sswagerty

My Feedback: (53)

I am using robart hinge points on my Great Planes Extra. The installation went well until I noticed the gap between the trailing edge of the wing and the aileron. The gap is a little over 1/8 inch. It is too much. Should I cut an insert into the aileron or just live with it and cover the gap with monokote?
I appreciate your help in advance
steve

Flypaper 2

I cut into the aileron untill the hinge pivot point is lined up with the leading edge of the aileron and run it as close as you can without binding. Should have 1/32 to 1/16 of an inch.

majortom

If you have not glued your Robart hinges in yet, I would remove them and cut a small, square cut-out in each side--wing TE and aileron LE--tapered in to the hole, matching the taper on either side of the hinge hub. I use a micro-saw for the vertical cross-grain cuts and just the point of a #11 blade for the horizontal cuts. Actually I make these cuts first, giving me a flat spot to drill into for the hinge holes. A jab with a tapered punch will give you the perfect starting point for your drill bit.

I try to get contact along the entire hinge line between fixed & moving surface (both edges tapered, of course). I use just a drop of aliphatic in each hole, let it run down into the hole, both pieces at the same time, then press them together with the hinges in the middle. A fat drop down the hole will soak into the wood and get pushed to the bottom when you insert the hinge. If the glue is not runny enough to flow down the hole, a short length of pipe cleaner can be used to swab the glue down the hole. Don't use so much glue that it will squeeze out when you press the parts together. When you're glued up, flex the surface a few times to be sure your hinges are properly aligned.

As soon as the pieces have been pressed together, even though you would think the glue is still wet, I have been unable to pull the surfaces apart. So be sure you press the pieces tightly together right away, cuz that glue sets up quicker than you might think. Dry fit once or twice to be sure you're ready for glue.

If you've already glued, then a 1/8" gap will not be a major handicap. You can fly as is and probably notice nothing that bothers you. Or you can seal with monokote or gap-sealing tape for complete peace of mind.

Tall Paul

I dab a bit of white grease on the hinge where the two parts meet, before gluing...
Doing a better job mating the surfaces does help, though.

CafeenMan

Gaps are bad. I can't see what you're working on, but it may be better to just seal the gap with some Monokote and live with it.... lessons learned.

I love Hinge Points though, but you have to inset the pivot point into the control surface. You have to do the same thing with pinned flat hinges too.

I did a tutorial on Hinge Points you may want to look at.

http://www.airfieldmodels.com/inform...ints/index.htm