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I got the very last of this version of the MT resin Camaro.. I was so happy he had one he
could sell me even though it had been discontinued..

I sanded it, washed it, and gave it a coat of testors enamel silver for a base coat.. looked great.

Then I wanted to run this transparent lime gold / green over it.. Also Testors enamel..
(however it was recently purchased on clearance, sealed but a few years old)

I shook and shook and shook to make sure it was mixed well.. I'm kicking myself for not shooting
a test onto some spare styrene..


This is what I got.. so disappointing.

How do I remove it without warping or damaging the resin?

Or do I just let it completely dry / harden for a week and try to sand it smooth?
(Pictures don't show how uneven it is.. every silver circle is a crater)

Thanks,



.

You should be able to strip it in 91% isopropyl alcohol, soaking, then pushing it off with a thumbnail then sanding. When you are satisfied that you have as much off as you can get, use Westley's Bleche White, a whitewall tire cleaner, to get the resin completely free of impurities that effect paint. Then you must use a high quality primer to seal off the resin from the exterior paint. The only times I have seen that happen to paint, it was something in the resin, who knows what, and the way to solve it that I found is the above. Good luck.

I guess depends on the resin. I just stripped the Porsche RSR a week or so ago, no problems.

Jon, that's "a little touch up" from Deal of the Century, right?

Alcohol CAN turn resin cheesy. Sometimes it will re-solidify as it degases, other times not. You might try brake fluid, but I would suggest testing it in an un-noticeable spot first.

Maybe it has something to do with how long its in the alcohol. I had it in only about 4 hours, until the paint softened, then I pushed the paint off with my thumbnail easily. I hear people talk about leaving a body in for days, but I never found it necessary.

I don't think I would chance it now I have heard from folks who would know, but as I say, I must have been lucky.

Here's that RSR
viewtopic.php?f=35&t=5819&start=750

Thanks, Jeremy! I was about to post and saw that you beat me to it.

The car in the picture sat in the alcohol for several hours - definitely not days. It was red when it went in the alcohol and it was red, but warped when it came out of the alcohol.

After the body aired out, it returned to a reasonable facsimile of its original self. It still wears the original red paint today. At least the alcohol bath seemed to help what was a less than ideal paint job.

Patrick

That's nuts. I remember when that happened, but I never saw that the red paint stayed on the car! I thought it was red resin or something.

What is resin, anyway? Is it some form of styrene or urethane?

Kev, I would let it dry for at least a week and wet sand the whole thing down with 400 to the silver base then maybe light sanding with 800. Then wash it good with dish wash soap (Dawn/whatever). Put some in your hands give at a thorough wipe down and rinse. Then let air dry. Do not use towel or rag to wipe dry. Can get contamination on the body. Then recoat or prime.

http://pc.dupont.com/dpc/en/US/html/vis ... heyes.html

Resin is a polyurethane, but there are so many variations that come under that label.

My FPF Spridget went soft and cheesy (about the consistency of mozzarella) after about an hour in an alcohol bath. Due to its thickness it did retain its structural integrity, and firmed up again in a day or two.

I have soaked a resin body in alcohol before but not over night. But I had primed it inside and out with. I have found alcohol has little to no effect on a good quality primer. I always use lacquer paint and it don't take long to remove it either. Not big on painting with out priming first either.

That is fisheye caused by a contamination - looks like dirty air, or contaminated substrate, or could be in either layer of paint.

- after paint is stripped (try wet sand with 400 grit instead of chemicals, should take <30 minutes), use a primer to seal off any remaining contamination (if you sand thru, put more primer on - finish sand 600 wet no sand thrus, then ready to paint). Paint in light even coats when trying to candy effect something. (especially on small stuff like slots it is easy to load up the candy paint because it is see thru)

Spray a test panel - the same paint might be ok, paint can last a long time - most always exceeds shelf life on label. (even paint hardeners if unopened)

Fisheyes are the hardest thing to troubleshoot in a paint shop...15 years as manu rep for the auto paint company means I got the call everytime paint problems happened, the painters somehow could convince the bodyshop owner it was the paint...only once did testing show any issue I investigated to be the paint (and a national recall happened thereafter). Too bad slots substrates don't like 2 part acrylic urethanes (but will work on most hard plastic and some resin bodies)...too bad auto paint is thick/heavy...auto primer/paint/clear dry is usually 6-8 mils. 6 coats testors dry is about 2-3 mils.

Hogan knows of what he speaks since that was one of my bodies ;

I agree on the contamination theory. I always recommend washing in Wesley's Bleech White before priming and painting. Some resins or releases just don't play well with paint.

I forgot about release agents from molds...try washing with ajax cleanser before any sanding - comet used to have real grit, now micro plastic beads. fisheyes are caused by organic or inorganic oils. soap for organic, alcohol for inorganic. I do both...plus wet sanding with soapy water should remove any mold release agents before priming.

After thinking more, looks like the silver base let the mold release float to the surface without causing craters, then when the candy hit it it went crazy. If your spray test card works, likely it was the mold release agent (dry sanding can force the mold release into the scratches)

I definitely will try Dave's method. He's been painting professionally for decades, after all. I don't agree that chemicals are a bad idea. Besides, in 1/32nd car bodies there are lots of places where sanding is either impossible or impossible to do without damage from sanding too far in a crevice, etc.