[] I am putting together a funtanaS 90 ARF and in the manual it says to seal the aileron and elevator hinge gaps. I have no idea what they are talking about. I built a Super Sky Bolt from a kit and didn't need to do this, what are they talking about? can some one help me?

thank

backyard flyer

put some monokote or clear packing tape or the like at the hidge gap. becuase of the huge throw one put on them, it it for 3d'' the tape help with the slop and redueces the chance of flutter

Sealing the hinge gap means to take a strip of covering about 3/4" - 1" wide and as long as the surface. Fold the strip in half WIDTH WISE. Flex the control surface as far as it will go and insert the folded strip in the opening. Using a TRIM IRON, iron 1/2 of the strip to the control surface and the other half to the main part of the structure (trailing edge of the main wing ).

The purpose of sealing the gap is to prevent air from getting in the gap and causing flutter.

FWIW - I have found that for regular sport flying, unless the gap is really large (over 3/32" ) you don't need to seal it. If the gap is large OR you will be doing ANY high speed flying, you should seal it.

What they are talking about it using covering material (monokote or ultracoat) to seal the gap so that air cannot escape through the gap. (see first diagram) IMHO this is probably the one best thing you can do to improve perfomance on any plane. It's not difficult to do at all. First cut a strip of covering material and fold it in half. A small trim iron is best suited for this but a regular covering iron will work, it's just a bit more cumbersome. Use a piece or two of masking tape to hold the aileron at full deflection so that the gap is wide open. Now use a trim iron to seal down the covering to one side of the gap. Then do the other side. see diagram

Hope this helps

Ken