"Krylon primer on resin disaster" Topic

I used Krylon for the primer on some resin tanks. I washed the models with soap, left them to dry a few days, primed, and left the primer to dry a few more days.
Last night I used Model Master enamel paint with Testors enamel thinner.

Shortly after spraying on a light coat of the paint the primer began to lose its bond and bump up. It looks like I had some reaction. It only happened on the resin parts and the metal was not affected. Fortunately, I had stuck around and was able to get most of it off with a simple wipe down.

Anyone else have anything like this happen?

Vince

I don't use resin, but thanks for the head's up.

I have seen that when the resin or the outside is cold.

Where did you spray and whats the temp like where you live?

May also be a bad batch of resin – some varieties may "seep" oils over time, especially if the mix was off. There's not much you can do about it, although sometimes leaving them out in the sun for a few days may leach the worst of it out over time. Just make sure the spot you you leave them in isn't getting too hot – you don't want to melt them, after all.

So the Primer was fine until you used the Krylon spray paint?

I had a similar experience. I had primed with Krylon primer. Painted models with Vallejo acrylics. All was good to this point. I then over sprayed models with Krylon Matte finish and all the paint and primer lifted up and wrinkled as if I had hit it with a heat gun. Most of it laid back down when it dried, but this was really upsetting. I thought it was the Matte finish.

The same thing happened to me with some DP( resin models; primed with car primer, painted with several layers of paint, gloss varnish then matte varnish. The last caused the whole thing to bubble up, so I had to strip them down and start again. After scrubbing the models with the paint stripper (Fair Power Sparay) and a good rinse under running water, they've since been painted a second time with no issues. I think it was insufficient cleaning the first time round.

Did you use a good de-greaser to clean the resin parts? DAWN generally works, however, some newer resins require a good wash with something similar to Castrol Super Clean in the autoparts store – to remove all of the oils and get the parts super clean for repainting. It is akin to stripping the resin model before you start painting it.

I've had it happen recently with some of the Heavy Gear terrain pieces which are resin. I had to scrub them off and then re-prime. Worked fine the second time around. Fortunately, I noticed that the primer was lifting up after handling them to see where I wanted to start painting first. It was a slow process – I let them sit primed for over a month and then the primer just flaked off. Scrubbed them down, and re-primed. Worked fine. I should have done the Castrol treatment before I primed in the first place, but thought that the DAWN scrub was sufficient.

I believe these were recently cast thus the oil level may well have been much higher than normal. The priming was done in-doors and at around 68 to 72 degrees. I had a clue after priming when it seems that the primer would rub off during handling.

Vince