Original Posted By: "bender"
.. you heat the BEARING. Since the wheel rims maybe painted an or fabric covered.Does not take much heat to soften the retaining compound.I would be careful about the loading forces on the plastic bearings vs. wall thicknessand length. Just make sure you pick the correct one for the application.A bearing disintegrating in a wheel housing on landing or take-off can be downright exciting!--------Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Brake anti-rotation
Pietenpol-List: Brake anti-rotation
Re: Pietenpol-List: Brake anti-rotation
Original Posted By: helspersew(at)aol.com
Hey Guys..I'm messing with brakes today..i decided i like the method of anti-rotation on wood gear axle that Dan and Mikeused...but..What size material is appropriate here ?i have tubing around to weld to the inside gear plate for the "pin" to ride in..andkinda feel like 1/2" tubing would be big enough but the "pin" that slidesinside that is attached to the axle.. ? not sure... solid ?.. tube ?it looks like 3 inches of travel is about right so were not talking about lotsof leverage forces and i'm using external band brakes.. which i know are not veryeffective... just need to be able stop while taxiing.. can't image needingreally big stuff herejeffRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Re: Pietenpol-List: Brake anti-rotation
Hey Guys..I'm messing with brakes today..i decided i like the method of anti-rotation on wood gear axle that Dan and Mikeused...but..What size material is appropriate here ?i have tubing around to weld to the inside gear plate for the "pin" to ride in..andkinda feel like 1/2" tubing would be big enough but the "pin" that slidesinside that is attached to the axle.. ? not sure... solid ?.. tube ?it looks like 3 inches of travel is about right so were not talking about lotsof leverage forces and i'm using external band brakes.. which i know are not veryeffective... just need to be able stop while taxiing.. can't image needingreally big stuff herejeffRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Re: Pietenpol-List: Brake anti-rotation
Original Posted By: bender
Hi Jeff,I don't have my Piet here to look at, but I believe I used 3/8" O.D. tube for the "pin" (quite heavy wall thickness). The "sheath" tube was a bit oversize, and I actually "squished" this tube into an oval shape, in anticipation of unequal forces from side to side (in other words, if one wheel hits a pot hole and the other doesn't, the axle will raise up on one side but not the other. No issues so far, but I have a limited number of landings, maybe 100.Dan HelsperPuryear, TN-----Original Message-----
Hi Jeff,I don't have my Piet here to look at, but I believe I used 3/8" O.D. tube for the "pin" (quite heavy wall thickness). The "sheath" tube was a bit oversize, and I actually "squished" this tube into an oval shape, in anticipation of unequal forces from side to side (in other words, if one wheel hits a pot hole and the other doesn't, the axle will raise up on one side but not the other. No issues so far, but I have a limited number of landings, maybe 100.Dan HelsperPuryear, TN-----Original Message-----
Pietenpol-List: Re: Piet on eBay
Original Posted By: "Cuy, Michael D. (GRC-RXD0)[ASRC AEROSPACE CORP]"
Looks like someone got a deal (the purchaser - not the seller).The only oddity I see is a very odd aileron cable routing. From the photos it appearsthat the aileron control cables have been rerouted so that they don't passthrough the instrument area. That could be a nice feature, BUT... the newroute has the cables seriously impeding access to the front seat. Not sure howanyone would manage to get in that front seat.Bill C.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/aile ... __________
Looks like someone got a deal (the purchaser - not the seller).The only oddity I see is a very odd aileron cable routing. From the photos it appearsthat the aileron control cables have been rerouted so that they don't passthrough the instrument area. That could be a nice feature, BUT... the newroute has the cables seriously impeding access to the front seat. Not sure howanyone would manage to get in that front seat.Bill C.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/aile ... __________
Pietenpol-List: Re: Brake anti-rotation
Original Posted By: "bender"
Thanks Terry.... We'll fly our Piets in formation one day....!Congrats on the plans arriving Chief...... The start of your adventure.....!!The 0-200 would be a good engine choice.....J--------Jake Schultz - curator,Newport Way Air Museum (OK, it's just my home)Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Brake anti-rotation
Thanks Terry.... We'll fly our Piets in formation one day....!Congrats on the plans arriving Chief...... The start of your adventure.....!!The 0-200 would be a good engine choice.....J--------Jake Schultz - curator,Newport Way Air Museum (OK, it's just my home)Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Brake anti-rotation
Original Posted By: "Scott Cutler"
thanks gentleman...did some welding..here it isi had some 5/16 bungee around so i put 14 feet on each side just to check thingsout...easier to preload it won't move with just me on board..jeffRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/bung ... __________
thanks gentleman...did some welding..here it isi had some 5/16 bungee around so i put 14 feet on each side just to check thingsout...easier to preload it won't move with just me on board..jeffRead this topic online here:http://forums.matronics.com/viewtopic.p ... ttachments: http://forums.matronics.com//files/bung ... __________
Re: Pietenpol-List: Re: Brake anti-rotation
Original Posted By: bender
Jeff,Will you be installing anything to prevent chafing of the bungee's on the fasteners?The bungees on NX18235 were being replaced annually (my least favorite job) until we installed a leather cuff to protect the bungees. Greg CardinalMinneapolis -----Original Message-----
Jeff,Will you be installing anything to prevent chafing of the bungee's on the fasteners?The bungees on NX18235 were being replaced annually (my least favorite job) until we installed a leather cuff to protect the bungees. Greg CardinalMinneapolis -----Original Message-----
Re: Pietenpol-List: Re: Rib Jig idea?
Original Posted By: Ryan Mueller
My turn!
- If you want to use that ply contraption,great, but you- will need to drill at least 2" holesunder every glue joint so- the glue falls throughwithout touching anything. Also these holes will benecessary for popping the rib out of the jig.-Now, having said that, personaly I would still usethe flat board covered in saran wrap with blocksand cams screwed to it. Why? Well, the excess-gluethat does drip down hits the saran and flattens out.When you turn the rib over to gusset the other sideyou now have even more gluing surface than the firstside. Right? So what happens to that glue in yourfancy jig with holes in- it? Why, it drips this big blob you have to cut off before glueing down that backside gusset! Trust me, you can clean away excess glueall you want but the next day there will still be a blob!-Clifhttp://www.clifdawson.ca/Homepage4-10-06/Pietenpol.html-Pilots are a rare kind of human. They leave the ordinary surface of the world, to purify their soul in the sky, and they come down to earth, only after receiving the communion of the infinite." Jos=C3=A9 Maria Velasco Ibarra, President of Ecuador-You asked about a CNC rib jig. I say, if you can get it to work, do it.-As others eluded to, with out some homework and some thought, it can be a can of worms. But if you can make it duplicate ribs as drawn, great! Michael PerezKaretaker Aerowww.karetakeraero.com-________________________________________________________________________________Date: Sun, 8 Jan 2012 23:07:48 -0600Subject: Re: Pietenpol-List: Re: Rib Jig idea?
My turn!
- If you want to use that ply contraption,great, but you- will need to drill at least 2" holesunder every glue joint so- the glue falls throughwithout touching anything. Also these holes will benecessary for popping the rib out of the jig.-Now, having said that, personaly I would still usethe flat board covered in saran wrap with blocksand cams screwed to it. Why? Well, the excess-gluethat does drip down hits the saran and flattens out.When you turn the rib over to gusset the other sideyou now have even more gluing surface than the firstside. Right? So what happens to that glue in yourfancy jig with holes in- it? Why, it drips this big blob you have to cut off before glueing down that backside gusset! Trust me, you can clean away excess glueall you want but the next day there will still be a blob!-Clifhttp://www.clifdawson.ca/Homepage4-10-06/Pietenpol.html-Pilots are a rare kind of human. They leave the ordinary surface of the world, to purify their soul in the sky, and they come down to earth, only after receiving the communion of the infinite." Jos=C3=A9 Maria Velasco Ibarra, President of Ecuador-You asked about a CNC rib jig. I say, if you can get it to work, do it.-As others eluded to, with out some homework and some thought, it can be a can of worms. But if you can make it duplicate ribs as drawn, great! Michael PerezKaretaker Aerowww.karetakeraero.com-________________________________________________________________________________Date: Sun, 8 Jan 2012 23:07:48 -0600Subject: Re: Pietenpol-List: Re: Rib Jig idea?Re: Pietenpol-List: Re: Brake anti-rotation
Original Posted By: Greg Cardinal
Greg,Do you have a photo of that leather cuff? My bungees also get chafed by getting pinched by the spruce "V" pieces during routine stretching during taxi, landing etc. Dan HelsperPuryear, TN -----Original Message-----
Greg,Do you have a photo of that leather cuff? My bungees also get chafed by getting pinched by the spruce "V" pieces during routine stretching during taxi, landing etc. Dan HelsperPuryear, TN -----Original Message-----
RE: Pietenpol-List: Re: Brake anti-rotation
Original Posted By: owner-pietenpol-list-server(at)matronics.com
Mine too! I find I have to replace the bungees every other year (and thisis the year)Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____
Mine too! I find I have to replace the bungees every other year (and thisis the year)Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____
Re: Pietenpol-List: Re: Brake anti-rotation
Original Posted By: helspersew(at)aol.com
Attached is a drawing of the anti chafe cuff.I purchased the leather from a local saddle shop. It was referred to as "sole leather" because it is relatively thick, about 1/8". It was very stiff but leather can be formed easily by soaking it in water for a few minutes.It is attached to the bottom of the ash block with a couple of small screws but the bungees keep it held in place.Round headed rivets per the original plans instead of threaded fasteners in this location would most likely eliminate the need for the leather cuff.Greg CardinalMinneapolis ----- Original Message -----
Attached is a drawing of the anti chafe cuff.I purchased the leather from a local saddle shop. It was referred to as "sole leather" because it is relatively thick, about 1/8". It was very stiff but leather can be formed easily by soaking it in water for a few minutes.It is attached to the bottom of the ash block with a couple of small screws but the bungees keep it held in place.Round headed rivets per the original plans instead of threaded fasteners in this location would most likely eliminate the need for the leather cuff.Greg CardinalMinneapolis ----- Original Message -----
RE: Pietenpol-List: Re: Brake anti-rotation
Original Posted By: owner-pietenpol-list-server(at)matronics.com
I LIKE it! Great idea, Greg. I'll do this when I replace the bungees onmine this April, during the Condition Inspection.Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____
I LIKE it! Great idea, Greg. I'll do this when I replace the bungees onmine this April, during the Condition Inspection.Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____
Re: Pietenpol-List: Rib Jig idea?
Original Posted By: helspersew(at)aol.com
My father and I have spruce on the way. I have a friend who has a cnc shop. Heis able to route out the the whole wing rib on a piece of plywood to where Ican basically just take all the pieces and inlay them in the routed plywood tobuild the rib. Does anybody see why this wouldn't work? He can also cut allthe rib pieces and all the gussets. Im kind of torn weather or not to have himcut all the rib pieces. By having him mass produce all the rib pieces and gussetsin say, 1 day. How much time would I be saving by having him make the piecesRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Re: Pietenpol-List: Rib Jig idea?
My father and I have spruce on the way. I have a friend who has a cnc shop. Heis able to route out the the whole wing rib on a piece of plywood to where Ican basically just take all the pieces and inlay them in the routed plywood tobuild the rib. Does anybody see why this wouldn't work? He can also cut allthe rib pieces and all the gussets. Im kind of torn weather or not to have himcut all the rib pieces. By having him mass produce all the rib pieces and gussetsin say, 1 day. How much time would I be saving by having him make the piecesRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Re: Pietenpol-List: Rib Jig idea?
Original Posted By: FandS_Piet
Disclaimer: If this is a prank from Mikey C. please disregard).Sir (don't know your name, please advise),Humbly asking: Are you sure you have chosen the right airplane to build? My advice to you is: No, do not have this individual cut all your rib pieces or rout-out your rib jig. I have three reasons for this. #1) It will be very difficult to keep the excess glue away from the routed-out plywood. If you were to use a traditional flat working surface, one can avoid this by laying wax paper or polyethylene sheet under the gluing surface.#2) You can almost bet that the pre-cut rib pieces will be wrong, and you will end up making them over again the old fashioned way anyway. This is custom work. Trying to make it into a mass-production operation at this point will almost surely be very frustrating and disappointing.#3) Why would you want to give up the experience of doing all these things yourself? Respectfully, if you are that hell-bent on speeding-up the process that much, you might want to slow yourself down at least to the point that you could ask your self whether or not you made the right choice on choosing the 80-year-old plans-built design in the first place. Sorry to be so blunt, but I see a disaster looming here. If time is of the essence, then maybe you might consider some of the other kits available on the market these days, such as Van's RV's or other similar kits? "Insert part A into part B" type of stuff. Building a Pietenpol is a journey, not a sprint. If one is worried about when the first flight will take place, then, respectfully, maybe that person should consider a different airplane. Not trying to discourage, but attempting to be realistic, maybe saving a lot of heart ache and expense.Dan HelsperPuryear, TN.-----Original Message-----
Disclaimer: If this is a prank from Mikey C. please disregard).Sir (don't know your name, please advise),Humbly asking: Are you sure you have chosen the right airplane to build? My advice to you is: No, do not have this individual cut all your rib pieces or rout-out your rib jig. I have three reasons for this. #1) It will be very difficult to keep the excess glue away from the routed-out plywood. If you were to use a traditional flat working surface, one can avoid this by laying wax paper or polyethylene sheet under the gluing surface.#2) You can almost bet that the pre-cut rib pieces will be wrong, and you will end up making them over again the old fashioned way anyway. This is custom work. Trying to make it into a mass-production operation at this point will almost surely be very frustrating and disappointing.#3) Why would you want to give up the experience of doing all these things yourself? Respectfully, if you are that hell-bent on speeding-up the process that much, you might want to slow yourself down at least to the point that you could ask your self whether or not you made the right choice on choosing the 80-year-old plans-built design in the first place. Sorry to be so blunt, but I see a disaster looming here. If time is of the essence, then maybe you might consider some of the other kits available on the market these days, such as Van's RV's or other similar kits? "Insert part A into part B" type of stuff. Building a Pietenpol is a journey, not a sprint. If one is worried about when the first flight will take place, then, respectfully, maybe that person should consider a different airplane. Not trying to discourage, but attempting to be realistic, maybe saving a lot of heart ache and expense.Dan HelsperPuryear, TN.-----Original Message-----
Re: Pietenpol-List: Rib Jig idea?
Original Posted By: "helspersew(at)aol.com"
Right on Dan. Shortcuts just will not work on a well designed airplane. Gardiner
Right on Dan. Shortcuts just will not work on a well designed airplane. Gardiner
Pietenpol-List: Rib Jig idea?
Original Posted By: airlion
Pietenpol-List: Re: Rib Jig idea?
Original Posted By: Rick Schreiber
I respect your answers and that is why I asked the question. I figured this isthe response I would get. One thing I don't I dont understand though is whilethis is a time saving proposition, how is this a shortcut that is looked atso far looked at as disgraceful. Dont get me wrong I am asking the question becauseI want the opinions of the those with the experience but I dont understandhow using a cnc machine to cut pieces allowing precision that cant be obtainedany other way is a disasterous shorcut. Im sure the rest of the responsewill talk me down of the ledge.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Sun, 08 Jan 2012 19:37:32 -0600
I respect your answers and that is why I asked the question. I figured this isthe response I would get. One thing I don't I dont understand though is whilethis is a time saving proposition, how is this a shortcut that is looked atso far looked at as disgraceful. Dont get me wrong I am asking the question becauseI want the opinions of the those with the experience but I dont understandhow using a cnc machine to cut pieces allowing precision that cant be obtainedany other way is a disasterous shorcut. Im sure the rest of the responsewill talk me down of the ledge.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Sun, 08 Jan 2012 19:37:32 -0600
Pietenpol-List: Re: Rib Jig idea?
Original Posted By: "dgaldrich"
Dan, I recognize your name in the Piet community and am thankful of your lengthy responseand opinion. Idon'tt want to give the wrong impression here that I amgoing to try and rush through the build and sacrifice quality. At the same timeI will not lie and say that I would rather our project take us 3-4 years asopposed to 5-6 years. To answer your question I believe we have definitelyy chosethe right airplane and cant wait to get started buildingRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Rib Jig idea?
Dan, I recognize your name in the Piet community and am thankful of your lengthy responseand opinion. Idon'tt want to give the wrong impression here that I amgoing to try and rush through the build and sacrifice quality. At the same timeI will not lie and say that I would rather our project take us 3-4 years asopposed to 5-6 years. To answer your question I believe we have definitelyy chosethe right airplane and cant wait to get started buildingRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Rib Jig idea?
Original Posted By: Dave Millikan
HiI'm going to be a little less blunt than Dan but he does make some good points.Oddly enough, the answers to your questions justify his point of view.First, rib jigs are easy enough to make and the process is sorta fun so you reallydon't save much time by having one CNCed. The plywood jig, as Dan said wouldbe a glue bucket. It would make an interesting wall plaque, though.Second, you CAN save a little bit of time by doing all the individual rib cap strippieces for each place on the mold at one time. I made a "master" set ofthe pieces for MY jig and then duplicated 30 some of them using a miter saw andstop blocks. Took maybe 30 minutes to make a pile of each of the pieces. Maybe2 days total to generate 12 piles of little pieces. You'd probably spendat least that amount of time doing all the programming for the CNC machine. Net saving -- zero. Net pride -- +1. That way, I could go out to the workshopeach night, take a rib out of the jig, "reload" the jig with new pieces, putgussets on the one fresh out of the jig to complete it and be back before Jeopardywas over. You can do two ribs per day at the most anyway so it's not whatyou call mass production.Third, and this really gets to the core of Dan's issue, you'll find out prettyquickly if you like the idea of doing a plans built airplane. If you find youactually like doing ribs, most of the other tasks involved in building a Pietenpolare a similar learning experience. The tasks become a little more complexand the materials, specifically steel and fabric, present their own challengesbut the skills are not difficult to learn and there are LOTS of resourcesavailable. Worst case is you find it isn't your cup of tea and it's time to look for a niceold Cherokee. (Mine, incidentally, is for sale) The cost for wood for theribs is a pretty small price to pay to find out you don't have the interest orwillingness to invest the time. You can always give the ribs to someone on thislist and keep one to hang on the wall.Best case is you get addicted to the idea of creating something with your own handsand come to Brodhead in a couple of years. You'll never know unless you try.Dave AldrichRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Sun, 8 Jan 2012 17:46:55 -0800 (PST)
HiI'm going to be a little less blunt than Dan but he does make some good points.Oddly enough, the answers to your questions justify his point of view.First, rib jigs are easy enough to make and the process is sorta fun so you reallydon't save much time by having one CNCed. The plywood jig, as Dan said wouldbe a glue bucket. It would make an interesting wall plaque, though.Second, you CAN save a little bit of time by doing all the individual rib cap strippieces for each place on the mold at one time. I made a "master" set ofthe pieces for MY jig and then duplicated 30 some of them using a miter saw andstop blocks. Took maybe 30 minutes to make a pile of each of the pieces. Maybe2 days total to generate 12 piles of little pieces. You'd probably spendat least that amount of time doing all the programming for the CNC machine. Net saving -- zero. Net pride -- +1. That way, I could go out to the workshopeach night, take a rib out of the jig, "reload" the jig with new pieces, putgussets on the one fresh out of the jig to complete it and be back before Jeopardywas over. You can do two ribs per day at the most anyway so it's not whatyou call mass production.Third, and this really gets to the core of Dan's issue, you'll find out prettyquickly if you like the idea of doing a plans built airplane. If you find youactually like doing ribs, most of the other tasks involved in building a Pietenpolare a similar learning experience. The tasks become a little more complexand the materials, specifically steel and fabric, present their own challengesbut the skills are not difficult to learn and there are LOTS of resourcesavailable. Worst case is you find it isn't your cup of tea and it's time to look for a niceold Cherokee. (Mine, incidentally, is for sale) The cost for wood for theribs is a pretty small price to pay to find out you don't have the interest orwillingness to invest the time. You can always give the ribs to someone on thislist and keep one to hang on the wall.Best case is you get addicted to the idea of creating something with your own handsand come to Brodhead in a couple of years. You'll never know unless you try.Dave AldrichRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Sun, 8 Jan 2012 17:46:55 -0800 (PST)
Pietenpol-List: Rib Jig idea?
Original Posted By: Rick Schreiber
RE: Pietenpol-List: Rib Jig idea?
Original Posted By: owner-pietenpol-list-server(at)matronics.com
I have to agree with Dan. For some reason, nearly everybody who startsbuilding a Pietenpol comes in with the idea that there is some way he/shecan "improve" the design or speed up the build process. Many decide thatwhat this airplane needs is for the plans to be done in CAD, either 2-D or3-D. Some try to automate the rib building process. Others decide that itis easier to make the fuselage oversize than to try and re-size themselves.As someone once said "You can modify the Pietenpol plans and build a goodairplane, or you can build it exactly to the plans and build a great one."I made a number of changes to the plans on mine, and most of them I regret.The Pietenpols I have flown that were built closest to the plans are thosethat fly the very best.It is GOOD to think about such modifications (to the design or the buildingprocess), but it is even better to not spend much time on them. Forexample, the ribs take 30 days to build - 1 rib per day. If you were to cutall the parts out ahead of time you can probably cut that down to 29 days.Unless you have multiple jigs, it still takes about a day for the glue tocure so you can pop the rib out of the jig. When I built mine, I would glueup a rib in the jig, and then cut out the parts for tomorrow's rib while itwas curing. The next day, I would pop the rig out, glue the gussets on theback side, put all the freshly cut pieces for the next rib in the jig andglue it up. Total working time per rib, about 3 hours. If all the partswere precut, it would save 2 hours of cutting parts each night while theprevious rib was curing. Total time saved would be zero because thelimiting factor is still jig time for curing the glue (note - I usedResorcinol, not T-88, so curing times may vary a bit).If you want your friend to cut a rib jig out of some material that is inertto epoxy, such as Delrin or ultra high molecular weight polyethylene, youcould use such a jig to advantage, as long as your shop is held at aconstant temperature. The nice thing about a wooden rib built in a woodenjig is that the linear coefficient of thermal expansion as well as theshrinkage or expansion with changes in humidity is the same between the woodof the rib and the jig. Not so for a plastic jig.Don't get discouraged by all this talk. Just get the plans, build your ribjig, and start making sawdust. BTW, if you haven't got them yet, buy thefour Tony Bingelis books (The Sportplane Builder, Sportplane ConstructionTechniques, Firewall Forward and Tony Bingelis on Engines), and READ them(they don't do you any good sitting unread on your bookshelf). You can getall four from the EAA for about $80, and just about any question you haveabout how to build an airplane can be found in the pages of those books.What is your name and where are you building your Pietenpol? If you notice,many of us that have flying Pietenpols list not only our name and location,but our N-Number so you can identify us by our airplanes at Brodhead. YouARE planning to visit Brodhead, aren't you? It is the best place to get anyPietenpol related question answered - usually several different ways.Welcome aboard and keep the List appraised of your progress.Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____
I have to agree with Dan. For some reason, nearly everybody who startsbuilding a Pietenpol comes in with the idea that there is some way he/shecan "improve" the design or speed up the build process. Many decide thatwhat this airplane needs is for the plans to be done in CAD, either 2-D or3-D. Some try to automate the rib building process. Others decide that itis easier to make the fuselage oversize than to try and re-size themselves.As someone once said "You can modify the Pietenpol plans and build a goodairplane, or you can build it exactly to the plans and build a great one."I made a number of changes to the plans on mine, and most of them I regret.The Pietenpols I have flown that were built closest to the plans are thosethat fly the very best.It is GOOD to think about such modifications (to the design or the buildingprocess), but it is even better to not spend much time on them. Forexample, the ribs take 30 days to build - 1 rib per day. If you were to cutall the parts out ahead of time you can probably cut that down to 29 days.Unless you have multiple jigs, it still takes about a day for the glue tocure so you can pop the rib out of the jig. When I built mine, I would glueup a rib in the jig, and then cut out the parts for tomorrow's rib while itwas curing. The next day, I would pop the rig out, glue the gussets on theback side, put all the freshly cut pieces for the next rib in the jig andglue it up. Total working time per rib, about 3 hours. If all the partswere precut, it would save 2 hours of cutting parts each night while theprevious rib was curing. Total time saved would be zero because thelimiting factor is still jig time for curing the glue (note - I usedResorcinol, not T-88, so curing times may vary a bit).If you want your friend to cut a rib jig out of some material that is inertto epoxy, such as Delrin or ultra high molecular weight polyethylene, youcould use such a jig to advantage, as long as your shop is held at aconstant temperature. The nice thing about a wooden rib built in a woodenjig is that the linear coefficient of thermal expansion as well as theshrinkage or expansion with changes in humidity is the same between the woodof the rib and the jig. Not so for a plastic jig.Don't get discouraged by all this talk. Just get the plans, build your ribjig, and start making sawdust. BTW, if you haven't got them yet, buy thefour Tony Bingelis books (The Sportplane Builder, Sportplane ConstructionTechniques, Firewall Forward and Tony Bingelis on Engines), and READ them(they don't do you any good sitting unread on your bookshelf). You can getall four from the EAA for about $80, and just about any question you haveabout how to build an airplane can be found in the pages of those books.What is your name and where are you building your Pietenpol? If you notice,many of us that have flying Pietenpols list not only our name and location,but our N-Number so you can identify us by our airplanes at Brodhead. YouARE planning to visit Brodhead, aren't you? It is the best place to get anyPietenpol related question answered - usually several different ways.Welcome aboard and keep the List appraised of your progress.Jack PhillipsNX899JPSmith Mountain Lake, Virginia _____
Pietenpol-List: Rib Jig idea?
Original Posted By: Michael Perez
Re: Pietenpol-List: Rib Jig idea?
Original Posted By: KM Heide CPO/FAAOP
My turn! If you want to use that ply contraption,great, but you will need to drill at least 2" holesunder every glue joint so the glue falls throughwithout touching anything. Also these holes will benecessary for popping the rib out of the jig.Now, having said that, personaly I would still usethe flat board covered in saran wrap with blocksand cams screwed to it. Why? Well, the excess gluethat does drip down hits the saran and flattens out.When you turn the rib over to gusset the other sideyou now have even more gluing surface than the firstside. Right? So what happens to that glue in yourfancy jig with holes in it? Why, it drips this big blob you have to cut off before glueing down that backside gusset! Trust me, you can clean away excess glueall you want but the next day there will still be a blob!Clifhttp://www.clifdawson.ca/Homepage4-10-06/Pietenpol.htmlPilots are a rare kind of human. They leave the ordinary surface of the world, to purify their soul in the sky, and they come down to earth, only after receiving the communion of the infinite." Jos=C3=A9 Maria Velasco Ibarra, President of Ecuador You asked about a CNC rib jig. I say, if you can get it to work, do it. As others eluded to, with out some homework and some thought, it can be a can of worms. But if you can make it duplicate ribs as drawn, great! Michael Perez Karetaker Aero www.karetakeraero.com ________________________________________________________________________________Date: Sun, 8 Jan 2012 20:33:07 -0800 (PST)
My turn!
If you want to use that ply contraption,great, but you will need to drill at least 2" holesunder every glue joint so the glue falls throughwithout touching anything. Also these holes will benecessary for popping the rib out of the jig.Now, having said that, personaly I would still usethe flat board covered in saran wrap with blocksand cams screwed to it. Why? Well, the excess gluethat does drip down hits the saran and flattens out.When you turn the rib over to gusset the other sideyou now have even more gluing surface than the firstside. Right? So what happens to that glue in yourfancy jig with holes in it? Why, it drips this big blob you have to cut off before glueing down that backside gusset! Trust me, you can clean away excess glueall you want but the next day there will still be a blob!Clifhttp://www.clifdawson.ca/Homepage4-10-06/Pietenpol.htmlPilots are a rare kind of human. They leave the ordinary surface of the world, to purify their soul in the sky, and they come down to earth, only after receiving the communion of the infinite." Jos=C3=A9 Maria Velasco Ibarra, President of Ecuador You asked about a CNC rib jig. I say, if you can get it to work, do it. As others eluded to, with out some homework and some thought, it can be a can of worms. But if you can make it duplicate ribs as drawn, great! Michael Perez Karetaker Aero www.karetakeraero.com ________________________________________________________________________________Date: Sun, 8 Jan 2012 20:33:07 -0800 (PST)