I don’t think there’s a job more tedious than painting Styrofoam. It would be simple to spray paint it all black for the base coat, but it’s Styrofoam, and it will bubble and melt into a soggy pile of acid when it reacts to spray paint. It reacts with just about any painting or gluing material. So the only real solution is to glue it together with Elmer’s Glue and paint it with Acrylic or water based paints. But since Styrofoam has all the holes and cracks between the white balls, you have to go over it again and again with a detail brush painting the inside of the holes with black (acrylic) paint.
I have experimented with multiple things to get the holes to close up, but nothing has worked. I’ve tried heating the Styrofoam over a flame, using the hot-wire foam cutter, etc., all to no avail.
On the subject of painting Styrofoam, I thought I’d discuss paints. I have this old Games Workshop Citadel paint pot (with the screw on lid) which costs anywhere from $2.50-$3.50. The new paint pots cost $3.00 at my local Tabletop gaming store. This is the paint that says “Citadel Colors” on the back. This paint pot has 12ml of paint in it and ends up being $.25/ml.
The next paint pot to discuss I bought at a local hobby shop for two dollars. This is also black and is acrylic paint. This paint pot costs $2.00 and contains 10ml of paint. So it’s less money for a little less paint, but overall a better deal: $.20/ml. I started painting one of my Styrofoam buildings with this pot, and it’s over half gone. I couldn’t feel justified spending $2.00 to paint one corner of a building, so I went out and bought the next bottle.
This large bottle of paint has 236ml of black paint and was $1.99. No matter which way you look at it, it was a good deal. It has a simple pop top, and has worked wonders on my Styrofoam Mordheim building. (I’m almost done with the base coat, and then I’ll post it.)
So yes, obviously the huge bottle of Acrylic paint for under $2.00 is the best deal for painting small and large Mordheim buildings. This ends up costing $.008/ml, and is what I’m looking for when it comes to base coating Styrofoam buildings for Mordheim. I have yet to see how the quality shakes down for miniatures, and only time will tell.