Painting Resin

[Jeff965]

I recently purchased some excellent buildings from JR miniatures and tonight I started to paint them. The paint will not take at all, I've scrubbed the buildings in soapy water prior to painting but the paint (Coat de Arms) runs into little blobs all over the model.
Can anyone help it's like mixing water with oil

[OSHIROmodels]

Give them a light coat of car primer (Halfords is best if you're in the UK) 

cheers

James

[Jeff965]

Thanks James will give it a try.

[mikedemana]

Try popping them in the dishwasher for a cycle. I do that with all my Acheson Creations stuff and it works great. I then spray it flat black, and follow that up with a 50/50 watered down acrylic paint.

Mike Demana

[Jeff965]

Cheers Mike, I gave them a good scrub in the sink but when I came to paint them the paint just pooled on the surface and simply wouldn't take to parts of the model. I've never had this before but I've never brush primed before either so I'll go back to sprays I think.

[zizi666]

Try popping them in the dishwasher for a cycle. I do that with all my Acheson Creations stuff and it works great. I then spray it flat black, and follow that up with a 50/50 watered down acrylic paint.

Mike Demana

NOOOOO !
I've seen 15mm buildings deformed by a dishwasher.
If the temperature is too high, the resin can get soft and warp !

[Jeff965]

That's ok Zizzi, I am the dishwasher in our house 

[jthomlin]

I have recently been using a ' single-pack epoxy etch primer' spray can on resin pieces and it worked a treat. Just like on metal, dries very thin and you can't scratch it off with a fingernail after an hour of application. I don't do multiple coats however, I then use Vallejo primer from an airbrush as it works better with normal acrylics and I can vary the primer colours to get a zenithal lighting effect.

Cheers!
Joe Thomlinson

[grant]

I scrub my resins with a toothbrush, dish-soap ('washing up liquid' for you 'over there' types).

Then I airbrush them with Vallejo Airbrush Primers - colour dependent on what I'm doing. The primers work fantastic. No more stinky aerosols for me. 

[Connectamabob]

I'm not familiar with Coat de Arms paints, but from what little google dredged up, it looks like they are water based acrylics.

If so, then that's maybe part of the problem (provided you've ruled out residual mold release and surface oils "sweating" from improperly mixed/cured resin). Depending on casting methods, resin can sometimes turn out with a super-smooth finish that provides no "tooth" and encourages high surface tension in water based paints. It's not a deficiency in the material, but rather in the casting technique: the ways to avoid it are to seal your masters with a satin/semigloss primer before molding, and/or to powder the molds with talc between castings (this also helps hugely with air bubble prevention).

If this is what you're dealing with, then priming with something oil based (i.e. enamel or lacquer) before switching to acrylics for actual painting would be the solution on your end. Oil based paints are more "gummy" while wet, so unusually high surface tension alone won't prevent them from sticking like it can for water based paints.

You want to always prime resin as a rule anyway, since resin is generally more chemically inert than polystyrene or metal.

[Jeff965]

Thanks for all the advice guys much appreciated.