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everything was sanded with 180 then washed with water and wiped with acetone...

CatfishHunter wrote: ↑Wed Feb 12, 2020 1:41 pm everything was sanded with 180 then washed with water and wiped with acetone...

Acetone..no.

Use denatured alcohol.

I don't believe acetone would be advised by any manufacturer.

Stick with more inert solvents for general cleaning or use the advised wash.

Acetone can even solve the rag you use, for example, and leave a residue.

My guess is that this is the culprit. A lot of people may argue with me and say acetone will flash, but I do NOT trust putting this solvent on AND I waited a whole day to let alcohol flash off fully. Then I tack twice; once day of paint. I had very little trouble with contamination, but it was not easy. We had to drive up the humidity to about 50% for tack cloths to not build static.

Then on our final coat, I had some dried paint in the first go; so annoying. It is gonna be in there until a repaint now!

I did some further reading and acetone leaves behind a trace 1/1000th of 1% and it is not inert.

Pretty sure the acetone or acetone in pinholes or something solved your top paint.

Cured epoxy primer is darn tough stuff.

could have been the acetone but never really had an issue with it before, but i have been rushing this last month or two to get on the water before this winters fishing season ends... I chalk it off to be a lesson learned and be sure to take my time and follow the instructions exactly when i get time to redo it, but doubt i'll be using that totalboat paint. it was very thick from the get go and didnt want to thin very well with their "special brushing thinner" I knew from the first coat something was up with the paint, as it took forever to cure. it's a shame because the color is great and very glossy.

I assisted in spraying a friends boat with awlgrip. We cleaned the boat with fresh cotton rags and the Awl-Prep Surface Cleaner and then a tack rag exactly as described in their manual. The first few coats are barely a mist, but you could tell the paint was almost beading up. We made the call to clean off the paint before it cured which was not a fun job. Many paper towels a a lot of denatured alcohol later, we wiped down the boat again this time still using the denatured. Paint job went off without a hitch that time.

Point being we did everything by the book and there was still some contamination either on our rags or in the solvent that came straight from the manufacturer. I'd try again with a different solvent, different rags, and a different batch of paint. Painting is a pretty sensitive process.

thanks guys, i will definitely use denatured alcohol from now on. and now that you mention it i was having trouble with the rags linting up the surface and had t buy some different ones during the last part of the build. it doesn't help that my build is under an outdoor carport. I'll try to get through the next few weeks of fishing and take care of this asap. I scuffed up and repainted the loose areas earlier to get me through as long as possible fingers crossed.

Sorry to hear about your paint issue, that sucks. The same thing happened to me 13 years ago.
I don’t have confidence in acetone either. I believe it could have affected your paint bond to the primer. You have gotten great advice on that.
I’m also not a fan of mineral spirits for cleaning paint brushes. After my first paint debacle, I throw the brush away after each coat.
I also would go rougher than 180 grit when you are putting 1 part type paint on top of 2 part primer. I’d use 120 grit myself, for more tooth.
The problem with 180 grit paper or a disk is it that the abrasive turns into 240 or 320 grit after a few strokes or a minute or two with a sander.
We fight this issue a lot in my woodworking plant, trying to balance stain penetration and finish quality with sanding processes.

Another wild guess is humididity. Or drying too fast.

Good luck catfish. Painting is finicky business. A paint that goes on thick is also bad cuz a high mil can also peel.

I hope mine works out.

I'm going to guess more the acetone than anything else. A good majority of the acetone sold in big box stores is recovered acetone from hazardous waste operations, or so I've been told by a couple of vendors. That stuff has more "allowable" contaminants in it then the stuff from a scientific vendor which is rated out at 99.95-99.99 and the price reflects that. 4 liters or roughly 1 gallon is ~119 versus ~16 at big box stores.

Denatured alcohol is a lot easier to reprocess with fewer contaminants.