Pre war ribs

[Larry Lyons]

OK I stripped the fabric off the wings of my T this weekend. The one that has been in a hanger tipped on her nose for 33 years. Not pretty! The urine from the pests living in the wing has ate away a lot of the leading edge and some of the nose ribs. The rest of the rib looks to be in good shape, so my question is; has anyone set up to make the T shaped alum. and bend new parts for the rib? My ribs already have pieces spliced in. The outside perimeter is not always one piece all the way around and at 50 to 70 bucks a rib I can make up some rib material. Any guidance here would be appreciated.
Larry

[astjp2]

Re: Pre war ribs

Univair has a repair kit that they use on the piper style ribs, that is what I had to use to make mine, I searched all across america to find good ribs, there are some out there but they are getting hard to find. I have not found a source for the originall roll formed material to make new ribs from. Maybe somebody knows where univair gets their material from. I do know that Cub Crafters are now using an extrusion for thier ribs now. I have one good rib left if someone would know how to make a pattern from it and we could find the materials, we could build our own...any thoughs out there? Tim

[VictorBravo]

Re: Pre war ribs

Although the original strips were made from a set of rollers (painstakingly designed by Arthur Taylor, CG's dad if I recall from Chet's book), I believe that people are missing an obvious solution...

Some fabricator correct me if I'm wrong... but the W sections can be made on a press brake without too much fuss.

The T sections can be made on a press brake into a hat section as a first step, then a steel T-shaped extrusion can be laid into that hat section and the sides bent up around that T-extrusion to form the T section.

Granted this is not efficient for producing thousands of feet of the rib sections, but it might be a lot less work than setting up a rolling machine!

ALSO, and again a knowledgable fabricator can correct me, but couldn't someone make a forming die out of nylon or Micarta blocks instead of rollers, and use O condition metal so the blocks don't wear out, and then heat treat the metal afterwards?

HELL, what about an extrusion with exactly the same cross section as the formed strips??? It ain't THAT expensive!

[Winston L.]

Re: Pre war ribs

You are welcome to use the jig I have when you are ready to assemble your ribs. I could also e-mail a picture of it if needed.


Winston

[Larry Lyons]

Re: Pre war ribs

What about this, I found it at McMaster-Carr. it is 6061-T6. Tough stuff.
Larry

T-Bars— Unpolished (Mill) Finish

Hardness: 80 Brinell

Yield Strength: 35,000 psi

T6 Temper

Conform to ASTM B221. Corners and edges are square. Thickness tolerance is ±0.006". Flatness tolerance is 0.006" per inch of width. Straightness tolerance is 0.050" per foot. Length tolerance is ± 1/4". Sold in 8-ft. lengths.

Base x Ht. x Thick. Each

5/8" x 1/2" x 1/20" 1668T16 $5.10

[Larry Lyons]

Re: Pre war ribs

Or this/ You would have to cut the back bone down is all. This is at Paramount Extrusions. The thickness is 0.050 by 1/2' wide by 1 and 1/4" tall. This is 6061 too.
Larry

ALUMINUM EXTRUSIONS
T-SECTIONS

"T" SECTIONS

DieNo. A B t R r1 r2 r3 Wt./Ft.
4517 0.500 1.250 0.050 0.010 0.010 0.010 0.010 0.102

[astjp2]

Re: Pre war ribs

Its close but it should only be 3/8" wide on top.....good thinking though Tim

[astjp2]

Re: Pre war ribs

I wonder if Dahlstrom Roll form would make the dies to manufacture them like the originals? Does anyone know the material? 3SO maybe? Tim

[Forrest Barber]

Re: Pre war ribs

Univair & Wag-Aero have the repair kits., a wee bit different try both maybe. Also you can replace the fabricated ribs with "stamped" ribs from the later ships, I have LOTS of nose ribs.... [email protected]

[Winston L.]

Re: Pre war ribs

The Dahlstrom company won't talk to you unless you order at a high volume. It is expensive for the to make the tooling.

Most of the stuff I talked to them about was steel so I don't even know if they do aluminum especially something that thin.

I would get that material from spruce or univair if I was doing that job.

Winston