Original Posted By: "jimd"
OK guys, another question from the integrity nut. I have the 36" center section, and I want to know the correct attach point for my wing struts. Right now I put them as per plans with the regular center section. By using the 36" section does that automatically place them at the correct position? Also, where to put the jury struts? Gardiner Mason________________________________________________________________________________Subject: Pietenpol-List: Leading Edge spar .. how do you shape it?
Pietenpol-List: Leading Edge spar .. how do you shape it?
Original Posted By: "DJ Vegh"
I have leading edges that need wood spars with the wings airfoil shape. How doyou guys create a spar with the shape you need, at a reasonable cost, in a reasonableamount of time?Not being much of a woodworker, each idea I have had seems problematic;Router; have one, never used it. Could try to make a jig to make repeated cutsto approximate shape of airfoil. Getting something that would hold the positionprecisely, in many different positions seems dicey.Spar is about 3 inches wide, so no way my router could do it in less than 3-4 passes,and getting profile right would be tough, don't think it would match anynormal router bits exactly.Shaper; there are companies that make custom shaper cutters that would make onefor that shape. Very expensive and I don't have a shaper.CNC; companies will make about anything you want if you provide info. Only needtwo spars and would rather do it self somehow.Don't do it as one big piece.. thought about putting plywood airfoil shaped pieceson each rib, with about a one inch square opening for a piece of wood, thenI could use longeron stock. Would end up lighter, could do with jigsaw and files.However it wouldn't provide much support to the leading edge skin as itwould only make contact at each rib.This is for a GN-1 Biplane, which confuses the issue a little. The top wings arecomplete, they have a .026 aluminum wrapped leading edge with a square 1" sparthat touches the leading edge in two spots the full length of the wings. (Thesquare part is along the very front of each rib) so it provides some support.)The lower wing is what needs the spars, and then to be skinned with something.My plans show a single piece of wood shaped to match the airfoil profile, attachedvia flat head machine screws/bolts, at each rib.There is no indication of wood or aluminum for leading edge skin. Since my topwings have aluminum, and I am comfortable working with it I was leaning towardskinning it with aluminum.Preference would be to follow plans, which would be to make up an airfoil shapedspar. How did you guys do this?I have a picture (not my plane, but same exact kind of shaped piece) as an exampleof what I think I need.Any help would be appreciated.JimRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/lead ... __________
I have leading edges that need wood spars with the wings airfoil shape. How doyou guys create a spar with the shape you need, at a reasonable cost, in a reasonableamount of time?Not being much of a woodworker, each idea I have had seems problematic;Router; have one, never used it. Could try to make a jig to make repeated cutsto approximate shape of airfoil. Getting something that would hold the positionprecisely, in many different positions seems dicey.Spar is about 3 inches wide, so no way my router could do it in less than 3-4 passes,and getting profile right would be tough, don't think it would match anynormal router bits exactly.Shaper; there are companies that make custom shaper cutters that would make onefor that shape. Very expensive and I don't have a shaper.CNC; companies will make about anything you want if you provide info. Only needtwo spars and would rather do it self somehow.Don't do it as one big piece.. thought about putting plywood airfoil shaped pieceson each rib, with about a one inch square opening for a piece of wood, thenI could use longeron stock. Would end up lighter, could do with jigsaw and files.However it wouldn't provide much support to the leading edge skin as itwould only make contact at each rib.This is for a GN-1 Biplane, which confuses the issue a little. The top wings arecomplete, they have a .026 aluminum wrapped leading edge with a square 1" sparthat touches the leading edge in two spots the full length of the wings. (Thesquare part is along the very front of each rib) so it provides some support.)The lower wing is what needs the spars, and then to be skinned with something.My plans show a single piece of wood shaped to match the airfoil profile, attachedvia flat head machine screws/bolts, at each rib.There is no indication of wood or aluminum for leading edge skin. Since my topwings have aluminum, and I am comfortable working with it I was leaning towardskinning it with aluminum.Preference would be to follow plans, which would be to make up an airfoil shapedspar. How did you guys do this?I have a picture (not my plane, but same exact kind of shaped piece) as an exampleof what I think I need.Any help would be appreciated.JimRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/lead ... __________
Re: Pietenpol-List: Leading Edge spar .. how do you shape it?
Original Posted By: "jimd"
this is something you can do like they did in the "old days" I would do it by hand with a large jack plane. Keep the knife sharp and it'll shave off Spruce like butter. Just get the profile close with the plane and then make yourself a 16" sanding block with something like 80 grit to round it off and then some 150 grit by hand.Just keep the knife sharp! and don't cut into the grain.DJ----- Original Message -----
this is something you can do like they did in the "old days" I would do it by hand with a large jack plane. Keep the knife sharp and it'll shave off Spruce like butter. Just get the profile close with the plane and then make yourself a 16" sanding block with something like 80 grit to round it off and then some 150 grit by hand.Just keep the knife sharp! and don't cut into the grain.DJ----- Original Message -----
RE: Pietenpol-List: Leading Edge spar .. how do you shape it?
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Several cuts on a table saw with the blade at various angles or differentrouter bits on a router table should also be able to get it close.Brian KrautEngineering Alternatives, Inc.www.engalt.com-----Original Message-----
Several cuts on a table saw with the blade at various angles or differentrouter bits on a router table should also be able to get it close.Brian KrautEngineering Alternatives, Inc.www.engalt.com-----Original Message-----
Pietenpol-List: Leading Edge spar .. how do you shape it?
Original Posted By: shad bell
RE: Pietenpol-List: Leading Edge spar .. how do you shape it?
Original Posted By: "Phillips, Jack"
I cut four facets out of a 1" X 2 1/4" spruce board on my inexpensive table saw. It leaves very little sanding or planeing to finish it. I cut a piece of scrap to the same size, marked out the shape of the leading edge on the end of it and used it to set and try the blade angels before makeing the cuts on the real thing..Worked great for me..Ed G.>From: "jimd" >Reply-To: pietenpol-list(at)matronics.com>To: pietenpol-list(at)matronics.com>Subject: Pietenpol-List: Leading Edge spar .. how do you shape it?>Date: Sun, 11 Nov 2007 07:23:21 -0800>>>I have leading edges that need wood spars with the wings airfoil shape. How >do you guys create a spar with the shape you need, at a reasonable cost, in >a reasonable amount of time?>>Not being much of a woodworker, each idea I have had seems problematic;>>Router; have one, never used it. Could try to make a jig to make repeated >cuts to approximate shape of airfoil. Getting something that would hold the >position precisely, in many different positions seems dicey.>Spar is about 3 inches wide, so no way my router could do it in less than >3-4 passes, and getting profile right would be tough, don't think it would >match any normal router bits exactly.>>Shaper; there are companies that make custom shaper cutters that would make >one for that shape. Very expensive and I don't have a shaper.>>CNC; companies will make about anything you want if you provide info. Only >need two spars and would rather do it self somehow.>>Don't do it as one big piece.. thought about putting plywood airfoil shaped >pieces on each rib, with about a one inch square opening for a piece of >wood, then I could use longeron stock. Would end up lighter, could do with >jigsaw and files. However it wouldn't provide much support to the leading >edge skin as it would only make contact at each rib.>>This is for a GN-1 Biplane, which confuses the issue a little. The top >wings are complete, they have a .026 aluminum wrapped leading edge with a >square 1" spar that touches the leading edge in two spots the full length >of the wings. (The square part is along the very front of each rib) so it >provides some support.)>>The lower wing is what needs the spars, and then to be skinned with >something. My plans show a single piece of wood shaped to match the airfoil >profile, attached via flat head machine screws/bolts, at each rib.>There is no indication of wood or aluminum for leading edge skin. Since my >top wings have aluminum, and I am comfortable working with it I was leaning >toward skinning it with aluminum.>>Preference would be to follow plans, which would be to make up an airfoil >shaped spar. How did you guys do this?>>I have a picture (not my plane, but same exact kind of shaped piece) as an >example of what I think I need.>>Any help would be appreciated.>>Jim>>>Read this topic online here:>>http://forums.matronics.com/viewtopic.p ... ___Subject: RE: Pietenpol-List: Leading Edge spar .. how do you shape it?Date: Mon, 12 Nov 2007 14:02:10 -0500
I cut four facets out of a 1" X 2 1/4" spruce board on my inexpensive table saw. It leaves very little sanding or planeing to finish it. I cut a piece of scrap to the same size, marked out the shape of the leading edge on the end of it and used it to set and try the blade angels before makeing the cuts on the real thing..Worked great for me..Ed G.>From: "jimd" >Reply-To: pietenpol-list(at)matronics.com>To: pietenpol-list(at)matronics.com>Subject: Pietenpol-List: Leading Edge spar .. how do you shape it?>Date: Sun, 11 Nov 2007 07:23:21 -0800>>>I have leading edges that need wood spars with the wings airfoil shape. How >do you guys create a spar with the shape you need, at a reasonable cost, in >a reasonable amount of time?>>Not being much of a woodworker, each idea I have had seems problematic;>>Router; have one, never used it. Could try to make a jig to make repeated >cuts to approximate shape of airfoil. Getting something that would hold the >position precisely, in many different positions seems dicey.>Spar is about 3 inches wide, so no way my router could do it in less than >3-4 passes, and getting profile right would be tough, don't think it would >match any normal router bits exactly.>>Shaper; there are companies that make custom shaper cutters that would make >one for that shape. Very expensive and I don't have a shaper.>>CNC; companies will make about anything you want if you provide info. Only >need two spars and would rather do it self somehow.>>Don't do it as one big piece.. thought about putting plywood airfoil shaped >pieces on each rib, with about a one inch square opening for a piece of >wood, then I could use longeron stock. Would end up lighter, could do with >jigsaw and files. However it wouldn't provide much support to the leading >edge skin as it would only make contact at each rib.>>This is for a GN-1 Biplane, which confuses the issue a little. The top >wings are complete, they have a .026 aluminum wrapped leading edge with a >square 1" spar that touches the leading edge in two spots the full length >of the wings. (The square part is along the very front of each rib) so it >provides some support.)>>The lower wing is what needs the spars, and then to be skinned with >something. My plans show a single piece of wood shaped to match the airfoil >profile, attached via flat head machine screws/bolts, at each rib.>There is no indication of wood or aluminum for leading edge skin. Since my >top wings have aluminum, and I am comfortable working with it I was leaning >toward skinning it with aluminum.>>Preference would be to follow plans, which would be to make up an airfoil >shaped spar. How did you guys do this?>>I have a picture (not my plane, but same exact kind of shaped piece) as an >example of what I think I need.>>Any help would be appreciated.>>Jim>>>Read this topic online here:>>http://forums.matronics.com/viewtopic.p ... ___Subject: RE: Pietenpol-List: Leading Edge spar .. how do you shape it?Date: Mon, 12 Nov 2007 14:02:10 -0500
Re: Pietenpol-List: Leading Edge spar .. how do you shape it?
Original Posted By: "walt evans"
Subject: Re: Pietenpol-List: Leading Edge spar .. how do you shape it?When one builds AND flies his own aeronautical creation down discount the favors the angels might provide.Corky 1:13________________________________________________________________________________Date: Mon, 12 Nov 2007 16:44:30 -0500
Subject: Re: Pietenpol-List: Leading Edge spar .. how do you shape it?When one builds AND flies his own aeronautical creation down discount the favors the angels might provide.Corky 1:13________________________________________________________________________________Date: Mon, 12 Nov 2007 16:44:30 -0500
Pietenpol-List: Re: Leading airfoil shape-- scalloped back edge
Original Posted By: "walt evans"
Pietenpol-List:
Original Posted By: Rcaprd(at)aol.com
Who do we have in the Greensboro area? I will be there tomorrow, and then Greenville-Spartanburg on Thursday. I'd like to visit anyone in those areas if possible.Gene________________________________________________________________________________
Who do we have in the Greensboro area? I will be there tomorrow, and then Greenville-Spartanburg on Thursday. I'd like to visit anyone in those areas if possible.Gene________________________________________________________________________________
Re: Pietenpol-List: Re: Leading airfoil shape-- scalloped back edge
Original Posted By: "Brian Kraut"
Subject: Re: Pietenpol-List: Re: Leading airfoil shape-- scalloped back edgeIn a message dated 11/12/2007 7:41:07 AM Central Standard Time, timothywillis(at)earthlink.net writes:While we are discussing putting thin plywood on the face of the wings to shape the airfoil, what about the scalloped rear edge of any such plywood skins?I know this is a long way in sophistication from Mother's Oats stuff first used by BP, but is it a real improvment? What does it really do? I understandthe concept of the fabric lifting between the scallops while in flight, but what do the scallops really do?Tim,The scallops are not needed in the 1/16" plywood leading edge material. It doesn't do anything. When the fabric is shrunk to spec., it pulls the aft edgeof the plywood down very nicely. Cutting scallops DOES require much more work. I don't believe the fabric ever lifts between the ribs, however, the onlytime the fabric could possibly lift between the ribs, might be in a very high G load maneuver...probably more than the airframe can even handle. Stick to the plans, and 'Git 'er done' !!Chuck G.NX770CG________________________________________________________________________________
Subject: Re: Pietenpol-List: Re: Leading airfoil shape-- scalloped back edgeIn a message dated 11/12/2007 7:41:07 AM Central Standard Time, timothywillis(at)earthlink.net writes:While we are discussing putting thin plywood on the face of the wings to shape the airfoil, what about the scalloped rear edge of any such plywood skins?I know this is a long way in sophistication from Mother's Oats stuff first used by BP, but is it a real improvment? What does it really do? I understandthe concept of the fabric lifting between the scallops while in flight, but what do the scallops really do?Tim,The scallops are not needed in the 1/16" plywood leading edge material. It doesn't do anything. When the fabric is shrunk to spec., it pulls the aft edgeof the plywood down very nicely. Cutting scallops DOES require much more work. I don't believe the fabric ever lifts between the ribs, however, the onlytime the fabric could possibly lift between the ribs, might be in a very high G load maneuver...probably more than the airframe can even handle. Stick to the plans, and 'Git 'er done' !!Chuck G.NX770CG________________________________________________________________________________
> Pietenpol-List: Leading Edge spar .. how do you shape it?
Original Posted By: Isablcorky(at)aol.com
>>>I have leading edges that need wood spars with the wings airfoil shape.>How do you guys create a spar with the shape you need, at a reasonable >cost, in a reasonable amount of time?>>Not being much of a woodworker, each idea I have had seems problematic;>>Router; have one, never used it. Could try to make a jig to make >repeated cuts to approximate shape of airfoil. Getting something that >would hold the position precisely, in many different positions seemsdicey.>Spar is about 3 inches wide, so no way my router could do it in less >than>3-4 passes, and getting profile right would be tough, don't think it >would match any normal router bits exactly.>>Shaper; there are companies that make custom shaper cutters that would >make one for that shape. Very expensive and I don't have a shaper.>>CNC; companies will make about anything you want if you provide info. >Only need two spars and would rather do it self somehow.>>Don't do it as one big piece.. thought about putting plywood airfoil >shaped pieces on each rib, with about a one inch square opening for a >piece of wood, then I could use longeron stock. Would end up lighter, >could do with jigsaw and files. However it wouldn't provide much >support to the leading edge skin as it would only make contact at eachrib.>>This is for a GN-1 Biplane, which confuses the issue a little. The top >wings are complete, they have a .026 aluminum wrapped leading edge with>a square 1" spar that touches the leading edge in two spots the full >length of the wings. (The square part is along the very front of each >rib) so it provides some support.)>>The lower wing is what needs the spars, and then to be skinned with >something. My plans show a single piece of wood shaped to match the >airfoil profile, attached via flat head machine screws/bolts, at eachrib.>There is no indication of wood or aluminum for leading edge skin. Since>my top wings have aluminum, and I am comfortable working with it I was >leaning toward skinning it with aluminum.>>Preference would be to follow plans, which would be to make up an >airfoil shaped spar. How did you guys do this?>>I have a picture (not my plane, but same exact kind of shaped piece) as>an example of what I think I need.>>Any help would be appreciated.>>Jim>>>Read this topic online here:>>http://forums.matronics.com/viewtopic.p ... ________or otherwise private information. If you have received it in error, please notifythe senderDansk - Deutsch - Espanol - Francais - Italiano - Japanese - Nederlands - Norsk- Portuguese________________________________________________________________________________
>>>I have leading edges that need wood spars with the wings airfoil shape.>How do you guys create a spar with the shape you need, at a reasonable >cost, in a reasonable amount of time?>>Not being much of a woodworker, each idea I have had seems problematic;>>Router; have one, never used it. Could try to make a jig to make >repeated cuts to approximate shape of airfoil. Getting something that >would hold the position precisely, in many different positions seemsdicey.>Spar is about 3 inches wide, so no way my router could do it in less >than>3-4 passes, and getting profile right would be tough, don't think it >would match any normal router bits exactly.>>Shaper; there are companies that make custom shaper cutters that would >make one for that shape. Very expensive and I don't have a shaper.>>CNC; companies will make about anything you want if you provide info. >Only need two spars and would rather do it self somehow.>>Don't do it as one big piece.. thought about putting plywood airfoil >shaped pieces on each rib, with about a one inch square opening for a >piece of wood, then I could use longeron stock. Would end up lighter, >could do with jigsaw and files. However it wouldn't provide much >support to the leading edge skin as it would only make contact at eachrib.>>This is for a GN-1 Biplane, which confuses the issue a little. The top >wings are complete, they have a .026 aluminum wrapped leading edge with>a square 1" spar that touches the leading edge in two spots the full >length of the wings. (The square part is along the very front of each >rib) so it provides some support.)>>The lower wing is what needs the spars, and then to be skinned with >something. My plans show a single piece of wood shaped to match the >airfoil profile, attached via flat head machine screws/bolts, at eachrib.>There is no indication of wood or aluminum for leading edge skin. Since>my top wings have aluminum, and I am comfortable working with it I was >leaning toward skinning it with aluminum.>>Preference would be to follow plans, which would be to make up an >airfoil shaped spar. How did you guys do this?>>I have a picture (not my plane, but same exact kind of shaped piece) as>an example of what I think I need.>>Any help would be appreciated.>>Jim>>>Read this topic online here:>>http://forums.matronics.com/viewtopic.p ... ________or otherwise private information. If you have received it in error, please notifythe senderDansk - Deutsch - Espanol - Francais - Italiano - Japanese - Nederlands - Norsk- Portuguese________________________________________________________________________________
