RE: 2X4 GASSER SPAD
Actually, the shaft is what holds my flywheel on. It is threaded onto the crank and that end has a "nut" shaped end to use a wrench. The other end(prop side) had a tapered square hole just smaller than 1/4 inch for the cable which was pressed into a square shape and it slid into that shaft. I just drilled it and tapped that square hole to use a 1/4-28 bolt. 40 cents for the (2)bolts and $1 for 2 washers and the welder I already had. The key is actually to have 2 bolts. 1 for the finished product and one(shorter) to hold on the washer so you can weld it in place. The hardest part is centering that washer as 1/4 washers holes are actually slightly larger so it floats a little on the bolt. If I had some shrink wrap I could have been a little more precise centering the washer before I welded it but it didn't hurt anything not to be perfect. I then just balanced as best I could and it works great. No bad vibes ( not that you can tell with these motors). I had an aluminum hub before and I just prefer a steel bolt and steel shaft. The bolt holds well so far. Plus it was so cheap and I designed it myself. What is more rewarding than that! The wing for this bird is unique as well. I think I am the only person using round PVC for a spar. A little heavier, yes, but what a symetrical wing it makes and is won't crack if you have a cart wheel landing or other mishap. It flexes just a little just like a full scale wing and glues to the coro great. The trick to using it though is you must close up the ends on the spar with foam or close the ends of the wings up. With them open at speed the thing sounds like an A-10 on a gun run. Cool yes but it resonates and makes the plane fly weird (cause premature aileron/wing flutter on a wing/airleron that wouldn't normally flutter) I have another SPAD that I had cracked the main yardstick spar(still flies though thanks to 4 MM coro holding it together)