMSN Shopping upgraded for the holidays! Snappier product search... http://shopping.msn.com________________________________________________________________________________Date: Thu, 13 Nov 2003 00:25:45 -0800
I want to say that I really appreciate all the opinions and suggestions you guys have given on this topic. Honestly there have been some really good, thoughtful ideas here. I think I'm going to print them all out and make them a permanent part of my official builders log. After considering what you all have said, and listening to my own gut feelings, I think I will probably end up building a new fuselage. I think laminating strips to the longerons to bring up the dimension would work if it could be done in one long continuous piece. The problem there is that many of the gussets and cross braces would be in the way and would have to be removed to allow for one nice long strip to be added. At that point we're into disassembling this fuse and I see that getting messy.Also, this one is the short version and was built following the original Flying and Glider manual plans which gives it some different dimensions and curvatures. I would prefer to build the long version and for it to follow exactly the more up to date plans so I'm not trying to mix two sets of dimensions together at some point.Lastly, this is one of those big "lifetime" projects that I really want to feel good about and have confidence in. I would hate to go through the whole building process and be afraid to fly it. As soon as I started describing to my wife how I might be able to salvage it with all these extra pieces glued in here and there, she reminded me that I've been down this road before with other projects and I always end up saying "I wish I had just done it the right way from the beginning".But still, even with all that said... there's a completed fuselage in my garage... and man it bugs me not to use it. I guess I'd better get busy and build the next one so I can quit whining about it.Again, thanks for the help guys.EricMSN Shopping upgraded for the holidays! Snappier product search... http://shopping.msn.com________________________________________________________________________________Date: Thu, 13 Nov 2003 00:25:45 -0800
RE: Pietenpol-List: Good Fuselage??
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Eric I agree with Gene Hubbard and Jim Ash on this fuselage. A couple ofpoints that haven't been made (or I missed reading them) is that unlike mosttruss fuselages, the Piet has no interbay diagonal bracing - there are nodiagonals running in the plane parallel to the firewall, which resisttorsion in the fuselage. On mine I added small corner blocks at all thevertical and horizontal members to add a little bit of torsional stiffness ,but most of the torsional rigidity of the fuselage actually comes from thetorsional stiffness of the longerons themselves. Using such thin longeronsmake make the fuselage very springy in torsion, which might produce someunpleasant effects rolling into and out of turns, or in turbulance.One other point that I don't think has been mentioned is that building thefuselage is one of the more rewarding parts of building a Pietenpol, and isnot difficult.Good luck with your decision.Jack PhillipsNX899JP - getting the last finishing tapes on the fuselage this weekend,then heading for the paint booth. -----Original Message-----
Eric I agree with Gene Hubbard and Jim Ash on this fuselage. A couple ofpoints that haven't been made (or I missed reading them) is that unlike mosttruss fuselages, the Piet has no interbay diagonal bracing - there are nodiagonals running in the plane parallel to the firewall, which resisttorsion in the fuselage. On mine I added small corner blocks at all thevertical and horizontal members to add a little bit of torsional stiffness ,but most of the torsional rigidity of the fuselage actually comes from thetorsional stiffness of the longerons themselves. Using such thin longeronsmake make the fuselage very springy in torsion, which might produce someunpleasant effects rolling into and out of turns, or in turbulance.One other point that I don't think has been mentioned is that building thefuselage is one of the more rewarding parts of building a Pietenpol, and isnot difficult.Good luck with your decision.Jack PhillipsNX899JP - getting the last finishing tapes on the fuselage this weekend,then heading for the paint booth. -----Original Message-----
Pietenpol-List: Good Fuselage??
Original Posted By: "Sayre, William G"
Re: Pietenpol-List: Good Fuselage??
Original Posted By: Isablcorky(at)aol.com
Subject: Re: Pietenpol-List: Good Fuselage??Jack, the fuselage plans call for spruce wedges at the corners of the fuselage vertical and diagonal struts. You did more than this?Rick HollandOn mine I added small corner blocks at all thevertical and horizontal members to add a little bit of torsional stiffness ,but most of the torsional rigidity of the fuselage actually comes from thetorsional stiffness of the longerons themselves. ________________________________________________________________________________
Subject: Re: Pietenpol-List: Good Fuselage??Jack, the fuselage plans call for spruce wedges at the corners of the fuselage vertical and diagonal struts. You did more than this?Rick HollandOn mine I added small corner blocks at all thevertical and horizontal members to add a little bit of torsional stiffness ,but most of the torsional rigidity of the fuselage actually comes from thetorsional stiffness of the longerons themselves. ________________________________________________________________________________
RE: Pietenpol-List: Good Fuselage??
Original Posted By: "Ed Grentzer"
Jack,If what you are talking about is the same as what I call "match boxing"? Ithink the pilots seat back and the firewall help stop this action.Skip,In Atlanta where Harry Hooper and I just trued my spoke wheels and mountedthe tires.The spokes were a lot easier than I thought, the tires a lot harder.> the Piet has no interbay diagonal bracing - there are no diagonals runningin the plane >parallel to the firewall, which resist>torsion in the fuselage. >Jack Phillips________________________________________________________________________________
Jack,If what you are talking about is the same as what I call "match boxing"? Ithink the pilots seat back and the firewall help stop this action.Skip,In Atlanta where Harry Hooper and I just trued my spoke wheels and mountedthe tires.The spokes were a lot easier than I thought, the tires a lot harder.> the Piet has no interbay diagonal bracing - there are no diagonals runningin the plane >parallel to the firewall, which resist>torsion in the fuselage. >Jack Phillips________________________________________________________________________________
> Re: Pietenpol-List: Good Fuselage??
Original Posted By: "John Dilatush"
I always thought that the tortional stiffness of the Piet fuselage came from the diagonal struts that run between the longerons and the vertical struts on all four sides of the fuselage and from the plywood "box". In order for the fuselage to twist the diagonals would have to stretch or compress which just is not going to happen. All components should be in tension or compression. I also thought the spruce wedges were used at the struts and diagonals only at the ash crossmembers. But there I go thinking again. I'd say 3/4" fir would probably be ok but I don't think Id bet my Butt on it. Jack's right....building the fuselage is a awesome experience. Good luck with your Piet and welcome. Ed G.>From: At7000ft(at)aol.com>Reply-To: pietenpol-list(at)matronics.com>To: pietenpol-list(at)matronics.com>Subject: Re: Pietenpol-List: Good Fuselage??>Date: Thu, 13 Nov 2003 09:59:30 EST>>>Jack, the fuselage plans call for spruce wedges at the corners of the>fuselage vertical and diagonal struts. You did more than this?>>Rick Holland>On mine I added small corner blocks at all the>vertical and horizontal members to add a little bit of torsional stiffness >,>but most of the torsional rigidity of the fuselage actually comes from the>torsional stiffness of the longerons themselves.>>Frustrated with dial-up? Get high-speed for as low as $26.95. https://broadband.msn.com (Prices may vary by service area.)________________________________________________________________________________
I always thought that the tortional stiffness of the Piet fuselage came from the diagonal struts that run between the longerons and the vertical struts on all four sides of the fuselage and from the plywood "box". In order for the fuselage to twist the diagonals would have to stretch or compress which just is not going to happen. All components should be in tension or compression. I also thought the spruce wedges were used at the struts and diagonals only at the ash crossmembers. But there I go thinking again. I'd say 3/4" fir would probably be ok but I don't think Id bet my Butt on it. Jack's right....building the fuselage is a awesome experience. Good luck with your Piet and welcome. Ed G.>From: At7000ft(at)aol.com>Reply-To: pietenpol-list(at)matronics.com>To: pietenpol-list(at)matronics.com>Subject: Re: Pietenpol-List: Good Fuselage??>Date: Thu, 13 Nov 2003 09:59:30 EST>>>Jack, the fuselage plans call for spruce wedges at the corners of the>fuselage vertical and diagonal struts. You did more than this?>>Rick Holland>On mine I added small corner blocks at all the>vertical and horizontal members to add a little bit of torsional stiffness >,>but most of the torsional rigidity of the fuselage actually comes from the>torsional stiffness of the longerons themselves.>>Frustrated with dial-up? Get high-speed for as low as $26.95. https://broadband.msn.com (Prices may vary by service area.)________________________________________________________________________________
Pietenpol-List: Re: Good Fuselage??
Original Posted By: Jim Vydra
Eric,My first project, I had completed, I'll say that again, completed a set ofwings for a SuperAce, very similar to a Piet wing; built up ribs, woodenspars. The ribs were the first thing that I had ever built and it dawned onme that I did not FEEL comfortable about their construction. My skills weremoderate at the time and although they may have been OK, the finish wasrough, some pieces were slightly undersized, etc. Not too many months ago,and some may remember me mentioning this, I spent about 30 minutes tearingthe wings apart. I kept the spars and plan on using them as stock for thenext project.The conclusion that I came to was that I could not enjoy flying the plane ifI had a constant concern for the integrity of the aircraft. Immediatelyafter ripping the wings apart and as I stood there looking at the pile, Iknew I had done the right thing.My 2-cents.Robert HainesDu Quoin, Illinois________________________________________________________________________________Date: Fri, 14 Nov 2003 07:11:44 -0800 (PST)
Eric,My first project, I had completed, I'll say that again, completed a set ofwings for a SuperAce, very similar to a Piet wing; built up ribs, woodenspars. The ribs were the first thing that I had ever built and it dawned onme that I did not FEEL comfortable about their construction. My skills weremoderate at the time and although they may have been OK, the finish wasrough, some pieces were slightly undersized, etc. Not too many months ago,and some may remember me mentioning this, I spent about 30 minutes tearingthe wings apart. I kept the spars and plan on using them as stock for thenext project.The conclusion that I came to was that I could not enjoy flying the plane ifI had a constant concern for the integrity of the aircraft. Immediatelyafter ripping the wings apart and as I stood there looking at the pile, Iknew I had done the right thing.My 2-cents.Robert HainesDu Quoin, Illinois________________________________________________________________________________Date: Fri, 14 Nov 2003 07:11:44 -0800 (PST)
Re: Pietenpol-List: Re: Good Fuselage??
Original Posted By: At7000ft(at)aol.com
Re: Pietenpol-List: Re: Good Fuselage??
Original Posted By: Kip & Beth Gardner
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Re: Pietenpol-List: Good Fuselage??
Original Posted By: Michael D Cuy
Subject: Re: Pietenpol-List: Good Fuselage??I say forget the structural analysis and concentrate on the guy who will eventually buy your airplane (maybe from your widow). He needs to be convincedthat the plane is built to known practices. If deviations are taken, a convincingarguement will have to be given to justify the variance from well established practice. The easiest thing to do is build it per the drawings......Carl Vought________________________________________________________________________________Date: Mon, 17 Nov 2003 14:04:08 -0500
Subject: Re: Pietenpol-List: Good Fuselage??I say forget the structural analysis and concentrate on the guy who will eventually buy your airplane (maybe from your widow). He needs to be convincedthat the plane is built to known practices. If deviations are taken, a convincingarguement will have to be given to justify the variance from well established practice. The easiest thing to do is build it per the drawings......Carl Vought________________________________________________________________________________Date: Mon, 17 Nov 2003 14:04:08 -0500
Re: Pietenpol-List: Corvair engine site
Original Posted By: Michael D Cuy
and don't forgetwww.corvaircraft.comDJ----- Original Message -----
and don't forgetwww.corvaircraft.comDJ----- Original Message -----
Re: Pietenpol-List: Good Fuselage??
Original Posted By: Michael D Cuy
> Pietenpol-List: Eric kicking some spruce !!!
Original Posted By: Doc Mosher
Well Mike, I sure wish that were the case. Unfortunately you must have read that message wrong - it was Dave Rowe who wrote about building his fuse frame in a week. He wrote that in response to my earlier message. Man I really hate to disappoint you after giving me those accolades so I guess I had better get busy to keep up with Dave.My wife told me she would support my airplane building as long as I finish the half-completed boat that I'm currently building in the garage now. I'm thinking maybe I can sneak out there in the middle of the night and cut a little spruce though. I can see it now - she'll catch me coming in the house late and say "Is that sawdust on your collar!?">From: Michael D Cuy >Reply-To: pietenpol-list(at)matronics.com>To: pietenpol-list(at)matronics.com>Subject: Pietenpol-List: Eric kicking some spruce !!!>Date: Wed, 19 Nov 2003 11:48:08 -0500>>>>> >Eric Williams wrote.........In a week of evenings and a couple of> >weekends, I had a completed> >fuselage frame in my shop. For the peace of mind it's definately worth> >it to start fresh.>>>Eric ! Way to go. It's great hearing this and shows hopeful builders that>framing up a Piet fuselage is not that big of a time-consuming>thing. Progress CAN be made quickly.>>Mike C.>>From the hottest toys to tips on keeping fit this winter, youll find a range of helpful holiday info here. http://special.msn.com/network/happyhol ... ______Date: Wed, 19 Nov 2003 13:53:34 -0600
Well Mike, I sure wish that were the case. Unfortunately you must have read that message wrong - it was Dave Rowe who wrote about building his fuse frame in a week. He wrote that in response to my earlier message. Man I really hate to disappoint you after giving me those accolades so I guess I had better get busy to keep up with Dave.My wife told me she would support my airplane building as long as I finish the half-completed boat that I'm currently building in the garage now. I'm thinking maybe I can sneak out there in the middle of the night and cut a little spruce though. I can see it now - she'll catch me coming in the house late and say "Is that sawdust on your collar!?">From: Michael D Cuy >Reply-To: pietenpol-list(at)matronics.com>To: pietenpol-list(at)matronics.com>Subject: Pietenpol-List: Eric kicking some spruce !!!>Date: Wed, 19 Nov 2003 11:48:08 -0500>>>>> >Eric Williams wrote.........In a week of evenings and a couple of> >weekends, I had a completed> >fuselage frame in my shop. For the peace of mind it's definately worth> >it to start fresh.>>>Eric ! Way to go. It's great hearing this and shows hopeful builders that>framing up a Piet fuselage is not that big of a time-consuming>thing. Progress CAN be made quickly.>>Mike C.>>From the hottest toys to tips on keeping fit this winter, youll find a range of helpful holiday info here. http://special.msn.com/network/happyhol ... ______Date: Wed, 19 Nov 2003 13:53:34 -0600
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Re: Pietenpol-List: Misc info
Original Posted By: "Jim Vydra"
did you not put them on ebay, Jim?What are they, specifiaclly?Chris bobka----- Original Message -----
did you not put them on ebay, Jim?What are they, specifiaclly?Chris bobka----- Original Message -----
Pietenpol-List: Misc info
Original Posted By: Kip & Beth Gardner
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
RE: Pietenpol-List: Good Fuselage??
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Gene, aren't you getting a little tired of sending the same old email?Jack -----Original Message-----
Gene, aren't you getting a little tired of sending the same old email?Jack -----Original Message-----
Re: Pietenpol-List: Good Fuselage??
Original Posted By: "Hubbard, Eugene"
On my minimax the plans call for a strip of 1/8" mahogany plywood, about 13/4" wide by 7' long from the cockpit back to the tail on all outsidecorners of the longerons. It also has cross braces in the back part of thefuselage.Dennis----- Original Message -----
On my minimax the plans call for a strip of 1/8" mahogany plywood, about 13/4" wide by 7' long from the cockpit back to the tail on all outsidecorners of the longerons. It also has cross braces in the back part of thefuselage.Dennis----- Original Message -----
Re: Pietenpol-List: Good Fuselage??
Original Posted By: "Jack Phillips"
yes, I concur.what's up with that?walt evansNX140DL----- Original Message -----
yes, I concur.what's up with that?walt evansNX140DL----- Original Message -----
Multiple copies of RE: Pietenpol-List: Good Fuselage??
Original Posted By: w b evans [mailto:wbeevans(at)verizon.net]
Sorry about the duplicates. It seems to be an Outlook problem that sendsabout a day and a half of messages every time I reboot. My IT person thinkshe's found the problem (again). No evidence of a virus--just a strangeconfiguration. I hate to say it, but you'll be among the first to know ifit's really fixed.Again, please accept my apologies--I'm tired of reading it too.Gene-----Original Message-----
Sorry about the duplicates. It seems to be an Outlook problem that sendsabout a day and a half of messages every time I reboot. My IT person thinkshe's found the problem (again). No evidence of a virus--just a strangeconfiguration. I hate to say it, but you'll be among the first to know ifit's really fixed.Again, please accept my apologies--I'm tired of reading it too.Gene-----Original Message-----
RE: Pietenpol-List: Good Fuselage??
Original Posted By: Eric Williams [mailto:ewilliams805(at)msn.com]
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----
Eric,First the disclaimer: I'm not a structural engineer, and I haven't run thenumbers for the Piet fuselage. I do understand a lot of the physicsinvolved. I built my Piet fuselage 1 inch spruce longerons. You're calculations are correct, at least for tensile strength. Stiffnessdepends on dimension squared, and goes down even faster. There's a MIL-SPECon spruce--I don't have the number handy, but someone on the list probablydoes. It lists substitution recommendations for other woods, includingDouglas fir.On the other hand, there seems to be a general consensus that the Piet isoverbuilt. You could check into the construction used for other wood planesto get a feeling for what is done. The only data point I (think) I rememberis that I've seen an Ospery I amphibian that appeared to be built of 3/4inch fir.Doublers seem like an interesting idea. If I were going to do it that way,I'd think about 8 long strips on the outsides of the corners, over thegussets, with filler blocks between the gussets. 1/8 inch Douglas fir over1/8 inch filler would probably bring your strength back to nominal.Stiffness would (probably) be better than using 1" spruce. I'd worry a bitabout using a spruce doubler over Douglas Fir because of a difference instiffness (Young's modulus to be specific).Let us know how you decide to go.Gene HubbardSan Diego-----Original Message-----