Original Posted By: Dan Yocum
I'm ready to make my wing rib jig and would like to use the 1:1 print that we orderedwith the plans. I would like to take a razor, cut it out, and then tracearound it for the jig. However I got to looking at the plans and then I startedtaking measurements on the 1:1 drawing, and it does not seem to match. Should i not worry about it?Should i draw the rib on my jig, as per the plans?ThanksRead this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Sun, 13 Nov 2011 22:05:48 -0600
Pietenpol-List: Wing rib profile questions
RE: Pietenpol-List: Wing rib profile questions
Original Posted By: owner-pietenpol-list-server(at)matronics.com
I labored over this same issue for weeks. I lofted the measurements, tracedexisting ribs from other builders and compared with the full-size prints.The differences were very small. In the end, I averaged the lofted drawingand full size print. If I remember correctly the difference was mostpronounced in the top front of the airfoil. It's one of those times in theprocess you just need to make your decision and get going.JackDSMN1929T-----Original Message-----
I labored over this same issue for weeks. I lofted the measurements, tracedexisting ribs from other builders and compared with the full-size prints.The differences were very small. In the end, I averaged the lofted drawingand full size print. If I remember correctly the difference was mostpronounced in the top front of the airfoil. It's one of those times in theprocess you just need to make your decision and get going.JackDSMN1929T-----Original Message-----
Pietenpol-List: Re: Wing rib profile questions
Original Posted By: "j_dunavin"
Is the difference consist at every measurement? If so, then your rib plan needsto be proportionally resized. You can go to any Kinko's/Fedex Office, and theycan do it. Simply ask them to reprint your plan at 102%, 105%, 107% or whateverit needs to be.Or do like Jack says, live with the small difference, and build on.--------Semper Fi,Terry HandRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Wing rib profile questions
Is the difference consist at every measurement? If so, then your rib plan needsto be proportionally resized. You can go to any Kinko's/Fedex Office, and theycan do it. Simply ask them to reprint your plan at 102%, 105%, 107% or whateverit needs to be.Or do like Jack says, live with the small difference, and build on.--------Semper Fi,Terry HandRead this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Wing rib profile questions
Pietenpol-List: Re: Wing rib profile questions
Original Posted By: "Bill Church"
No, Jack is right. Most of the difference is in the front of the wing, and it issmall differences. I think that I will draw out the wing in Auto Cad, and then place the two sideby side and see what gives.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Wing rib profile questions
No, Jack is right. Most of the difference is in the front of the wing, and it issmall differences. I think that I will draw out the wing in Auto Cad, and then place the two sideby side and see what gives.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ___Subject: Pietenpol-List: Re: Wing rib profile questions
Original Posted By: Michael Perez
If you're comfortable with a pencil and ruler and a square, it only takes aboutan hour to loft the rib plan onto a nice flat piece of wood (I used MDF, butgood quality plywood will work as well).If you're not so handy at drafting, before deciding to just "live with the smalldifference", the most important dimension to check on your full size rib plotis the spar-to-spar dimension.If using the full-size plot, why would you want to cut out the rib profile witha razor? Just leave it as is, and use spray adhesive to glue the whole plot tothe board, then add positioning blocks on top of the paper, as needed. If youcut the plan into a narrow strip of paper, you are more likely to end up withdistortions in the rib profile, since a long narrow strip of paper is less stablethan a wider strip.Bill C.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Mon, 14 Nov 2011 07:15:33 -0800 (PST)
If you're comfortable with a pencil and ruler and a square, it only takes aboutan hour to loft the rib plan onto a nice flat piece of wood (I used MDF, butgood quality plywood will work as well).If you're not so handy at drafting, before deciding to just "live with the smalldifference", the most important dimension to check on your full size rib plotis the spar-to-spar dimension.If using the full-size plot, why would you want to cut out the rib profile witha razor? Just leave it as is, and use spray adhesive to glue the whole plot tothe board, then add positioning blocks on top of the paper, as needed. If youcut the plan into a narrow strip of paper, you are more likely to end up withdistortions in the rib profile, since a long narrow strip of paper is less stablethan a wider strip.Bill C.Read this topic online here:http://forums.matronics.com/viewtopic.p ... ______Date: Mon, 14 Nov 2011 07:15:33 -0800 (PST)
Pietenpol-List: Re: Wing rib question
Original Posted By: "Don Emch"
Subject: Pietenpol-List: Re: UndercamberI agree with ________________________________________________________________________________Subject: Pietenpol-List: Re: Wing rib question
Subject: Pietenpol-List: Re: UndercamberI agree with ________________________________________________________________________________Subject: Pietenpol-List: Re: Wing rib question
Original Posted By: Woodflier(at)aol.com
Gene... can't agree with you more. Just like any other wing. The rib stitchingwill pull it in. Totally a non issue. The undercamber is a key to its lowspeed characteristics. Same reason the Aeroncas and many others have a very slightundercamber. Don EmchNX899DERead this topic online here:http://forums.matronics.com/viewtopic.p ... __________
Gene... can't agree with you more. Just like any other wing. The rib stitchingwill pull it in. Totally a non issue. The undercamber is a key to its lowspeed characteristics. Same reason the Aeroncas and many others have a very slightundercamber. Don EmchNX899DERead this topic online here:http://forums.matronics.com/viewtopic.p ... __________