Bevel for hinge

[jimmy bond]

Being new to flying and building the "if it looks right" approach is not ideal for me.got to the stage in a attila build where shaping is required and i do not know how much to round edges, TE/LE and TIPS etc. at the moment i do not know how much to bevel the ele hinge line.the plan looks like 45deg and very steep,that right?

also are robart??? hinges a good way to do for beginner? a hole seems less to go wrong that a slot.

[Dai Fledermaus]

If the two edges are rounded instead of having a chamfer, as the two edges try to roll around one another when the elevator moves up or down, it will try to pull the hinge out as the hinge line opens out and the whole thing starts to bind. Try it without fitting the hinges and you'll see what I mean. A chamfer of around 45 deg is about right. You could get away with less, it depends by how much you need the elevator to move.

Edited By Colin Ashman on 03/12/2013 09:49:01

[kc]

Rounding LE is not critical on something like the Attila. Aileron & elevator edges are often left square on many models. ( tapered but square TE )
A hinge slotting gadget is handy. Dubro or Sullivan brand I think, consists of a forked blade and a hooked blade to clear the waste and a centreing gadget. SLEC also do just the centreing gadget to use with a scalpel.
Either way experiment with trial slots in scrap balsa so you get it perfect in the actual model.

[stu knowles]

Robart Hinge points are good but only where the t/e is 1/2" thick. If fitting into your you will find that there's not much wood on either side of the hole.

Have to say that hinging control surfaces is my least favoured job of the whole build

stu k

[Bob Cotsford]

Hinge points probably require more accuracy in lining up the holes than when cutting slots for CA or flat plate hinges. Stu, I've used 1/8" hinge points in 1/4" surfaces without any issues as long as there's some depth to the trailing edge or a support block fitted, or an all sheet surface.

[Martin Whybrow]

+1 for what Bob said. If you're fitting them into ailerons made from TE stock, make sure you cut the hinges on the aileron side so the hole you need to drill doesn't break out of the surface.

Edited By Martin Whybrow on 03/12/2013 13:04:17

[Dave Miller]

I slot or drill these parts before assembly when they can be bound together to ensure alignment. I don't think that the bevel angle needs to be much more than the deflection angle of the control surface which is normally around 20 degrees.