Fabric termination at rudder horn, large inspection panel

[svyolo]

I started the covering process with the trim tabs and rudder, which are the only 3 parts with protruding control horns. On the trim tab I used a couple of 1.5" square pieces of .020 with a slot cut for the horn around the horn to attach the fabric.

The rudder horn is a 90 degree bent piece of steel. One side has a hinge right next to it, which I used an aluminum strap like shown in the last Beartracks. I am not sure how to terminate the fabric at the horn. Glue the fabric to the horn?

Another question is large inspection covers. The small round ones are easy. The bigger one(s) needed at the tail I am wondering about. Won't the fabric tension pull them out of shape? Do you need to attach them somehow to the fuselage tubing to keep them in place?

Thanks for any help.

 

[jaredyates]

How large is the hole, and how thin are the rings?

 

[svyolo]

The elevator and trim horns need access. It looks like 10-12" long (vertical, or close) on at least one side of the fuselage, maybe both sides. Or maybe 2 smaller ones, one above the stab, and one below? I have seen pictures of both. Thickness of the frame? Not sure. I would guess at least .032 if the panel is big.

 

[Ed.Meyer]

We used .020 for the rectangular frames and only glued to the fabric. Frame was glued on after fabric attached to the structure and at least mostly shrunk. I don't recall dimensions but right side is larger that left and we wished we had made it a little larger. No problem with deformation. We used a single opening going above and below stab but .020 covers are necessarily two piece on each side. All worked out fine.

 

[stinger]

Svyolo , Not sure if this is what you are looking for but it worked for me . Stinger

 

[svyolo]

Stinger;
I have seen several others that did the inspection covers the same. It definitely doesn't look like there is a lot of room to deal with the trim and elevator horns. I was wanting to make bigger covers for that. Maybe I am wrong.

 

[zkelley2]

The previous owner did this very large panel below the elevator. Kinda nice. Easy to get your hands in there, safety wire things, etc. But he didn't leave an opening for the rudder horn so I had to add those.

 

[stinger]

Ok , I thought you was looking for a way to attach fabric at hinge areas . Stinger

 

[svyolo]

Can you tell what he did around the control horn for the rudder? The side opposite the bottom hinge is a 90 degree steel section. Just glue the fabric to the inside of that 90, or did he add some type of support from behind?

 

[rodsmith]

I made my access panel 8 1/2" by 7 1/2". It extends 3" above the longeron and provides good access. The frame is 3/4" wide .032. I cut my fabric around the horn and then installed a reinforcement piece that touches the horn but not glued to it. I don't think overlapping onto the horn would be a problem. I had welded a 3/8" tube behind the hinge to attach the fabric to.

 

[svyolo]

Thanks for the pics. I was going to do a similar cover for the elevator and trim.

 

[aerolite]

My frame's were 3/4" wide x .032 and covers were .025. I temporarily tape the frames to some tubing then after shrinking glue them to the fabric. The covers are one piece with a slot that slides over the tube. This leaves an opening behind the tube, but I covered it with a small piece of stick on mylar. It is covered when the tail parts are on and not noticeable. For the trim tab, I glued the frame onto the inside after shrinking the fabric, before closing up the other side. I don't have a pic of the rudder horns but I just glued the fabric to them, and cut the fabric around the hinge.

 

[svyolo]

Thanks. Those pics cleared up a few other things as well.

 

[zkelley2]

For the open edges, at least with oratex, you glue some kind of support there. A small strip of balsa wood or something like that is sufficient. No open seams.
Anywhere it doesn't move, it's glued to the steel.

 

[svyolo]

Yeah, used the aluminum straps like Mark G said now ship with the kits around the hinges. On the rudder horn I made up a 2 inch .020 plate that goes up into the corner of the rudder horn. Looks good on the one side of the rudder that is covered.