Pietenpol-List: Vi Kapler's Plans?

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matronics
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Pietenpol-List: Vi Kapler's Plans?

Post by matronics »

Original Posted By: del magsam
HELP! Please. Let's see, it's been about ten hours or more by now. I'vespent the better part of the day going over the same thing and I'm going tobed leaving things where I started and with no place to pick up tomorrow.Can anyone tell me if Vi Kapler has an e-mail address or how his 3-piecewing plans differ from the one page wing supplement I have with his name onit dated 1975 and revised in March '82?I'm ready to order some wood, but I want to use it wisely, and not find outsometime in the future that I have to rebuild my ribs or come up with apatch job to make it work.I make precision woodworking tools everyday and work to tolerances of plusor minus .001. It can be a pain sometimes, but I'm starting to develop anattitude about working with drawings and numbers that are off by as much asa quarter inch. I've gone through a couple years worth of archived e-mailson wings, airfoils, ribs, and spars and an awful lot of remarks about "justbuild it to the plans or it's not a Pietenpol."Thanks in advance.MichaelGoing crazy in Portlandsylph(at)uswest.net________________________________________________________________________________Date: Sun, 14 Nov 1999 05:58:43 -0800 (PST)
matronics
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Joined: Sat Mar 18, 2017 8:29 am

Re: Pietenpol-List: Vi Kapler's Plans?

Post by matronics »

Original Posted By: del magsam
Thanks Del,I'll give Vi a call today.Personalizing one's very own airplane is inherent to the process ofhomebuilt aircraft, however, I'm more than a little surprised at the extentof personalization from the get go. I've designed a number of things in mywork experience, but never an airplane. Over the past six weeks or so, I'vespent in the neighborhood of a hundred hours of R&D work to find out that Ihave yet more to do before I actually start building.Believe me, my frustrations aren't with an aesthetic or personalized part ofthe plane, but with basics like wing ribs and spars. Just one example: thefull size rib drawing shows a vertical measurement near the center of bothfront and rear spars of 5 13/16". It's unclear as to what this measurementis for or if it is to the inside or outside of the top and bottom capstrips. Nevertheless, to get that measurement one would have to move thefront spar aft about 1 1/8" and the rear spar would have to be moved forwardnearly 8". Maybe I have a bad copy?In lofting my wing I've, not surprisingly, come up with a different set ofnumbers than those provided. Not much mind you, but different nonetheless.There are 21 verticals from the horizontal datum line with two dimensionseach that define the top and bottom airfoil surfaces. The shallow curves ofthe bottom camber can be lofted without one getting bent out of shape (punintended), but the top surface is another story: 11 of the 21 points weremodified from -1/64" to +1/16". It may appear to some of you that I'm overstressing thepoint here, but I've never built a wing before, and I'm counting on it tocarry me safely through the sky. What say ye experienced ones?Once this is behind me, I look forward to such personalized considerationsas type of engine, center wing section layout and use, interior (do opencockpit airplanes have interiors?), seats, instruments and controls. Mymain concern at the moment is that I build a sound airframe upon which thoseexpressions of personal taste can be confidently made. I trust my work, butI'm less sure when I have to modify a 70 year old wing. Am I really askingtoo much to get it right after 70 years? I don't think so.Ordering my Flyer and Glider Manuals today, and asking questions of thosewho've gone before. First wood order goes into Wicks tomorrow.Thanks,MichaelWinging it in Portland----- Original Message -----
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