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Will GW Chaos Black primer protect plastic models from catalyzing 2 component urethane high gloss clear coat?

I primed about 8 jet bikes and 4 skimmer with some duplicolor I had laying around but it must be old as it went on gritty. I am going to take toothbrush and soapy water to them tonight to get the grit off but don't want to buy more primer.

I have a can of gold ole chaos black but am not sure if it will protect the models or is resistant to a chem reaction.

Any info would be great, thanks!

I contacted GW today but they were no help.

They could only tell me their products were safe to use.

Not having much experience with urethane want to achieve a balance of best look possible balances with realistic cost.

Any got any xp in this?

Test the idea on some spare sprue?

Spray is never completely foolproof as a coating, there will be thinner areas. Perhaps spray and touch in with brush primer?

I would test it but the urethane I need to use is a 2k meaning it has to be activated by pushing a pin in the bottom of the can.

After activation is is good for 48 hours so once activated I am pretty committed as the urethane is $20 bucks a can.

I have called both GW and Tamiya and they don't know and recommend the same thing.

I guess I can pick up some cheap poly.

Thanks.

GW wont know gak about it. as the people you call are just phone jockeys

Nothing i can find shows that the urethane will effect the acrylic.

I think its worth the 20 to test it on some scrap model.

Wait like 24 hours to see if it works. then speed spray the rest if its ok.

Your probably right. Thanks all.

GW's plastic is nothing special, it's just the usual bog standard polystyrene, most spray paints are acrylic or enamel iirc (you'd have to check the can) but if it's acrylic I don't see a problem.

I also have exp. with polyurethane (PU) although spraying the stuff and not as an expanding foam is a new idea for me. I can say that I’ve used polystyrene with polyurethane resins and not had a problem, also most 2 part resins cure within a few hours it should say on the can how long it takes.

Also the reaction for PU is exothermic and heat catalyses the reaction.

If this spray of your behaves in the same way as the PU casting resins water might ruin your day so make sure you use it with a low humidity and make sure whatever you are spraying is bone dry (this is what makes spray paint go bumpy or spray varnish go frosty).

tl;dr It's fine, just make sure it's dry and if you still are not sure, test it.