>Setting up the ailerons to give the specified deflections is not always as easy
>as it should be. I have known occasions where it was impossible.
>It might be thought that the position of the drive pin is the main critical
>criterion. In fact it is it's relationship with the hinge pin that is crucial
>because this determines the radius of the drive pin's locus, and therefore the
>angle the aileron deflects for a given movement of the push rod. The plans
>unfortunately don't specify this dimension, WHICH NEEDS TO BE ACCURATE TO 1/64"
>or less, relying instead on all the other dimensions being accurate. IMHO you
>will save yourself hours of frustration if when you finally fit the hinges to
>your ailerons you make up a simple jig, which need only be two holes in a small
>aluminium plate, a 1/4" hole for the pin and a 3/32" one for the hinge pin. I
>guess Andy's CAD might be able to tell us the distance between the hole
centres.
>A pencil line on the plate should be added to align the bottom surface of the
>aileron.
>
>If you have not yet fitted the hinges you might like to do it this way.
> Mount the hinges on your straight edge as described in the plans. Leave the
>inboard hinge pin protruding 1/8" or so (unbent). Now flox the hinges to the
>aileron, again as per plans but drop your jig over the pin and the AN4
bolt. Use
>skin pins (rather than Clecos) to hold the hinges in place but don't
overtighten
>so as to avoid distorting the flanges. Allow to cure thoroughly before
>rivetting. This way you will end up with the two ailerons working together
>instead of fighting.
>
>If you've already finished your ailerons it would be well worth making the jig
>to fit one and using it to check the other. If they don't match decide
which one
>to alter and fix it. Easiest probably to move the hinge, but bear in mind you
>don't want to cause misalignment of the other hinge.
>
>Believe me, 1/16" discrepancy is too much {{8-<)
>
>Graham
>
> It's quite likely that the main reason for difficulty is a difference in the
>position of the hinge and drive pin is not identical in bothtwo ailerons
The latest issue of the manual does show a dimension from the AN4-10A bolt
to the edge of the aileron hinge flange. This dimension is 1.375". The
distance to the hinge pin will be effectively the same since the flange is
cut back locally to allow the hinge pin to lie on the line of the edge of
the flange.
It is quite correct that it is very important to get the distance the same
on both ailerons, and a simple jig as described above is a good way of
achieving this.
Roger
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