butt ribs

[jawinn]

I'm confused. I have pre-war wings and someone suggested I replace my butt ribs with the stamped variety. Both Taylorcraft and Univair list them as 5 pieces. I have a bunch of stamped ribs, to include some butt ribs, but only see 2 pieces. I have the full rib section with no holes for spars, and the 3/4 rib from trailing edge to the rear of the forward spar. What else is there? How does it go together?

[Ragwing nut]

Re: butt ribs

I'm confused. I have pre-war wings and someone suggested I replace my butt ribs with the stamped variety. Both Taylorcraft and Univair list them as 5 pieces. I have a bunch of stamped ribs, to include some butt ribs, but only see 2 pieces. I have the full rib section with no holes for spars, and the 3/4 rib from trailing edge to the rear of the forward spar. What else is there? How does it go together?

Full length outer that nails to the end of the spar, Inner rib trailing edge, inner rib center, inner rib nose, and I think they may include a diagonal support.

Mike

[Bobdog]

Re: butt ribs

My original '46 stamped ribs were just two pieces. The outer, which had no spar cutouts and the inner, which did have cut outs for the spars. The inner piece snapped into the outter piece, and was riveted together around the flange with flush rivets.

[Robert Lees]

Re: butt ribs

If I remember correctly, my stamped butt ribs were made up of two parts as Bob describes. At the front of this picture are the port & starbord inner pieces (with no nose rib). The outer pieces (i.e. those that go on the very end of the wing against the fuselage) have an integral nose rib, to which the aluminium leading edge attaches. This single piece of formed aluminium is 63" long!

Mine were screwed together, so forming a rudimentary but effective "box section" to resist the tensioning loads of the fabric.

I seem to recall that the truss-built butt rib is made of a lot more pieces, with braces to counteract the fabric tensioning loads

This picture shows the aperture for the rear spar fitting on the outermost half of the "box section"

[Ragwing nut]

Re: butt ribs

My original '46 stamped ribs were just two pieces. The outer, which had no spar cutouts and the inner, which did have cut outs for the spars. The inner piece snapped into the outter piece, and was riveted together around the flange with flush rivets.

My bad you are correct, the inner was originally 1 piece as well but over time they easy break. The prewar buttrib has a bunch of pieces to it. Basicly a standard long rib with a reinforcement top and bottom in the center part riveted to it. Then there are 4 diagonal braces in the center section and two to the rear. The braces can't be used if you want to run a wing tank so replace the early rib with a postwar when recovering an early wing.

Mike

[jawinn]

Re: butt ribs

Thanks for the quick replies. I have wing tanks for both wings and plan to use them, so out come the pre-war ribs...they'll repair some other boo-boos nicely.

[Larry Lyons]

Re: butt ribs

My pre-war built up butt ribs are a mess, with both having been repaired 4 (four!) times! Right where the spar passes through the web (top hat section) had failed both top and bottom. Now I need to make a 5th repair, in the nose to both, I do not want to do that. Anybody here have two, complete, repairable butt ribs they would part with. I have one wing tank and that butt rib is a mess with the repairs and being pulled out of shape by the covering, etc. I would really like to just go with the newer style butt rib. Larry

[pete]

Re: butt ribs

The Univair 5 piece butt ribs are a L&R tail rib, a L&R center rib, and one nose rib.
Pete

[VictorBravo]

Re: butt ribs

Thanks for the quick replies. I have wing tanks for both wings and plan to use them, so out come the pre-war ribs...they'll repair some other boo-boos nicely.

Be careful about the clearance for the fuel tank outlet versus the root ribs and the upper door frame on the fuselage. I actually had to grind away some of the fuselage door frame to allow the fuel line fitting to be installed into the tank. Some pre-measuring and a dry-run alignment test before the final wing installation would have prevented this problem, or at least allowed me to do the grinding at an easier time.

[Buell Powell]

Re: butt ribs

Hi Larry,
I think I may be able to help you find some ribs if you still need them. If you want- send me a PM and I will see if I can help.
Buell

[Larry Lyons]

Re: butt ribs

Hi Larry,
I think I may be able to help you find some ribs if you still need them. If you want- send me a PM and I will see if I can help.
Buell

Done, Thanks Buell. Larry