I have lumps in the epoxy primer. The paint looks perfect until I start sanding it, then lumps start showing up under the surface. Some of them will sand out, some I can push them off with my fingernail, some of them I have to sand back down with 120 grit. I painted the cab of my truck three weeks ago and it has been sitting in a cold building. I have a binks #7 siphon feed which I had opened all of the way up, I usually do not do that, I dumped a lot of paint on the cab. I strained the epoxy after I mixed it. Cannot think of anything else I might have done wrong.
First your using two conflicting terms, you don't paint primer you spray primer or you prime a part. Epoxy primer if not shook properly especially when the primer is old will not mix. The solids stay clumped and are not Catalyzed so you must remove all the clumps.... You can not work over this! If you just bought the primer take it back and have them replace it with new product. And use a strainer with all products when mixing.
One more thing, all material that is catalyzed must stay at 70ﾟor higher for curing. I would not put it out in the cold for 48 hours or longer.
sounds like some kind of contamination also check the dates on the products how long has the hardener been open? any moisture filters or traps used?
Any chance that that paint froze in your building? If so there is your lumps. If you strained it is the only thing I can think of. You said you laid it on real good, I think that you might be better off with thin multiple coats and of course watching that your above 70°.
Why would saying painted primer or spraying primer cause this and if you read it he said he stained it Sent from my iPhone using The H.A.M.B. mobile app
Even though you strained it after mixing, the 2 parts may not have been totally blended. Well blended epoxy paint will be hard when cured and dust when sanded. Any unblended globules will be softer nuggets in the finished surface which will gum up your sandpaper.
I've sprayed thousands of gallons of epoxy in a industrial setting and product age is the biggest problem, two years from day of production is all PPG would give there epoxy ten years ago. What they do now?
Another tip/ Epoxy must be induced for a mininum of 20 minutes before straining, after it's mixed real well with the catalyst
True for most. I use Kirker and it requires no induction time. That, along with the 1:1 mix ratio, convinced me to try that brand..I like it. Works well and cheaper than most. OP, the lumps could be tiny water droplets from the air supply. Be sure that your air setup isn't causing that.
SPI is also a 1:1 ratio and an induction time is required. Don't know about Kiker as I never use bottom end products
Oh good! I thought my problem might be that I do not have a ‘cement’ floor! UGH! Think this project will be on hold for a while 9° tomorrow night! I keep it in the basement, so there is a least one thing that I did right. forever Do I use one, or do I use one that actually works? (not really I have a cheap water separator)
Not that I really know anything, but. When you get lumps like that either in the gun or on the sprayed surface it is usually the wrong activator or it was too old. At least that was what I was told at the Martin Senour factory when I was there for a little bit of training back in the late 80's
The hardener was left over from a 2017 purchase, mixed it with hardener from Sept 2018. I used the old hardener a couple of months ago, maybe it was mixing the two together that was the problem.
Any suggestions? 80 grit on the da is taking some of it off, going to be pretty hard go get it completely cleaned off. The paint is still pretty soft.
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