Hi All,

I need some suggestions on how to drill the holes for Robart hinge points used in a flap application. In my installation, the leading edge of the flap is flat, so the hinge point must be placed near the bottom of the flap joint gap. I have seen this done before where the hinge point is approximately 90 degrees when the flap is fully up, and approaching straight when the flap is fully down. When done like this, just the hinge point "knuckle" is visible at the bottom of the flap joint gap.

Any suggestions?

Thanks!

John

Hey EZflyer. I needed to do the same so a made a drilling guide out of some wood and a brass tube. I was able to drill all the holes at the same angle. It worked out great. Taking a little time to create a jig was well worth it. I will try to take a pic of mine when I get home and send it to ya. Billy

I made a drawing of the hinge area, and made a drill guide from that.
I almost impressed myself when all the push-fit hinges lined up perfectly..
Be prepared that the hinges may come through the upper surface of the flap, if the section is thin.

Lars

the other option is using these type of flap hinges...

Here is the pic of the tool I made. Hope it helps are gives you an idea. The brass tube holds the bit securly so a clean hole can be grilled on an angle.

Hey Man:


Flaps with Robart hinges are easy to do, what I've done in the past to make this work is to bend the hinges over a 3/4 by 1/2 inch balsa strp and lightly tack the hinges down with CA. The strip will serve as a jig, and simulate the TE of the wing. Next, slide the flap onto the hinges so the the flap LE buts up to the jig (or simulated wing TE) and very very very lighty tack the hinges into the flap. Since the CA dosent flex, the hinges that are not 100% in-line will break free when you work the hinges. Also, since the hinges are mostly exposed they can be easily adjusted and re-guled until you are happy with the fit. Once you have them aligned and have removed the flap from the hinges, add little oil on the "knuckle" before you epoxy the hinges into the flap IOT keep the glue out of the joint.

This method is very simple and if I've made it seem over complicated let me know.

Good Luck
Scott