What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

2K Epoxy primer

Skeejere

Member
I'd like to prime my internal parts with my empannage build, but not sure I'm ready to go all in with a paint sprayer, larger compresser, paint booth, etc. Have also heard that products like AKZO can be pretty dangerous for the beginner. Anybody know of a specific brand of rattle can 2K Epoxy primer that I could use just for the empannage kit, and then maybe upgrade to the spray gun system later?
 
Do you actually mean a 2k aerosol epoxy primer? They exist but are rather expensive ($25-$30/can) and you only get a day or so once you pop and shake before you have to discard the can. And they won't be any safer than a sprayed 2k epoxy. You need the same basic PPE: gloves, respirator.

If you are just looking for an aerosol primer (1k), there are lots of options. SEM, Dupli-Color, Rustoleum tend to be the most commonly mentioned here. These are not epoxy and not catalyzed so they do not have the durability that a 2k epoxy does.
 
True 2K epoxy primer out of a rattle can will have the same chemical properties and associated risks as 2K epoxy primer out of a quart can and spraygun. After all, they are both two part epoxy aerosols.

But the rattle can version will be several times more expensive over the long run, and once you start one of the rattle cans, you have to consume all of it in that spray session, probably leading to wasted expen$ive primer.

So research and buy PPE, get a cheap Harbor Freight spray gun, and buy your primer in bulk. Whatever compressor you have in your shop will be adequate, if not ideal, for spraying parts.

But, if you must use rattle cans, here's one. I haven't used it, but Eastwood sells decent stuff:

https://www.eastwood.com/eastwood-s...MI7MCNt8eH6gIVlOeGCh1GQAFTEAQYASABEgJbyfD_BwE
 
Last edited:
Primer

2k epoxy is 2 parts A + B mixed together, once mixed it has a pot life, so it is not readily available in a rattle can.

Priming can be done with a cheap $20 spray gun and the same medium size compressor that will run a rivet gun. It doesn't need a paint booth, it can be done outside if you have a suitable outdoor area to work.

It is good to be health conscious and to wear a proper respirator with any volatile compounds.

Good luck and have fun!
 
Last edited:
2k epoxy is 2 parts A + B mixed together, once mixed it has a pot life, so it is not readily available in a rattle can.

The one I linked IS a true two part epoxy. It has a membrane inside the can that you break to mix the two parts before spraying. The downsides are expense and waste.
 
Kirker EnduroPrime

True 2K epoxy primer out of a rattle can will have the same chemical properties and associated risks as 2K epoxy primer out of a quart can and spraygun. After all, they are both a two part epoxy aerosols.

But the rattle can version will be several times more expensive over the long run, and once you start one of the rattle cans, you have to consume all of it in that spray session, probably leading to wasted expen$ive primer.

So research and buy PPE, get a cheap Harbor Freight spray gun, and buy your primer in bulk. Whatever compressor you have in your shop will be adequate, if not ideal, for spraying parts.

But, if you must use rattle cans, here's one. I haven't used it, but Eastwood sells decent stuff:

https://www.eastwood.com/eastwood-s...MI7MCNt8eH6gIVlOeGCh1GQAFTEAQYASABEgJbyfD_BwE

Interesting. I was told by Kirker tech support, Eastwood and Summit are rebranded Kirker paint. Kirker EnduroPrime is an epoxy 2K primer. Pretty tough stuff. Easy to mix and spray. Comes in white, gray and black. Had I not already sprayed my interior with SW Jet Flex, I would have shot Kirker EnduroPrime gray and black and left it as interior color. One paint. Easy to repair. Cheap.
https://www.autobodytoolmart.com/pr...m-epoxy-primer/kirker-automotive-paint-primer
 
Last edited:
I use PPG DP40 - Not cheap but awesome adhesion to aluminum.I believe lots of aircraft painters use that. Dilute it a little with acetone, wear a mask and spray outside. Epoxy stuff is nasty, same goes for Zinc Chromate.

Epoxy can/2prts are ok, Not worth it in my opinion, unless you use it once in your life. I have had gallons of epoxy primer last many many years, and are still great.
 
Over the course of my build I have used a few different primers. I prefer Akzo as do many other builders here on VAF. It is easy to spray, does require a respirator and is hard as nails when dry since it is a two part epoxy. You can buy a $10 gun at harbor freight right now that will do the job. It does have a bad smell so you need to have a mask.

I also have used SEM rattle can primer. It is pretty good for those types of primer. Its a little expensive but it works pretty well. It too smells bad and you should have a mask to spray it. It is pretty durable but lacquer thinner will take it right off. Akzo on the other hand can withstand lacquer thinner for some minor cleaning but it too will eventually come off but not easily.

I've tried Duplicolor primer that you can get from your autoparts store. In my opinion its not a good primer.

I've also tried Stewart Systems EKO prime. It is water based. I used it on my tail section and I wish I had used Akzo. It not very durable so it has gotten scratched up over time. If I knew how to strip it off easily I would do it and respray with Akzo.

So from all of this my recommendation is to just go with Azko. Yes it smells bad but it goes on easy, dries pretty quickly and it is very rugged stuff. You don't really think about this in the beginning but you will be dropping tools or having to clamp your primed surfaces during the build. Things will get scratched up but Azko is very durable and I have only minimal scratching on my Azko prepped surfaces.
 
If you are using a two part paint like PPG DP40 (which is what I use) a respirator is not enough. Read the data sheets. Buy a system like the Hobby Air with a full face mask. DP40 is a wonderful paint and is user friendly but it is POISON

Single part etching paints like the SEM brand are OK if you are not going to be scuffing on them with hands, feet, etc. They do not hold up to any solvents

Be safe with paints and solvents. Nasty stuff

Been flying my Cub again. Fun
 
I recently used the Eastwood rattle can epoxy primer on my new nose gear fork on my RV-12. I prepped it with PreKote, then sprayed the epoxy. The spray nozzle worked great. It is epoxy, so you need to take precautions when you spray it. The pot life is claimed to be 48 hours. I finished the color coats about 1.5 hours after spraying the primer.
I was replacing the nose gear and fork to comply with the recent service bulletin, so I did not need much primer. It is a little pricey, but it was convenient.
 
I'm surprised nobody stated the obvious: aluminum is in fact self-priming and you most likely don't really *need* to spray anything on the inside of your airplane. It will fly better and outlive you anyway. :D

The spray-can 2k epoxy primers typically contain isocyanates, which are neurotoxic just like cyanide. You'll want a fresh-air respirator, overalls and a massive air evacuation system if spraying indoors. A splitting headache means you got lucky.

The mix-it-yourself epoxy primers are much safer in this respect. The main danger is phenolic droplets curing inside your lungs. The Sherwin-Williams primer most folks use is self-etching too, meaning it will lift enough of the oxide without sanding to actually adhere to the underlying aluminum.
 
The spray-can 2k epoxy primers typically contain isocyanates, which are neurotoxic just like cyanide.

Are you sure about that? Here's a link to the MSDS library on the Eastwood site. When I looked up the grey primer, I didn't immediately identify any iso in it (I'm not a chemist, so YMMV). The item number for the grey rattle can 2k primer is 14149Z if anyone else wants to pull up the MSDS.

https://www.eastwood.com/sds-library
 
I do the little spraying I need outside, unless it's windy. Then I wait for the wind to quit. No booth required.

Wirejock mentioned Kirker EnduroPrime.

I've used SEM (like it), the rattle-can Eastwood epoxy primer (like it) and Stewart Systems Ekopoxy (like it, too). I plan to use the Ekopoxy for the interior.

Lots of options. But the BEST one is that where you are, you can leave the aluminum bare. However, I think it might be a good idea to spray SEM on the mating surfaces of any 6061-T6 to 2024, just in case dissimilar metal corrosion could occur. I expect that the risk is low but the prevention is not burdensome.

Dave
 
The Eastwood 2 part epoxy rattle can does contain isocyanates. It is in the hardener. The warning is on the can and the product information sheet shipped with the paint.
 
Back
Top