Pre-war Rib Repair

[VictorBravo]

This may have already been addressed...but :

I understand that a lot of older Piper aircraft have the same type of truss ribs as a pre-war Taylorcraft, using the formed aluminum T shaped rib material. This does not surprise me considering that CG designed them both. I actually had a 47 metal spar J-3 Cub, that had those ribs drilled for Martin Wire! Yuck!

Since pre-war Taylorcraft rib repair kits may not be available at the local Wal-Mart these days, has anyone used the Piper material to repair Taylorcraft ribs? Does it fit correctly?

I have seen the generic repair method in AC 43-13, but it looks like it might not be as easy to do it that way and have it look right.

I am in the fabric stage of my repair, and I made the decision to leave the previous sloppy rib repairs and other stuff alone for now just to get flying again. Some sunny day in the future, I might re-cover the wings and want to do a proper repair/restoration.

I absolutely do not want to hoard pre-war ribs or buy up what I can find, since that would take parts off the market and harm the REAL antique restorers who build champion airplanes.

So, I'd like to know if the Piper material has been successfully used to repair T-craft truss ribs. Or if there is a better, cleaner way to do it.

Bill

[lktiller]

Re: Pre-war Rib Repair

easy enough to do. quick description. carefully grind/drill out any rivets in the way. Cut out the bent/broken/corroded cap strip back to good stock. Smooth the cut ends.
cut the 'T' stock 3 inches longer than the cut out piece. Gently open the end of the new stock and slip it over the old rib cap, 1 1/2 inches each end. Reform the new stock to a snug fit over the old. I build a clamp arrangement to fit over the cap & squeeze it to shape.
rivet the tail of the 'T' - minimum 4 rivets each joint. All is a close fit. I modified the dies in a rivet squeeze tool.
In areas where the rib cap curves, it easy enough to crimp the webbing as you form the cap strip around the curve. It is critical that the curve on the nose rib is maintained. If one stands out more than others the leading edge sheeting will not fit. Small, undersize bends can be corrected by laying an extra layer of chaffing tape on before placing the leading edge sheet.

For the bridge bracing pieces, simply cut to length & shape, rivet in place. The brace stock is about 1/16 wider than original. don't splice it. replace broken pieces.

To build complete ribs or nose ribs requires a jig. Again easy enough to do.

[Forrest Barber]

Re: Pre-war Rib Repair

bless you for a very good description. Taylorcraft & Piper used to sell a repair kit , if the rib is not too bad you can put flat stock maybe .032 about twice the size of the lower flange and about 4 inches long up into the broken part and rivet it in place this will act as a repair and work good too.