I am taking off a bay on each wing of my 4*40. Doing this takes off the last hinge. How the distance from the next hinge to the tip is 4 3/4 inches. Do I need to add a hinge at the end?

Only if you want your aileron to stay on.

Why would I want that

I didn't mean to be a smart*****, but sometimes I just can't help myself (The voices get angry when I don't listen to them)

But 4 3/4" is a bit much to have hanging off the end. Something you could do to make things easy is to just use a "covering hinge" on the end.

So if i sealed the gap it should be ok?? I think I can get a hinge in there if I have to.

Sealing the gap will help, but a proper covering hinge would be better. To make a covering hinge, cut 6 strips of covering ( About 3/8" x 1" ) and seal two of them together sticky side to sticky side with about a 1/4" overlap. Then weave them through the gap and iron them down (See pic)

Thanks Minn. Your pics are always the best. I did manage to get a ca hinge in there though. Thanks

Oh, ok, Cool!

I'm a big fan of lots of hinges. As far as I'm concerned the two most important hinges are the one nearest the control horn (right under it preferably) and the one nearest the tip. I like them spaced no more than about 4" apart. I've installed as many as 9 or 10 hinges in a control surface at times.

Glad you got yours worked out, but please never take chances with stuff like this. If you're questioning it in the first place, then you probably already know it's a problem.