SuperSTOL flap smooth (or not so) movement

[Jamescham]

Hung my flaps yesterday. Right wing very smooth, extends easily and flap return spring retracts flap to non deployed position. Left side is not as much. Little harder to extend by hand and need to have about 1 or 2 pounds to retract. Before installing I sanded flap bracket smooth and polished with 320 grit sandpaper and a Dremel wheel. On each attach point(4) per flap there are 2 bushings and 4 nylon washers. Reamed inside of each bushing so bolt will fit thru the small one and smaller bushing will fit into the larger. I am going to polish each of the larger bushings that slide in the flap bracket. Wondering if bronze bushing should move freely in steel bushing( it was a press fit)?

[mac]

James - Worked on this for the past two days. I believe the bronze bushing is suppose to press into the SS roller/bushing. That said, when all torqued up, the roller needs to move freely around the AN-3 hardware. Easy to over tighten. When you do, the roller just slides/scrapes and the flap does not move down the track very cleanly.

I also found you have to make sure the flaps are moving down the tracks uniformly...........without bind. If you don't "square it up" at the top of the track, it won't move down smoothly.

I finally got both flaps moving very freely, with all the hardware, rigging, etc. in place, but it took 2 full days to figure it out. Lots of interference with skins, bolt heads, nuts, etc., that needed to be cleaned up to avoid sticking, binding, stoppage.

I'd recommend disconnecting all the rigging and just work on getting the flaps moving freely...............then slowly start making attachments to rod ends, adjusting turnbuckles, etc.

Finally, make sure your flap brackets are essentially the same distance off the trailing edge of the wing, at all four locations. I measured from the wing TE to the lowest point of the bracket. If they are different by much, flaps tend to hang up.

Now I need someone to tell me where the flap trailing edges should be? Flush with the bottom of the wing or up a degree or so? Or...........does it make that much difference??

[jak]

Put a straight edge under the wing and aileron rig ailerons flat and set flaps to meet ailerons. Jak