Brodhead Pietenpol Association

I am hoping that some of you builders have found an up dated method of connecting the crankshaft to the magneto. All I have are the early drawings on the original plans. There must be a better way with a better universal joint and magneto attachment. Can anyone give me an insight to how this is done. Has anyone constructed a brackett for magneto timing adjustment or does everyone follow the 1929 plans?

Don; there are plenty of Ford Model A engine builders and flyers out there, so I'm not sure why you haven't gotten any responses. My usual go-to source is Westcoastpiet.com and I just looked at a couple of likely candidates to see if there were any pictures of the magneto setup. One that most people have seen is Larry Williams' airplane, but there are no photos of his magneto setup on Westcoastpiet. Another is Dan Helsper's beautiful airplane, but no joy there either. Allen Rudolf, ditto. Thought I might have found something with N14143, the "Blitzkrieg Piet", but the photos of the engine have paper padding wrapped right around the location of the magneto coupling so no joy there either. Dennis Hall's airplane... close, but no cigar. Then I found one... Donald Stoval's setup. It appears to use either a Slick or a Bendix mag, and there isn't much detail, but it sure doesn't look like there's a piece of shoe leather being used as the coupling! http://westcoastpiet.com/images/Marvin% ... CT0083.JPG and http://westcoastpiet.com/images/Marvin% ... CT0060.JPG . I stopped my search when I got to Donald's, so you can continue on down the alphabetical list and I'll bet you'll find something useful.

Don, I just ran across your post on mag drives. I looked at the picture on the thread that was posted and it looks like the same drive used by Ken Perkins on his Piet with a model A. Ken made a "cup" that fits around a Continental o-470/io520 six cylinder engines mag drive cup. The cup holds two rubber pads that hold the lugs on an impulse coupling between them. When I work on Ken's engine next I'll take some pictures of the cup and pads for you.

Richard

I thank all for their input. I have talked with my magneto overhaul specialist and learned that a flexible aircraft coupling has been in use by several certificated airframe manufacturers for many years. He is overhauling my magneto and installing the coupling for me. The coupling will be installed on a very short shaft that is welded into the knurled cranking nut securing the water pump pully to the crankshaft. When all this is completed, I will take photos and write a short article for the newsletter. Cheers, Don Brewer