Original Posted By: Kip & Beth Gardner
I just placed my order for aluminumn streamlined lift struts from CarlsonAircraft. I also ordered some of thier streamline jury strut material.For an extra $18.50 they also sent a kit to install the jury struts. The kitcomes with terminating ends and strap material. best part is the entirebill came to $222.50 plus shipping! try that with 4130 streamline!I had them cut my struts at 100" that gives me 26" of fall-off. I'mconsidering using the fall-off as cabane struts. The person at Carlsonsaid if I was in any doubt as to strength I could stick a 1" square pieceall the way through. I like the idea. Have any others out there used thealuminum for cabane struts??DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV________________________________________________________________________________Date: Tue, 5 Mar 2002 10:37:53 -0500
Pietenpol-List: aluminum lift/jury struts
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: John Hofmann
>>I just placed my order for aluminumn streamlined lift struts from Carlson>Aircraft. I also ordered some of thier streamline jury strut material.>For an extra $18.50 they also sent a kit to install the jury struts. The kit>comes with terminating ends and strap material. best part is the entire>bill came to $222.50 plus shipping! try that with 4130 streamline!>>I had them cut my struts at 100" that gives me 26" of fall-off. I'm>considering using the fall-off as cabane struts. The person at Carlson>said if I was in any doubt as to strength I could stick a 1" square piece>all the way through. I like the idea. Have any others out there used the>aluminum for cabane struts??>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>________________________________________________________________________________Date: Tue, 05 Mar 2002 14:50:47 -0600Subject: Re: Pietenpol-List: aluminum lift/jury struts
>>I just placed my order for aluminumn streamlined lift struts from Carlson>Aircraft. I also ordered some of thier streamline jury strut material.>For an extra $18.50 they also sent a kit to install the jury struts. The kit>comes with terminating ends and strap material. best part is the entire>bill came to $222.50 plus shipping! try that with 4130 streamline!>>I had them cut my struts at 100" that gives me 26" of fall-off. I'm>considering using the fall-off as cabane struts. The person at Carlson>said if I was in any doubt as to strength I could stick a 1" square piece>all the way through. I like the idea. Have any others out there used the>aluminum for cabane struts??>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>________________________________________________________________________________Date: Tue, 05 Mar 2002 14:50:47 -0600Subject: Re: Pietenpol-List: aluminum lift/jury struts
RE: Pietenpol-List: I found a great lumber yard in Houston
Original Posted By: "Gary McNeel, Jr."
>>OK Ohio Pieters!>>Since I don't plan on traveling to Houston any time soon, so any of you OH>guys know of any good local sources of lumber & plywood? The only>independent lumber yard nearby (as opposed to any of the 'evil empire'>mega-stores) carries a small amount of Douglas fir, mostly in 2x10 (x>16'!), and it's lousy quality, aircraft-wise. So far, they are the only>place around here I've found that carries Resorcinol glue & no one has even>heard of T-88!>>I don't mind travelling some, but Houston is a tad too far!>>Luckily, I have a manufacturer of AN hardware 2 blocks up the street from>my house, so that part of the project is covered!>>Cheers!>>Kip Gardner>>>426 Schneider St. SE>North Canton, OH 44720>(330) 494-1775>>________________________________________________________________________________Date: Tue, 5 Mar 2002 12:56:25 -0500
>>OK Ohio Pieters!>>Since I don't plan on traveling to Houston any time soon, so any of you OH>guys know of any good local sources of lumber & plywood? The only>independent lumber yard nearby (as opposed to any of the 'evil empire'>mega-stores) carries a small amount of Douglas fir, mostly in 2x10 (x>16'!), and it's lousy quality, aircraft-wise. So far, they are the only>place around here I've found that carries Resorcinol glue & no one has even>heard of T-88!>>I don't mind travelling some, but Houston is a tad too far!>>Luckily, I have a manufacturer of AN hardware 2 blocks up the street from>my house, so that part of the project is covered!>>Cheers!>>Kip Gardner>>>426 Schneider St. SE>North Canton, OH 44720>(330) 494-1775>>________________________________________________________________________________Date: Tue, 5 Mar 2002 12:56:25 -0500
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "Fisherman Caye"
Ray,not sure what your concern on cost is.... the entire aluminum strut orderI placed today came up to $222 plus shipping. That was for 4 lift struts,4 cabane struts, and jury struts as well as jury strut assembly kit.To do all that with 4130 streamline would have cost well over $1200. Thatsone hell of a savings in money and a few pounds lighter in weight.go to www.sky-tek.com and check them out.DJ----- Original Message -----
Ray,not sure what your concern on cost is.... the entire aluminum strut orderI placed today came up to $222 plus shipping. That was for 4 lift struts,4 cabane struts, and jury struts as well as jury strut assembly kit.To do all that with 4130 streamline would have cost well over $1200. Thatsone hell of a savings in money and a few pounds lighter in weight.go to www.sky-tek.com and check them out.DJ----- Original Message -----
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "Gary McNeel, Jr."
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "DJ Vegh"
D.J.4130 streamline from Dillsburg Aeroplane for GN-1 lift struts only was$464.00 incl frt. in Jan. 02.DickG, Ft. Myers----- Original Message -----
D.J.4130 streamline from Dillsburg Aeroplane for GN-1 lift struts only was$464.00 incl frt. in Jan. 02.DickG, Ft. Myers----- Original Message -----
> Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: clif
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: John Hofmann
-----Original Message-----Which brings me back to old Piper lift struts. Scrounge around. They arethere and they are useless on a Piper. Take advantage of them.That's what I did. Got one set of J-3 struts for free. I'm negotiating fora second set so I can make all four struts the same size. Hopefully thesecond set will be the same price as the first.Jack________________________________________________________________________________Date: Tue, 05 Mar 2002 15:19:06 -0600Subject: Re: Pietenpol-List: aluminum lift/jury struts
-----Original Message-----Which brings me back to old Piper lift struts. Scrounge around. They arethere and they are useless on a Piper. Take advantage of them.That's what I did. Got one set of J-3 struts for free. I'm negotiating fora second set so I can make all four struts the same size. Hopefully thesecond set will be the same price as the first.Jack________________________________________________________________________________Date: Tue, 05 Mar 2002 15:19:06 -0600Subject: Re: Pietenpol-List: aluminum lift/jury struts
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Gary,there would not be a steel bar run through the lift struts. The struts arehollow extruded aluminum with flats on the inside which are spaced to accepta 1" aluminum .065 square tube. The square tube is inserted only about 4"into the strut and bolted. About 1.5" extends out for attachment to theaircraft.The only place someone MIGHT run an aliminum bar all the way through wouldbe the cabane struts... which is only about 23" or so.Weight savings of the aluminum struts over 4130 is quite significant.4130 large strut material is 1.1lb/ft. Aluminum is .55lb/ft. Thats almosthalf the weight.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV-----Original Message-----
Gary,there would not be a steel bar run through the lift struts. The struts arehollow extruded aluminum with flats on the inside which are spaced to accepta 1" aluminum .065 square tube. The square tube is inserted only about 4"into the strut and bolted. About 1.5" extends out for attachment to theaircraft.The only place someone MIGHT run an aliminum bar all the way through wouldbe the cabane struts... which is only about 23" or so.Weight savings of the aluminum struts over 4130 is quite significant.4130 large strut material is 1.1lb/ft. Aluminum is .55lb/ft. Thats almosthalf the weight.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV-----Original Message-----
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "Jeffrey Wilcox"
>>>Gary,>>there would not be a steel bar run through the lift struts. The struts are>hollow extruded aluminum with flats on the inside which are spaced to accept>a 1" aluminum .065 square tube. The square tube is inserted only about 4">into the strut and bolted. About 1.5" extends out for attachment to the>aircraft.>>The only place someone MIGHT run an aliminum bar all the way through would>be the cabane struts... which is only about 23" or so.>>Weight savings of the aluminum struts over 4130 is quite significant.>>4130 large strut material is 1.1lb/ft. Aluminum is .55lb/ft. Thats almost>half the weight.>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>>-----Original Message----->From: owner-pietenpol-list-server(at)matronics.com>[mailto:owner-pietenpol-list-server(at)matronics.com]On Behalf Of Gary>McNeel, Jr.>>>So how much would running a 1" square steel bar through the strut add to the>weight? That sounds heavy and sort of defeats the purpose of light weight>aluminium struts. Sounds like I need to do some math.>>-Gary in Houston on a beautiful day.>>________________________________________________________________________________
>>>Gary,>>there would not be a steel bar run through the lift struts. The struts are>hollow extruded aluminum with flats on the inside which are spaced to accept>a 1" aluminum .065 square tube. The square tube is inserted only about 4">into the strut and bolted. About 1.5" extends out for attachment to the>aircraft.>>The only place someone MIGHT run an aliminum bar all the way through would>be the cabane struts... which is only about 23" or so.>>Weight savings of the aluminum struts over 4130 is quite significant.>>4130 large strut material is 1.1lb/ft. Aluminum is .55lb/ft. Thats almost>half the weight.>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>>-----Original Message----->From: owner-pietenpol-list-server(at)matronics.com>[mailto:owner-pietenpol-list-server(at)matronics.com]On Behalf Of Gary>McNeel, Jr.>>>So how much would running a 1" square steel bar through the strut add to the>weight? That sounds heavy and sort of defeats the purpose of light weight>aluminium struts. Sounds like I need to do some math.>>-Gary in Houston on a beautiful day.>>________________________________________________________________________________
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "Christian Bobka"
>>>Gary,>>there would not be a steel bar run through the lift struts. The struts are>hollow extruded aluminum with flats on the inside which are spaced toaccept>a 1" aluminum .065 square tube. The square tube is inserted only about 4">into the strut and bolted. About 1.5" extends out for attachment to the>aircraft.>>The only place someone MIGHT run an aliminum bar all the way through would>be the cabane struts... which is only about 23" or so.>>Weight savings of the aluminum struts over 4130 is quite significant.>>4130 large strut material is 1.1lb/ft. Aluminum is .55lb/ft. Thats almost>half the weight.>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>>-----Original Message----->From: owner-pietenpol-list-server(at)matronics.com>[mailto:owner-pietenpol-list-server(at)matronics.com]On Behalf Of Gary>McNeel, Jr.>>>So how much would running a 1" square steel bar through the strut add tothe>weight? That sounds heavy and sort of defeats the purpose of light weight>aluminium struts. Sounds like I need to do some math.>>-Gary in Houston on a beautiful day.>>________________________________________________________________________________
>>>Gary,>>there would not be a steel bar run through the lift struts. The struts are>hollow extruded aluminum with flats on the inside which are spaced toaccept>a 1" aluminum .065 square tube. The square tube is inserted only about 4">into the strut and bolted. About 1.5" extends out for attachment to the>aircraft.>>The only place someone MIGHT run an aliminum bar all the way through would>be the cabane struts... which is only about 23" or so.>>Weight savings of the aluminum struts over 4130 is quite significant.>>4130 large strut material is 1.1lb/ft. Aluminum is .55lb/ft. Thats almost>half the weight.>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>>-----Original Message----->From: owner-pietenpol-list-server(at)matronics.com>[mailto:owner-pietenpol-list-server(at)matronics.com]On Behalf Of Gary>McNeel, Jr.>>>So how much would running a 1" square steel bar through the strut add tothe>weight? That sounds heavy and sort of defeats the purpose of light weight>aluminium struts. Sounds like I need to do some math.>>-Gary in Houston on a beautiful day.>>________________________________________________________________________________
> > Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: Doc Mosher
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: owner-pietenpol-list-server(at)matronics.com
I too wondered about the strength at first. Then I researched it.the large aluminum strut material is rated atultimate @ 23,268 PSIyield @ 20,498 PSIshear @ 14,958 PSIthe large strut has about .7" cross sectional areaEven if you vertically hung three times the entire weight of a max grossedPiet (say 1200lb x 3G = 3600lb) on only ONE strut you'd only see a force ofabout 5100 PSIand like I said that's if you hung 3 Piets from ONE strut vertically.The aircraft these struts were designed for have a higher gross than thePiet and they only use 2 of them rather than 4. If it's strength yourworried about.... no need to.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV-----Original Message-----
I too wondered about the strength at first. Then I researched it.the large aluminum strut material is rated atultimate @ 23,268 PSIyield @ 20,498 PSIshear @ 14,958 PSIthe large strut has about .7" cross sectional areaEven if you vertically hung three times the entire weight of a max grossedPiet (say 1200lb x 3G = 3600lb) on only ONE strut you'd only see a force ofabout 5100 PSIand like I said that's if you hung 3 Piets from ONE strut vertically.The aircraft these struts were designed for have a higher gross than thePiet and they only use 2 of them rather than 4. If it's strength yourworried about.... no need to.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV-----Original Message-----
RE: Pietenpol-List: Cabane struts and other airplane words from the French
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Doc,Also, if you add jury struts midway along the length of the wing struts tokeep them from bowing out up or down when under a compressive load, then thestrut will be four times stronger in compression in regard to column failuremode.Chris Bobka-----Original Message-----
Doc,Also, if you add jury struts midway along the length of the wing struts tokeep them from bowing out up or down when under a compressive load, then thestrut will be four times stronger in compression in regard to column failuremode.Chris Bobka-----Original Message-----
RE: Pietenpol-List: I found a great lumber yard in Houston
Original Posted By: Larry Neal
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: Larry Neal
-----Original Message-----I too wondered about the strength at first. Then I researched it.the large aluminum strut material is rated atultimate @ 23,268 PSIyield @ 20,498 PSIshear @ 14,958 PSIthe large strut has about .7" cross sectional areaEven if you vertically hung three times the entire weight of a max grossedPiet (say 1200lb x 3G = 3600lb) on only ONE strut you'd only see a force ofabout 5100 PSIand like I said that's if you hung 3 Piets from ONE strut vertically.The aircraft these struts were designed for have a higher gross than thePiet and they only use 2 of them rather than 4. If it's strength yourworried about.... no need to.DJ VeghDJ,Be careful how you figure the stresses and loads on your struts. For onething, 3 G's is nothing - you can easily put that much load on your strutsin a steep turn!Better figure that the struts need to carry at least 5 times the load of thefull gross weight of the plane. And don't forget when you are calculatingcross sectional areas that the strut likely won't fail in the middle, or ina place where it has its full cross section. It will likely fail around therivets that attach it to the rest of the structure. Those rivetedconnections are critical, and are the reason for the reinforcing square tubeinside the strut in that area. For rivets to make an effective fasteningsystem they must be bucked, squeezed or pulled with substantial force todeform the rivet, filling any gaps between the original hole and the rivetshank, and pulling the heads tightly against the strut. If you try thiswithout some reinforcing material inside the strut, you will probably crushthe strut. When you rivet this area, for God's sake don't use "pop"rivets.They absolutely do not have the strength to hold against the loads thisjoint will see. As I've said before on this list, the only thing I woulduse "pop" rivets for is a lawn chair for my ex-wife to sit in. Check withCarlson and see what type of rivets they recommend. Don't use a boltedconnection either, thinking that bolts are stronger than rivets. Bolts arestrong, but a bolted connection cannot be a tight fit like you get with aproperly riveted joint, and then you will have a hard steel bolt wallowing ahole in the soft aluminum structure. Good structural rivets like Cherryrivets are better than bolted connections for aluminum structualapplications, unless the joint is specifically designed for a boltedconnection.Cheers,Jack________________________________________________________________________________Date: Wed, 06 Mar 2002 20:10:59 -0600
-----Original Message-----I too wondered about the strength at first. Then I researched it.the large aluminum strut material is rated atultimate @ 23,268 PSIyield @ 20,498 PSIshear @ 14,958 PSIthe large strut has about .7" cross sectional areaEven if you vertically hung three times the entire weight of a max grossedPiet (say 1200lb x 3G = 3600lb) on only ONE strut you'd only see a force ofabout 5100 PSIand like I said that's if you hung 3 Piets from ONE strut vertically.The aircraft these struts were designed for have a higher gross than thePiet and they only use 2 of them rather than 4. If it's strength yourworried about.... no need to.DJ VeghDJ,Be careful how you figure the stresses and loads on your struts. For onething, 3 G's is nothing - you can easily put that much load on your strutsin a steep turn!Better figure that the struts need to carry at least 5 times the load of thefull gross weight of the plane. And don't forget when you are calculatingcross sectional areas that the strut likely won't fail in the middle, or ina place where it has its full cross section. It will likely fail around therivets that attach it to the rest of the structure. Those rivetedconnections are critical, and are the reason for the reinforcing square tubeinside the strut in that area. For rivets to make an effective fasteningsystem they must be bucked, squeezed or pulled with substantial force todeform the rivet, filling any gaps between the original hole and the rivetshank, and pulling the heads tightly against the strut. If you try thiswithout some reinforcing material inside the strut, you will probably crushthe strut. When you rivet this area, for God's sake don't use "pop"rivets.They absolutely do not have the strength to hold against the loads thisjoint will see. As I've said before on this list, the only thing I woulduse "pop" rivets for is a lawn chair for my ex-wife to sit in. Check withCarlson and see what type of rivets they recommend. Don't use a boltedconnection either, thinking that bolts are stronger than rivets. Bolts arestrong, but a bolted connection cannot be a tight fit like you get with aproperly riveted joint, and then you will have a hard steel bolt wallowing ahole in the soft aluminum structure. Good structural rivets like Cherryrivets are better than bolted connections for aluminum structualapplications, unless the joint is specifically designed for a boltedconnection.Cheers,Jack________________________________________________________________________________Date: Wed, 06 Mar 2002 20:10:59 -0600
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: Kip & Beth Gardner
JackI had planned on using 2 bolts on each end through the struts and squaretube.I understand your concern about using only 3G's and a reference. But like Iwas saying that was only one strut. With all four lift struts and 4 cabanestruts carrying load the numbers are much less. I'd imagine it would take9-11 G's to fail the struts and let's be honest .... something else willbreak long before that.My point was that the aluminum lift struts are plenty strong for a pietproviding the attach points are well engineered.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV________________________________________________________________________________Date: Wed, 6 Mar 2002 09:42:20 -0500
JackI had planned on using 2 bolts on each end through the struts and squaretube.I understand your concern about using only 3G's and a reference. But like Iwas saying that was only one strut. With all four lift struts and 4 cabanestruts carrying load the numbers are much less. I'd imagine it would take9-11 G's to fail the struts and let's be honest .... something else willbreak long before that.My point was that the aluminum lift struts are plenty strong for a pietproviding the attach points are well engineered.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV________________________________________________________________________________Date: Wed, 6 Mar 2002 09:42:20 -0500
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "Ed Grentzer"
-----Original Message-----First, the disclaimer that I'm no engineer. I understand the logic forusing rivets that Jack laid out. Now, is there some way of augmenting thatstructure? I'm thinking along the lines of reinforcing the rivets with someof that 'extreme epoxy' that Jim bede demonstrated at our EAA chaptermeeting a few weeks ago. Maybe I'm just blowing smoke, but it seems that ifyou filled in the area around the joint, it would completely immobilizethings. I suppose you'd have to thouroughly clean the steel tubing, as ifyou were applying epoxy primer, but the aluminum wouldn't need any specialprep beyond being clean, dry and scuffed a little.Comments from the engineerinig experts?Kip GardnerKip,Not that I'm an engineering expert, but I am an engineer and have had alittle experience with adhesives. In my experience, a glue joint betweendissimilar metals (e.g., aluminum and steel) often fails due to thermalexpamsion. The two metals have different coefficients of expansion, so anylarge changes in temperature cause a high shear load at the joint. Themetals are going to expand or contract at their expected amounts. Anydifference between their new lengths must be accomodated by the adhesive, orthe joint will fail. I think DJ is talking about slipping an aluminumsquare tube inside his strut, not a steel tube. In that case, applyingBede's miracle epoxy would probably be a good thing.One thing to remember when substituting aluminum for steel in structures isthat steel has much better resistance to fatigue than aluminum. There is afactor in materials science called "endurance limit", which is a stresslevel below which no fatigue will occur, no matter how many vibration cyclesthe piece sees in service. For steel, the endurance limit is usually lessthan half the yield strength of the material, but aluminum has no endurancelimit - which means that given enough time and enough vibration cycles,aluminum will eventually develop fatigue cracks. Don't get me wrong here -aluminum is a great material for aircraft construction, but you have tounderstand its characteristics and design accordingly. If you use aluminumfor lift struts, be sure you use jury struts and don't mount the jury strutsin the center of the lift strut - mount them enough off-center that theywill tend to break up any harmonic vibration of the strut.Another thing to consider when substituting aluminum for steel is that, allother factors being equal, aluminum is only about 1/3 as stiff as steel,which means that an aluminum part will deflect under load roughly 3 times asmuch as a steel member of the same size and shape. Just things to consider.Jack________________________________________________________________________________
-----Original Message-----First, the disclaimer that I'm no engineer. I understand the logic forusing rivets that Jack laid out. Now, is there some way of augmenting thatstructure? I'm thinking along the lines of reinforcing the rivets with someof that 'extreme epoxy' that Jim bede demonstrated at our EAA chaptermeeting a few weeks ago. Maybe I'm just blowing smoke, but it seems that ifyou filled in the area around the joint, it would completely immobilizethings. I suppose you'd have to thouroughly clean the steel tubing, as ifyou were applying epoxy primer, but the aluminum wouldn't need any specialprep beyond being clean, dry and scuffed a little.Comments from the engineerinig experts?Kip GardnerKip,Not that I'm an engineering expert, but I am an engineer and have had alittle experience with adhesives. In my experience, a glue joint betweendissimilar metals (e.g., aluminum and steel) often fails due to thermalexpamsion. The two metals have different coefficients of expansion, so anylarge changes in temperature cause a high shear load at the joint. Themetals are going to expand or contract at their expected amounts. Anydifference between their new lengths must be accomodated by the adhesive, orthe joint will fail. I think DJ is talking about slipping an aluminumsquare tube inside his strut, not a steel tube. In that case, applyingBede's miracle epoxy would probably be a good thing.One thing to remember when substituting aluminum for steel in structures isthat steel has much better resistance to fatigue than aluminum. There is afactor in materials science called "endurance limit", which is a stresslevel below which no fatigue will occur, no matter how many vibration cyclesthe piece sees in service. For steel, the endurance limit is usually lessthan half the yield strength of the material, but aluminum has no endurancelimit - which means that given enough time and enough vibration cycles,aluminum will eventually develop fatigue cracks. Don't get me wrong here -aluminum is a great material for aircraft construction, but you have tounderstand its characteristics and design accordingly. If you use aluminumfor lift struts, be sure you use jury struts and don't mount the jury strutsin the center of the lift strut - mount them enough off-center that theywill tend to break up any harmonic vibration of the strut.Another thing to consider when substituting aluminum for steel is that, allother factors being equal, aluminum is only about 1/3 as stiff as steel,which means that an aluminum part will deflect under load roughly 3 times asmuch as a steel member of the same size and shape. Just things to consider.Jack________________________________________________________________________________
> RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: Michael D Cuy
Looking at the Sky-tek specs. I would be willing to bet that the smaller 2.44" aluminum struts would be way more than up to the task of handling the loads in a Piet wing and would be closer to the2 3/8" X 1" size called for in the plans, with jury struts of course.Plus they are lighter and down right cheap. Heck there's a Piet down here in Fl. that's been flying since the sixties with wood/steel laminated struts. I'm no engineer so what do you guys think about using four of the smaller struts. Don't want to start anything but the Sky-tek4-A extruded aluminum spars look real interesting too at 45,000 psi tensile and 9 pounds. Ed G.>From: "DJ Vegh" >Reply-To: pietenpol-list(at)matronics.com>To: >Subject: RE: Pietenpol-List: aluminum lift/jury struts>Date: Wed, 6 Mar 2002 07:29:18 -0700>>>Jack>>I had planned on using 2 bolts on each end through the struts and square>tube.>>I understand your concern about using only 3G's and a reference. But like >I>was saying that was only one strut. With all four lift struts and 4 cabane>struts carrying load the numbers are much less. I'd imagine it would take>9-11 G's to fail the struts and let's be honest .... something else will>break long before that.>>My point was that the aluminum lift struts are plenty strong for a piet>providing the attach points are well engineered.>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>MSN Photos is the easiest way to share and print your photos: http://photos.msn.com/support/worldwide ... ______Date: Wed, 06 Mar 2002 10:52:52 -0500
Looking at the Sky-tek specs. I would be willing to bet that the smaller 2.44" aluminum struts would be way more than up to the task of handling the loads in a Piet wing and would be closer to the2 3/8" X 1" size called for in the plans, with jury struts of course.Plus they are lighter and down right cheap. Heck there's a Piet down here in Fl. that's been flying since the sixties with wood/steel laminated struts. I'm no engineer so what do you guys think about using four of the smaller struts. Don't want to start anything but the Sky-tek4-A extruded aluminum spars look real interesting too at 45,000 psi tensile and 9 pounds. Ed G.>From: "DJ Vegh" >Reply-To: pietenpol-list(at)matronics.com>To: >Subject: RE: Pietenpol-List: aluminum lift/jury struts>Date: Wed, 6 Mar 2002 07:29:18 -0700>>>Jack>>I had planned on using 2 bolts on each end through the struts and square>tube.>>I understand your concern about using only 3G's and a reference. But like >I>was saying that was only one strut. With all four lift struts and 4 cabane>struts carrying load the numbers are much less. I'd imagine it would take>9-11 G's to fail the struts and let's be honest .... something else will>break long before that.>>My point was that the aluminum lift struts are plenty strong for a piet>providing the attach points are well engineered.>>DJ Vegh>Mesa, AZ>GN-1 Builder>www.raptoronline.com>N74DV>>MSN Photos is the easiest way to share and print your photos: http://photos.msn.com/support/worldwide ... ______Date: Wed, 06 Mar 2002 10:52:52 -0500
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: Kent Hallsten
I'm not real current on my physics, but having four struts would not dividethe stress into fourths, each strut would "feel" the entire load. Standardcategory aircraft are stressed to 3.8G and utility category are stressed to4.4G. I have seen end fittings on Luscombe struts (aluminum struts for themetal wings) that are attached by bolts, but a lot more than two, more likesix.Gene________________________________________________________________________________
I'm not real current on my physics, but having four struts would not dividethe stress into fourths, each strut would "feel" the entire load. Standardcategory aircraft are stressed to 3.8G and utility category are stressed to4.4G. I have seen end fittings on Luscombe struts (aluminum struts for themetal wings) that are attached by bolts, but a lot more than two, more likesix.Gene________________________________________________________________________________
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "DJ Vegh"
Still say the best kept secret in any older "grass field" airport, that hasany kind of a hanger, you'll find old struts that had to be changed due toAD's in the past. Friend of mine in an airport 16 mi north of me, clued mein. People who replaced these struts just didn't throw the old ones out.lots were from Cub's, that were kind of large, But MORE were from others andthey matched the plans real close. You wind up cutting about a foot offeach end to get the right length, and by doing that the inside can beinspected. All four of mine still had that oil inside. Only damage wasslight surface pitting on the outside, which my AP inspected and said werefine.Check it out, I'm sure you'll hit paydirt.waltNX140DL----- Original Message -----
Still say the best kept secret in any older "grass field" airport, that hasany kind of a hanger, you'll find old struts that had to be changed due toAD's in the past. Friend of mine in an airport 16 mi north of me, clued mein. People who replaced these struts just didn't throw the old ones out.lots were from Cub's, that were kind of large, But MORE were from others andthey matched the plans real close. You wind up cutting about a foot offeach end to get the right length, and by doing that the inside can beinspected. All four of mine still had that oil inside. Only damage wasslight surface pitting on the outside, which my AP inspected and said werefine.Check it out, I'm sure you'll hit paydirt.waltNX140DL----- Original Message -----
Pietenpol-List: aluminum lift/jury struts
Original Posted By: del magsam
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Look at the plans, Ray. It's all listed there. You'll need fittings toattach the wings to the centersection, the centersection to the cabanestruts, for the drag wires and anti-drag wires in the wings, a wholeboatload of sheet steel for the control horns, the aileron horn on thetorque tube, all the little fittings for the control system, all the landinggear fittings, the engine mount, etc. There is an awful lot of steel in awooden airplane. If you wanted to build a Pietenpol to avoid welding, youwould have done better to build a Sonex or an RV-7. But welding is fun. Ifound making all the fittings to be one of the more satisfying parts of thewhole process. It takes a little money, but the end result is worth it.Today I just bought about $20 worth of steel angle iron just to be usedonce, in making a jig for my engine mount. It will be of no use when I'mthrough welding the mount, because I made my fuselage an inch wider thannormal, so I doubt any other Piet builder can use it. I'll have nearly asmuch money invested in the jig as I will have in materials in the enginemount itself, but that's OK because it is the only way to weld up a mountwith sufficient accuracy. Sometimes you just gotta do what you gotta do.Jack -----Original Message-----
Look at the plans, Ray. It's all listed there. You'll need fittings toattach the wings to the centersection, the centersection to the cabanestruts, for the drag wires and anti-drag wires in the wings, a wholeboatload of sheet steel for the control horns, the aileron horn on thetorque tube, all the little fittings for the control system, all the landinggear fittings, the engine mount, etc. There is an awful lot of steel in awooden airplane. If you wanted to build a Pietenpol to avoid welding, youwould have done better to build a Sonex or an RV-7. But welding is fun. Ifound making all the fittings to be one of the more satisfying parts of thewhole process. It takes a little money, but the end result is worth it.Today I just bought about $20 worth of steel angle iron just to be usedonce, in making a jig for my engine mount. It will be of no use when I'mthrough welding the mount, because I made my fuselage an inch wider thannormal, so I doubt any other Piet builder can use it. I'll have nearly asmuch money invested in the jig as I will have in materials in the enginemount itself, but that's OK because it is the only way to weld up a mountwith sufficient accuracy. Sometimes you just gotta do what you gotta do.Jack -----Original Message-----
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "Gary McNeel, Jr."
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: "Gary McNeel, Jr."
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: owner-pietenpol-list-server(at)matronics.com
The weight is divided among the cabane and lift struts... albeit notequally. One strut will not "feel" the entire load. The aluminum struts areplenty strong. A Cessna 150 has only two aluminum struts which are similarin strength to the large extruded ones form Carlson . A Piet has 4 stuts.If you ask me... in a high G situation you'll snap a spar or your back LONGbefore you fail an aluminum strut.As for amount of attatch bolts.. the way I se it is the point is not howmany but how much surface area you can get. two .5" bolts would be about asstrong as four .25" bolts. it's surface area not quantityDJ-----Original Message-----
The weight is divided among the cabane and lift struts... albeit notequally. One strut will not "feel" the entire load. The aluminum struts areplenty strong. A Cessna 150 has only two aluminum struts which are similarin strength to the large extruded ones form Carlson . A Piet has 4 stuts.If you ask me... in a high G situation you'll snap a spar or your back LONGbefore you fail an aluminum strut.As for amount of attatch bolts.. the way I se it is the point is not howmany but how much surface area you can get. two .5" bolts would be about asstrong as four .25" bolts. it's surface area not quantityDJ-----Original Message-----
Re: Pietenpol-List: More learning
Original Posted By: Fisherman Caye
Geez, guys! A good drill press can be had from Sears, Home Depot, orwhatever pretty cheaply. Use good quality bits, and a bit of lite oil,moderate pressure. I can just picture Ray straining against his walls!!!Craig----- Original Message -----
Geez, guys! A good drill press can be had from Sears, Home Depot, orwhatever pretty cheaply. Use good quality bits, and a bit of lite oil,moderate pressure. I can just picture Ray straining against his walls!!!Craig----- Original Message -----
Re: Pietenpol-List: More learning
Original Posted By: "DJ Vegh"
Hey Guys, with the plane almost built, I have broken only one bit. Usea drill press and drill small hole first then bring it up to size instages . For alignment of some of the holes you will need a press.I only use the Vanadium (gold) bits. They cut cleaner, last longer anddon't appear to need oil.________________________________________________________________________________
Hey Guys, with the plane almost built, I have broken only one bit. Usea drill press and drill small hole first then bring it up to size instages . For alignment of some of the holes you will need a press.I only use the Vanadium (gold) bits. They cut cleaner, last longer anddon't appear to need oil.________________________________________________________________________________
Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: DJ Vegh
Not to start a long- unnecessary discussion, but I am right on this. If yoususpend a 1000 lb weight from one cable that branches into two with aspreader bar at the bottom, each of the side cables will support the full1000 lbs. I do not necessarily disagree with your conclusions, only yourreasoning. (except the part about using 2 1/2" bolts, even if you couldfind them, instead of more 1/4" bolts)----- Original Message -----
Not to start a long- unnecessary discussion, but I am right on this. If yoususpend a 1000 lb weight from one cable that branches into two with aspreader bar at the bottom, each of the side cables will support the full1000 lbs. I do not necessarily disagree with your conclusions, only yourreasoning. (except the part about using 2 1/2" bolts, even if you couldfind them, instead of more 1/4" bolts)----- Original Message -----
> Re: Pietenpol-List: aluminum lift/jury struts
Original Posted By: Kirk & Laura Huizenga
RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: owner-pietenpol-list-server(at)matronics.com
"even if I could find 1/2" bolts"?? whats an AN-8 ?? AN-8's are readilyavailable. I'm not going to use AN-8's... I'll probably use 2 or 3 AN-6bolts... I was only saying that as an example.and even if we were to assume that each of the struts would see the entireweight of a max grossed piet (which it wouldn't) in a hypothetical 9Gsituation (10,800lbs) that's still only about 15,000 PSI on the strut.Assuming the attach points are well built, you'll NEVER see a failure of analuminum strut under normal flying conditions. As for fatigue... if Ihave to replace an aluminum strut after 2000 hrs then so be it... It's notcost prohibitive.I'm not trying to drag this thread on... My original point was that forthose who are concerned about strength of aluminum struts, there's no needto be worried. For those of you who remain paranoid... then fine use 4130struts :-)all the mumbo jumbo about cables, weights, and bolts is irrelevant. Thealuminum struts are up to the task. period.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV-----Original Message-----
"even if I could find 1/2" bolts"?? whats an AN-8 ?? AN-8's are readilyavailable. I'm not going to use AN-8's... I'll probably use 2 or 3 AN-6bolts... I was only saying that as an example.and even if we were to assume that each of the struts would see the entireweight of a max grossed piet (which it wouldn't) in a hypothetical 9Gsituation (10,800lbs) that's still only about 15,000 PSI on the strut.Assuming the attach points are well built, you'll NEVER see a failure of analuminum strut under normal flying conditions. As for fatigue... if Ihave to replace an aluminum strut after 2000 hrs then so be it... It's notcost prohibitive.I'm not trying to drag this thread on... My original point was that forthose who are concerned about strength of aluminum struts, there's no needto be worried. For those of you who remain paranoid... then fine use 4130struts :-)all the mumbo jumbo about cables, weights, and bolts is irrelevant. Thealuminum struts are up to the task. period.DJ VeghMesa, AZGN-1 Builderwww.raptoronline.comN74DV-----Original Message-----
RE: Pietenpol-List: Pictures finally posted
Original Posted By: owner-pietenpol-list-server(at)matronics.com
great pictures... I like the paint scheme!DJ-----Original Message-----
great pictures... I like the paint scheme!DJ-----Original Message-----
Pietenpol-List: Pictures finally posted
Original Posted By: Kirk & Laura Huizenga
RE: Pietenpol-List: Pictures finally posted
Original Posted By: "Gary McNeel, Jr."
> Pietenpol-List: Pictures finally posted
Original Posted By: "Gary McNeel, Jr."
RE: Pietenpol-List: Tailwheel springs and harmonics
Original Posted By: clif
interesting post Doc.... I'd have never thought about the tail wheelsprings needing to be mis-matched but it makes sense! I'll make a note ofitDJ________________________________________________________________________________Date: Wed, 06 Mar 2002 22:59:04 -0800
interesting post Doc.... I'd have never thought about the tail wheelsprings needing to be mis-matched but it makes sense! I'll make a note ofitDJ________________________________________________________________________________Date: Wed, 06 Mar 2002 22:59:04 -0800
Original Posted By: "Hubbard, Eugene"
> >> >> I just placed my order for aluminumn streamlined lift struts from Carlson>> Aircraft. I also ordered some of thier streamline jury strut material.>> For an extra $18.50 they also sent a kit to install the jury struts. The kit>> comes with terminating ends and strap material. best part is the entire>> bill came to $222.50 plus shipping! try that with 4130 streamline!>> >> I had them cut my struts at 100" that gives me 26" of fall-off. I'm>> considering using the fall-off as cabane struts. The person at Carlson>> said if I was in any doubt as to strength I could stick a 1" square piece>> all the way through. I like the idea. Have any others out there used the>> aluminum for cabane struts??>> >> DJ Vegh>> Mesa, AZ>> GN-1 Builder>> www.raptoronline.com>> N74DV________________________________________________________________________________
> >> >> I just placed my order for aluminumn streamlined lift struts from Carlson>> Aircraft. I also ordered some of thier streamline jury strut material.>> For an extra $18.50 they also sent a kit to install the jury struts. The kit>> comes with terminating ends and strap material. best part is the entire>> bill came to $222.50 plus shipping! try that with 4130 streamline!>> >> I had them cut my struts at 100" that gives me 26" of fall-off. I'm>> considering using the fall-off as cabane struts. The person at Carlson>> said if I was in any doubt as to strength I could stick a 1" square piece>> all the way through. I like the idea. Have any others out there used the>> aluminum for cabane struts??>> >> DJ Vegh>> Mesa, AZ>> GN-1 Builder>> www.raptoronline.com>> N74DV________________________________________________________________________________
> > RE: Pietenpol-List: aluminum lift/jury struts
Original Posted By: Fisherman Caye
> >> >> >Jack> >> >I had planned on using 2 bolts on each end through the struts and square> >tube.> >> >I understand your concern about using only 3G's and a reference. But like > >I> >was saying that was only one strut. With all four lift struts and 4 cabane> >struts carrying load the numbers are much less. I'd imagine it would take> >9-11 G's to fail the struts and let's be honest .... something else will> >break long before that.> >> >My point was that the aluminum lift struts are plenty strong for a piet> >providing the attach points are well engineered.> >> >DJ Vegh> >Mesa, AZ> >GN-1 Builder> >www.raptoronline.com> >N74DV> >> >> > > MSN Photos is the easiest way to share and print your photos: > http://photos.msn.com/support/worldwide.aspx> > FindLaw - Free Case Law, Jobs, Library, Communityhttp://www.FindLaw.comGet your FREE @JUSTICE.COM email!http://mail.Justice.com________________________________________________________________________________Date: 6 Mar 2002 12:55:30 -0800
> >> >> >Jack> >> >I had planned on using 2 bolts on each end through the struts and square> >tube.> >> >I understand your concern about using only 3G's and a reference. But like > >I> >was saying that was only one strut. With all four lift struts and 4 cabane> >struts carrying load the numbers are much less. I'd imagine it would take> >9-11 G's to fail the struts and let's be honest .... something else will> >break long before that.> >> >My point was that the aluminum lift struts are plenty strong for a piet> >providing the attach points are well engineered.> >> >DJ Vegh> >Mesa, AZ> >GN-1 Builder> >www.raptoronline.com> >N74DV> >> >> > > MSN Photos is the easiest way to share and print your photos: > http://photos.msn.com/support/worldwide.aspx> > FindLaw - Free Case Law, Jobs, Library, Communityhttp://www.FindLaw.comGet your FREE @JUSTICE.COM email!http://mail.Justice.com________________________________________________________________________________Date: 6 Mar 2002 12:55:30 -0800