Brodhead Pietenpol Association

Original Posted By: "Christian Bobka"
Ten of the twelve British Pietenpols that have been finished and flown use abuilt up spar drawn by Jim Wills. There are 50 or so other underconstruction and they're doing the same. It's approved by the PFA - that'sour version of the EAA - who oversee homebuilts here in the UK and who areresponsible to the CAA - so it's gotta be tough! The front spar comprisestop and bottom spar caps each 1-1/4" x 7/8" with a 1/8" ply web. Sprucefillers and ply doublers are positioned at each rib. Longer spruce blocksand ply doublers are also used at the root and lift strut points. The rearspar is built the same way but the caps are lighter - 7/8" x 3/4". I believethis results in lighter and stronger spars than routed solid versions, andit's less expensive. Aircraft quality spruce is rarer than hen's teeth overhere! Another advantage is that it enables the all up weight to be increasedto 1200lb. I hope this information helps.Regard to everyone that side of the pond and thanks for giving us such awonderful flying machine.Alan James (G-BUCO)----- Original Message -----

Original Posted By: "Robert Haines"
George, About ripping cap strips, the following was sent to me from MontyGraves on the Ragwing list, this is about saw blades and might answer yourquestion. I'll cut & paste it.I will offer one other tip on table saw use, then I will shut for awhile. Ifyou use a fairly good 7.25 inch HOLLOW GROUND PLANER blade (about $10) onyour/any table saw to rip boards for the airplane projects. It TOTALTYenlimates sanding/planing/jointing.. They are avaiable at any good hardwarestore... yes the 7.25 inch blades work on 10 inch table saws... they make 6inch and 10 inch blades too, but the 7.25 are cheaper.. I love these blades,use a fairly slow feed, you will love the results, compared to a rip ormulti cross cut blade Of course 3/4 stock is easier to rip than 1.5 inch butyou can do both.. fairly easy. The other good thing about the planer bladeis it is narrower, less wasted high dollar material. Just slip a smal woodwedge in the slot cut by the blade as the cut is being made, to stop thevery narrow blade from binding.. And I would also like to get the plans for the UK spars, if available.Have fun!KentEagerly awaiting plans :)________________________________________________________________________________

Original Posted By:> "George Allen"
I am also interested in seeing the drawings for the British wing spar. Ihave questions like, how far do you let the web in the capstrips and whatdoes a splice joint look like. Someone PLEASE scan the drawing and emailit, I would be happy to put it on my web page.To help out with this topic, check out the NACA report:http://naca.larc.nasa.gov/reports/1920/ ... .pdfRobert HainesMurphysboro, IllinoisP.S. - George, as far as using a plane, I would if you had rough-cut lumber(the rough saw marks that come from the sawmill). I would also consider itif you are using a bandsaw (don't use a bandsaw, that's too much work). Butif you have a decent blade in your tablesaw, just sand it. I would alsosuggest using fingerboards with the tablesaw to keep the piece against thefence, they assure that you get a consistantly dimensioned cut and keep youfrom gouging the board if you bump it into the blade.