Polystyrene~ How to protect before painting

[richardmoore]

I am doing a commission at the mo of a "Wave" to go underneath a massive Marlin.

I have made it out of Polystyrene but now want to use a 2 pot mix resin/paint. However after testing it, it is showing signs of eating into it slightly.

I am just trying acyrilic paint as a buffer...in between...

While that is drying..I thought I would ask here if anyone has had any experience with this..and can recommend something I can put in between the coats or something to stop it melting.

With thanks
Richard Moore
http://www.artbyrichardmoore.com

[obseq]

Hi, Richard,

I've yet to come across any sort of chemical that *won't* eat through polystyrene. Even those products that claim to be suited for use on it just eats right through it.

Are you using blue, pink or white polystyrene?

Just offhand, i'm wondering if something like a plaster of paris wash would do the trick?

[fused]

Maybe gesso would work or a switch to urethane foam as a more permanent solution.

[GWayne]

Richardmoore,

Hi! Congrats on your commission. I used to design and build polystrene props for a theatre production company, and I have some advice about what adhesives to use and how to prep the polystyrene before painting it. Is the polystrene thermal formed or expanded? If the polystrene is expanded, then follow what is written below. Also try out the adhesive and primer on a scrap piece of styrofoam. ;)

I would stay away from solvent/alcohol based glues because they will melt the polystyrene. PVA/white glue, and Foam Tack Glue are the best ahesives to use on styrofoam. For painting use KILZ Interior/Exterior Water-Base Primer, and then topcoat with latex or oil-based paint, and clear coat if using a water based paint. Make sure that the strofoam is supported with a thick cardboard or wooden form to give it strength and stability. Hope the above info is of use to you. Good luck on your project!

GWayne

http://www.georgewayne.com

[richardmoore]

Thank you all for the replies to my question.

I ended up using a scrap piece of polystyrene, coated with wall board sealer (acrylic) twice. It only ate into tiny little pin pricks which wasn't a problem.

It dried over a period of a day or two and then I gave it a coat of two pot resin.

With no problems.

So thanks again for advice.

I will post a pic of how it ended up looking.

All the best
Richard
http://www.artbyrichardmoore.com
http://www.artbyrichardmoore.com/MARLIN_PHOTO_WITH_WAVE_BASE_op_580x600.jpg