Brodhead Pietenpol Association

Original Posted By: fishin
Question regarding aileron construction. Plans state "completely finish aileron before cutting free of wing". To me that implies:1. You build your 1/2" aileron beams in prior to cutting free. If so, the plans look like they have a 1/4" strip on the top and bottom of the beams to close the gap between the capstrips. This 1/4" strip is installed in sections between the capstrips and not one continuous strip the length of the beam? Otherwise, how can you only glue the first 1/4" of the capstrip to the beam?2. You must have the hinges you will use on hand in order to determine the gap you will need at the aileron attachment point. Trimming later won't be possible since it would require shaving the whole beam.3. There is no full size aileron horn pattern so the angle for the aileron beam must be determined by the horn dimensions and/or by setting the bottom of the aileron beam the required 1 1/4" aft of the wing aileron beam. Need to make sure that later building of the horn matches the beam angle or if I order them, I should get them before building ailerons.Is that a nod I hear???Thanks,Joe________________________________________________________________________________

Original Posted By: Larry Pasley
In a message dated 10/12/99 12:29:31 PM Central Daylight Time, jkrzes(at)hotmail.com writes:>The 1/4" X 1/4" strips, BETWEEN the rib capstrips, go on the aileron beams top & bottom to give the fabric a nice corner radius. After the ailerons are cut free, the butt ends of the capstrips and the 1/4"X1/4" filler strips should be finish sanded STRAIGHT with the gap and FLUSH with the surface of the wing, top & bottom>Bend, prefit, and drill the holes for the 3" barn door hinges (before the aileron is set free), and number them so, on final assembly, they will go where they were prefit for. When you bend these hinges, make a nice uniform radius of at least 1/8", so there will be no stress risers (small cracks) on the outside of the bends. The location of the bends should be exactly the same on all the hinges, so the centerline of the hinges all line up. Discard the aluminum pin that comes with the hinge, and use AN hardware for the hinge pin. I think it was a #8 machine screw that I used, with a long enough shank to go all the way through the hinge, then cut the threads off, and drilled for a 1/32" cotter pin. I also used AN cup washers under the heads of the flush screw heads, and countersunk them (slightly...by hand with a big drill bit) into the aileron beams, so the flange of the washer lays on top of the wood, to spread the load of the screw head. I also used cup washers (bigger size) under the heads of the aileron horn screws.>The bottom of the aileron beam is, as you said, set at 1 1/4", aft of the wing aileron beam. The plans built horn will match this angle. Before you rip this material (the 2 beams) on the table saw, make a few sample pieces, and prefit the cut angles. These angles and widths are kinda tricky, and must be uniform, and fit nicely to the rib capstrips.Enjoy the building process, take your time and do it right (no matter how many times it takes), and be proud of the finished product !!!Chuck GantzerWichita KSAviation Capital of the World________________________________________________________________________________

Original Posted By:> Joe Krzes [SMTP:jkrzes(at)hotmail.com]
Hi Joe,Your point # 1 is correct. The Beams are installed prior to cutting theaileron free. The capstrips are installed after the beams are in place.Note that simply attaching 1/2" x 1/4" capstrips doesn't work. Thecapstrips need bevels to match the angle of the beams and/or the contour ofthe ribs. If you are using piano hinges, the mounting screws may end up inthe seam between the capstrip and the beam, so use good glue and make astight a joint as possible.Your point # 2 is also correct. Piano hinges will result in the top of theaileron spar being closer to the beam in the wing than the original barndoor hinges. It's not much different, but it does vary enough that theangles are slightly different. The net result is a few degrees more ailerontravel (about 2 - 3 degrees).Point # 3 deserves some discussion. I used the aileron horn patterns asshown on the plans. I don't think the slight change in angle will affectanything. The only possible change is to the angle the aileron cables makewith respect to the wing spars, and again, the change is only a few degrees.I made my aileron pulley brackets to the plans and the cable angles areacceptable (they are not perfectly in line with the pulley, but they areclose enough). I think I kept the bottom distance to the aileron spar at1-1/4", and moved the top of the spar forward slightly to match the hingedimension. My piano hinges are flush with the top of the wing. BTW, I am installing piano hinges the full span of the aileron, in 12"sections. I originally only had two hinges per aileron, but as someone herepointed out, if one lets go, I've lost the aileron. I decided the extraweight would be more than made up for by increased safety and a sealed gap.Hope this helps. It is fun to be able to play with the ailerons on thecompleted wing. I've got mine rigged with string for the moment, and enjoymoving them and seeing how smoothly those piano hinges work.Jack Phillips> -----Original Message-----