Did you dip? (rivets)

In my EAA Sportair workshop, one builder told me Boeing or Lockheed dipped (maybe sprayed?) their rivets in primer before riveting, while the other did not; I forget which. What have RVer?s done here? Did you use, primer, proseal or nothing at all?

Just trying to figure out what else I need to think about before starting my tail kit soon, and would appreciate any feedback.

Nope - not a one of them!

I actually thought about priming rivets as we were workign on buttoning up the belly skins on the RV-3 this evening - I couldn't imagine the tedium of adding that step to every rivet. But I know that some do!

Paul

Wow, I'm with Paul, and cannot imagine the extra work and time in priming individual rivets! Obviously, no I did not do this.

greg

Wet install for dissimilar hardware

At work (Raytheon) we typically specify a "wet installation" for steel hardware in aluminum structures. This involves dipping or brushing primer (TT-P-645) on bolts, threaded inserts, steel pulled rivets, etc. I don't recall ever seeing aluminum rivets dipped/coated prior to riveting aluminum structure. I would imagine such a structure would last a long time, though.

When I built the 2nd rudder for my -4, I put ProSeal on all the faying surfaces and was happy I only had the rudder to do!

Dean

The only times you would need to "dip" rivets is when riveting stainless with aluminum rivets. I did not dip the rivets for my firewall. However, there were a few stainless cherry rivets I used in the fuselage. I dipped them in primer. If you were riveting a pressurized aircraft, you would dip the rivets in sealant in some cases.

There's also the steel weldments. However, I'm not greatly worried as rivets come pre-treated and I don't believe installing them wet would improve matters that much. On the other hand, bolts get dipped; it is easy to scratch them when installing/uninstalling. I'm not sure what the forming process does to rivets but I've not heard of rampant failures due to rivet corrosion.

Thanks everybody. I still haven?t decided on what I?ll do, or for that matter what primer I?ll be going with yet. If I do this, I understand it has to be wet riveting, then, I suppose one wipes off the excess.

When I asked my instructor at the EAA SportAir about priming faying surfaces, he said not all do that as well. I was surprised by that, figuring this would be a good area for moisture to work in. I definitely want to do something here.

MDD

McDonnell Douglas and other manufacturers used pre-coated rivets.
Alodine or some special epoxy like stuff.

I believe so that they would not have to make a mess while installing them.

Your modern 2117 aluminum rivets are also coated, to help prevent corrosion of the rivet before installation. This is usually an alodine like substance.

I primed a bunch of rivets once. Then I realized I needed to get a life.

Bob Collins said:

I primed a bunch of rivets once. Then I realized I needed to get a life.

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My intention is to prime the rivets I use but only when they are locked in close formation. As for getting a life, I understand that there is a piece of grass somewhere in Wisconsin where intelligent life has been known meet once a year.

You have possibly 18,000 rivets to install. This will take lots of time. Unless you are trying to make your airplane last for ever, I don't think you will notice any corrosion problems with your rivets used as they come in the kit in your lifetime. You'll have enough other more important details to stress over during the build, that you don't need to worry about aluminum rivets in alcladed aluminum. Prime/corrosion proof the alloys and steel as suggested in the builders manual and enjoy your well built airplane. By the time it corrodes, if you're still alive (unlikely), there won't be any fuel left.

Scott Hersha said:

Unless you are trying to make your airplane last for ever, I don't think you will notice any corrosion problems with your rivets used as they come in the kit in your lifetime

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This is not true. Corrosion is dependent of the climate. If a piece of aluminum takes 200 years to corrode in a dry inland climate, it will take 1/2 to 1 year to start corroding in a coastal climate. These are typical factors, and can be better or worse dependent on specific weather conditions, pollution, storage (hangar, heated hangar, outside) etc etc.

This is related to priming and all the strange thing we find on the net about it. Typically it boils down to something nonsense like "priming is a personal choice, there is no correct or wrong way of doing it". The correct answer is that priming (for corrosion prevention) is 100% decided by the environment your airplane will be operating in. You may need nothing at all, or you may need the best. A typical example is Cessna 172 that was made in the US and at Reims in France during the 60s? and 70s. The ones imported from the US started corroding immediately in Europe, while the ones made at Reims (proper priming for European coastal and wet climate) lasts forever.

Uh okay here's what I really think. I spent many years along with thousands other's working for UAL grinding corrosion. That was on aircraft that were alclad, alodined, primed, painted, coated with LPS then Dynol, sometimes then sealed with wax and vapor barriers (in wet areas). And guess what we found after 4 years. MORE CORROSION! I have to say I have NEVER seen a rivet corrode. Maybe they do. If you really are worried about corrosion, fill a swimming pool with alodine, another with water and another with primer. Oh, then another with paint and another with Dynol (or corrosionX). Dip your plane in each. Of course you'll never be able to fly it because it''ll weigh 10,000 lbs. And yes, the evil corrosion will still find a way. Also, I never "dipped" any rivets at Boeing. Never seen one dipped. I think it's absurd.

Gen 3:19 "By the sweat of your brow, you will eat your food until you return to the ground, since from it you were taken; for dust you are and to dust you will return."