How to make ground foam for pennies


Some time ago I read an article, or heard someone, describe a way to make your own ground foam for doing scenery on model railroads. Since I have an incredible amount of mountains to cover with puffball trees, and the cost of store bought foam is getting to be very expensive, I decided to see if what I remembered about making it would yield the results I would be happy with.  Now for the first, and probably the biggest problem, my memory is terrible. I vaguely remembered what the steps were but, I figured with the cost of the materials that I bought I would not be out too much if this did not work so, some experimenting was in order. I did remember that they used ordinary chair padding and craft type paint. Good so far, those were both available at the big box retailer. I also remembered that it involved the use of a blender, preferably an old one. So far so good, I had one in the basement that was slated for the garage sale we had this past summer and never made it out there. Now for the tough part, the recipe. This is where the experimenting comes in.


The first step that I did was to cut the foam pad (16" x 16" x 1" ) into small, approximately,  1" cube size. This size is not that critical as this just allows the parts to fit into the blender easier. I was able to cut two pads into cubes while watching the tube. The picture shows two pads worth of cubes in a copier paper box lid.


I then loaded the blender with the cubes. I just loose filled the jar at this point and turned the blender on a low speed.

I let this chop the parts for a minute or so, pushing the blocks down with a short dowel. While the blender is running the foam tries to climb the sides of the jar so you will need to keep pushing it down to the cutters. Be sure you don't stick the dowel into the blades or you will be picking pieces of wood out of the foam. While I was prodding the foam down into the cutters I added a small amount of water. I found this greatly helped the process. I only added about 1/4 cup of water. I found that this seemed to be all that was needed. At this point I turned the speed all the way up on the blender and continued to prod the foam down into the cutters. When the foam seemed to be chopped up fairly fine I added the paint.

I put in a fair size stream that was probably 1/4 of the bottle and continued to mix the foam. once the paint and foam were all mixed I added some more cubes. I added them until the color of the foam looked about right. The picture shows the English Ivy green color.

Just continue mixing the foam down to the cutters for about a minute or two to ensure that the foam is all mixed and chopped up to the texture you want it. Once that is done I spread it out onto a sheet of cardboard or paper to let it dry.

The two piles in the picture would each fill the jar in the center of the picture. All of this foam came from a pad that was 16" x 16" x 1" and a two oz bottle of paint. Total cost for this amount came to $2.00.


After I have been doing this for a while I stumbled onto another trick to use. I made up a load of foam in a hurry one night and it was wetter than usual. I did not spread it out to dry like I normally would. When I came back to it a couple nights later it was dried into one solid mass. Not sure If I would have to scrap it I threw it back into the blender dry and chopped it up a second time. Doing it dry this time yield a much finer foam than what I was getting at first. I have been doing this now for the last couple of loads and it works well. The only thing I have found is that with my blender I need to put in small batches and run them quickly as there is no coolant effect from the water and the bottom of the blender housing does get hot.