Foam core – as a construction material for dollhouse structures – has its advantages. It is light weight, easy to cut, inexpensive and available almost everywhere (Hobby Lobby, Office Depot, art stores), but some of its benefits actually become weaknesses. Because it is lightweight and thin, it also warps when you try to wallpaper it. Also, the light weight factor makes it hard to attach anything very heavy (shelves, siding, sconces). I also find it hard to assemble walls together because any clamps that are long enough are pretty heavy.
But most of these things can be overcome. For this Tiny House project I chose very thin exterior covering so I could weight it down and keep it flat. My goal was something like this inspiration photo – combination of painted and stained siding (source: itinyhouses.com):
I loved the streaked wood grain from the inspiration Tiny House. I will tell you how I simulated the exterior stained panels.
But first, for the UPPER EXTERIOR COVERING- I used poster board that I previously painted a dark gray. The poster board was thick enough to disguise the seam from where I patched two pieces of foam core together (previous blog). After the paint dried, I laid my wall shapes on it and traced around them. I glued this on with white craft glue (Crafter’s Pick). Note that the poster board only covered the top half of the outside walls.
For the LOWER EXTERIOR - I had some very thin (1/32 inch) sheets of balsa wood lying around (yes, Balsa! Can you believe it?). Very thin, cracked and dinged up but I did get it to work. Photo below shows the label on the back of one of the sheets (after I had stained the front side so you can see the stain seeped through). The piece under it is the front of another stained sheet.
I was able to get the streaky look by applying several swaths of different colors of wood stain using a rag. I tried to dip the rag just in the top of the can so the color wouldn’t be too dark. The colors I use were:
Minwax Natural #209 (almost invisible)
PPG Penetrating Wood Oil in Oxford Brown (darkest stripe) and
Minwax Colonial Maple #223 (kind of reddish stripe)
I had three or four of these 24 inch long balsa sheets. I did a light / medium / dark strip and left a little unstained strip between each stain stripe. I tried to repeat the pattern across the entire length so I could later match up the panels on all four sides of the structure.
Pics are kind of bad because they were taken in the garage with poor light. I used wood glue to attach the balsa panels.
Trimming the windows - I used coffee stirrers to frame the windows. I painted around the foam core edges so the white wouldn’t show after the wood trim was glued on.
One more foam core construction note - Assembly and Gluing:
There are three types of clamps in the photo below. It was hard to find clamps long enough for this project. The black and yellow ones marked "Irwin" and the silver aluminum one with blue (bottom right of photo) were borrowed from my husband. These are probably from Home Depot. The small, thin brass one at the top of the wall nearest in the photo was purchased at a Miniatures show. I love these brass clamps and one I had was just long enough for the project. I think Micro Mark also sells them. I recommend them highly.
Gluing foam core walls is very tricky. Here are my tips:
- Use Crafter's Pick Ultimate Glue. It is very thick and grabs quickly
- Use pins or small nails to hold walls at the corners just until you can get the clamps in place (some people keep the nails in and just cover over them after glue is dry). Since I had already covered the outer walls with siding, I just used very thin sewing pins and removed them later. I added wood trim to cover the exposed foam edges anyway.
- Get your clamps set ALMOST at the correct length before you put on glue. This prevents the walls from falling apart while you are struggling to adjust the clamps
- Get a friend (spouse, child...) to hold the walls for you while you get the clamps in place. Since I had no one available I used large cans of soup to hold the walls vertical.
- I glued and clamped the four outer walls with the inner wall in place (though not yet glued). Sometimes inner walls (or even just a scrap of foam core) can be used to brace the outer walls while gluing so they don't bow up.
- Floor - since this is hard to clamp (and there isn't much weight to the structure) - I glued each wall to the floor as I glued them to each other. Then after all the clamps were set I used pins pushed up through the bottom to hold the floor to the walls.