Marten Fabric Clips

[sbjmobil]

Has any one used Marten Clips instead of Rib Stitching on fabric on the wing's on a PA 22 .
I use them on a Aeronca 7 AC in the past and they worked out great. I've look at many Tri-Pacer in the past, but never seen any that had Marten Clips on them. They claim they have a STC for Al Piper Fabric airplanes. Any info on this would be appreciated.

Leo

[Gilbert Pierce]

I would think the Piper ribs are too flimsey to drill holes into for the clips. You could change the ribs to Univair at $50+ each and do it. That would require complete wing disassembly. I could stitch the ribs before you could get that done.
It would be easier to rib stitch the wings. Once you get going it takes about 45 minutes each if you do it by yourself. Quicker with help.

[Steve Pierce]

There is a Tri-Pacer here with them. The ribs look terrible with all the holes in them and I bet at recover there will be lots of cracked ones. They also have a lot of cracks in the paint where the clips are. The Piper ribs were not designed to have the cap strip pulled on. They are designed as a truss where the load pulls through the rib stitching to the opposite cap strip.

[Nathan Hiebert]

My PA-22 ribs had clips in them and there are many cracked ribs. After repairing/replacing all of them, I will be stitching them.

Nate

[Jason Gerard]

Factory piper truss ribs are Not designed for a tension load which is what your get when you use screws/rivets/martin wire. They are designed for a compression load which is what you get when you stitch the wings. If I pull a wing apart and the ribs have been screwed, riveted, or had martin clips in them those ribs are no longer airworthy and they get replaced. Rib stitching is easy and goes fast. No problem stitching a set of wings in one day by your self if you use the Staggering Beech knot.

If you don't want to stitch your wings buy a set of Univair ribs and sell you good factory Piper ribs. You can Pop Rivet Univair ribs. I can think of many people that would buy your factory ribs.


Jason

[Vagabondblues]

I attended Mr Babcocks piper rib rebuilding seminar at OSH this year. He said that there is an individual in Eau Claire, WI who is making the original cap strips. I lost the information that he gave us, so I am sorry to steal this thread, but I thought if you all are rebuilding ribs someone should know. Anyone know?

Todd

[sbjmobil]

Thanks for all the post's, I just did not know about the design of the piper rib ( I'm a better flyer than a builder) This is one of the great things about are web-stite, I could not have built my plane without this clubs info.
Needless to say I will be rib-stitching. If I can just learn to tied that darn knot.

Leo

[Gilbert Pierce]

Needless to say I will be rib-stitching. If I can just learn to tied that darn knot.

Leo

It is like learning to land an airplane. You will struggle for awhile then the light will come on and it will be easy.
Lay the Polyfiber manual or 43-13 page with the instructions/picture for tying the knot on the wing and follow each step. I made notes in mine to make it easier.
This helped me keep the parts seperate.
A: up from previous knot/hole and in back of the of the loop Part B
B: down and around the bottom of the rib-forms the front of the loop
C: up from the bottom. Never let go of this part until the knot is tight.

Hope this helps

[Nathan Hiebert]

If I pull a wing apart and the ribs have been screwed, riveted, or had martin clips in them those ribs are no longer airworthy and they get replaced. Rib stitching is easy and goes fast.

Jason

Well that is really disappointing...

[Jason Gerard]

Well that is really disappointing...

Sorry bud, a factory Piper truss rib full of holes all down the cap strips is not an airworthy part. I know, I hate to see factory ribs ruined like that too.


Jason