National Aeronca Association Bulletin Board

I would like to know if anyone has been successful in getting pop rivets approved to hold down the fabric covering. Thanx, Jim

Believe that the difference is in what style of ribs you are using. The pop rivets are not approved for use with the early style of Aeronca ribs.

JoeA

The pop rivets were substantiated in 1967 for ribs that are .032 inches thick, not .020 inch. Remember the screws only use a #44 hole and the pops need a #30 hole. Generally, its not an option for most guys before 1967...and was standard after that.

Contact:Cashmere Aviation, 925 Lower Sunnyslope Rd., Wenatchee, WA.
1-509-663-6851 or 782-3614. This is using 3/32" Marston Klick Rivets
under STC for wing ribs. Cost last reported was $75.00.
Best of luck

I don't know your intentions Jim, but if I can just mention a note. Pop rivets are great because they seem to go faster when assembling, but as I am finding out, they are a pain-in-the-butt when it comes time to recover/repair. I'm working on a set of Great Lakes wings that were assembled Completely with pop-rivets. A hangar door fell on the airplane, so i'm having to remove fabric and leading edges. By having to drill out the rivets, most of the holes have been elongated (do to poor installation, and me ). So now when I replace the leading edge, some holes and rivets will be larger than others. It's looking like about 1 out of 4 will be oversize. It may look funny having different size fasteners, but it's either that, or I oversize all of them. And if I oversize them all, what will happen in 20 years when it gets recovered?

So I'm wondering if screwe's really aren't a bad idea after all. Just what I'm seeing from experience.

Good Luck.

nkh

Thank you all, for your valuable information. I will use screws. Thanx, Jim

I'd probably use rib-stitch cord, myself.
unless there's something out there to make it illegal to do so.
To me rivits and screws would be a pain in the butt. I think that I could stitch 3 ribs in the length of time that it would take to drill one. and then stitch a few more in the length of time that it would take to install screws.

But I've got a question, Has anyone thought about clips? similar to those used on Cessna? I've seen them but never used them.

Martin clips are commonly used but they're about like pop-rivits, good and bad. The good side is it takes only an hour +/- to do a wing, which is really nice. But no lunch is free in aviation, the clips reek hell on the rib. When you remove them, the hole will often get damaged (elongated). Some have had problems with them in-between the holes with the wire lifting up and looking ugly under the fabric, but I suspect that was do to user error.

If you were making a living with your a/c in Alaska they would probably be a good thing. It would certainly cut down time when making repairs on a wing, or recovering. And the looks really don't matter when your haulling a 1000 lbs bloody moose out of a mud hole.

A guy told me it took him one day to cover the control surfaces on an AN-2 using the clips. He claimed it took only 10 minutes to clip one aileron!

nkh

Where can we get the screws? Spruce has discontinued the zinc screws. I also need a source for the nails. Thanks--BJ

I realize the pop rivet is not approved for pre 1967 ribs, but think about it. A screw, how mickey mouse can you get? The holes have to be perfect, and I'm sure after 10 recovers, and no overtightening the screws , all the holes are like new?? Ever look at how a screw works? One tiny angled section does all the work. I feel that if the factory had fabric rivets in the shelf, the would have used them, regardless of the rib thickness. I do not advocating the use of fabric rivets, but the logic for not approving them escapes me. There, I feel better now!
Ron

BJ,

AAR Cooper might have screwes, that is if there still in buisness. I haven't gotten anything from them in about 4 years since A/C Spruce is 6 miles away. Wick's sould have them aswell. As for nails, Wick's in St. Louis, Spruce or Cooper will have them. (If you've never used them, Wick's is a really good sorce for wood, both spar and ply's.)

Give'um hell Ron.

nkh

I just asked Aircraft Spruce if they had the #4 screws in zinc for screwing down the fabric on Aeronca Champs. They replied that they have them in stock, how many do you want? You might want to call them again.
I just finished rebuilding a Brand X airplane which was rib stitched. What a pain in the butt. Give me the screws anyday.
Just my humble opinion.

Having done both types of wings, I completely agree with Don. Will take screws anyday.

My other issue with ribstiching is that you really need two people to do it correctly and there is a lot of time that I am working alone.

Joe A

I have a report done by Larry Nelson where Champion approved the pop-rivets. Basically a series of pull tests. And the thinner ribs did not have the material to hold the pops adequately.

Basically, the Factory got sick of screws as well. Easy to over tighten, even before a plane was delivered it could have a few mangled screws. Tons of extra labor on top of that. Top it off with dissimilar metal corrosion.

Personally, I can imagine what a pain that and something like gas welding a frame would be. 1967 was a big year for production methods. MIG welding, spring gear, and pop rivets

It always log me in as Guest from my home PC.