“What’s this?” says the CEO. “Styrofoam? Isn’t that…well…cheap?”
“We prefer to say it’s economical,” replies the PR Guy. “We also prefer to use the phrase ‘architectural foam’ in exchange for the banal Styrofoam.
“Banal,” says the Chief Engineer. “Don’t that mean bathroom?”
Well, there you go, sunk to bathroom humor within the first fifty words…it’s got to be a record!
As you may have heard, we abandoned nasty, splintery, naily old plywood in favor of light, smooth, easy to use Styrofoam. Yes, Styrofoam, the king of take-out food materials, has proven itself to be right at home on the garden railway.
Like most wonder materials, however, Styrofoam has some interesting quirks that take a little getting used to. For one thing, it’s messy. For another, it ain’t natural, folks, so be prepared to leave the green road. But once you get the hang of it you are in for an interesting treat.
I think I bought the wrong Styrofoam for my project. I’ve read where other modelers have used architectural foam to great success. Theirs, however, is that dense cell blue stuff. I went to Lowe’s and bought a couple of sheets of what looked like architectural foam to me…4×8 sheets of white foam. When I got it home, though, I realized it’s just plain old Styrofoam , the kind your Chinese food comes home in, sandwiched between two thin plastic sheets. I was gravely disappointed, until I started working with it. Trust me, you’ll like it.
Cutting this laminate Styrofoam is easy, and no special tools are required. If you’ve ever tried to cut plain old Styrofoam (like the kind that they packed around your new 8-Track player) with a knife, you know you’ll get Snowfall Over the Alleghenies; white pepper-corn dandruff that goes everywhere. Expecting the worst, I used the quasi-sharp knife blade in my trusty Leatherman tool. Because of that plastic sheet laminate, this stuff cuts smoothly and retains a reasonably clean edge…you can cut freehand curves and everything!
But here’s the thing: you gotta cut this stuff like a man. Don’t treat it like styrene, you know, where you make a shallow cut and then go back over it. Doing that here breaks through the laminate and exposes the white dandruff. Go straight at this stuff. Drive your knife all the way through both sides and cut it with a gentle sawing motion. You’ll find that it cuts like a dream.
You can make it curve, like inside the arch of my railroad bridge, by cutting through the Styrofoam from one side all the way down to the laminate on the other side. I cut through the laminate on one side and about halfway through the foam itself. Making sure to leave the laminate on the other side intact, I broke the Styrofoam along my cut lines. The uncut laminate acts kind of like a hinge and allows you to build remarkably smooth curvy things.
The ancient tool, fire, can be used to anneal the edges of my Styrofoam pieces. A candle did a nice job of slightly melting the edges, closing gaps between the large cells of the foam and making ‘em stick together.
Now, sticking is an issue. My current favorite adhesive is Plumber’s Goop. It works great and holds super strong to the laminate sheet. But it is unbelievably aggressive towards the unprotected Styrofoam. As the foam is naturally anhydrous…
“How can Styrofoam be ‘naturally’ anything?” mutters the Chief Engineer.
“Shush,” says the CEO as he lights a cigar. “Let’s just go with it.”
…and is extremely reactive to toluene-based adhesives, your choices are kind of limited. I cheated, and you might want to as well. I used dopey old Elmer’s Glue, knowing that it’ll work like a stick-um, and then screwed the pieces of my bridge together with gnarly 3 inch long deck screws. The thing is sturdy!
Oil-based paints, too, will attack the Styrofoam itself, although I’m rather certain they’ll stick just fine to the laminated sides. Water-based paints won’t stick, and oil-based paints will attack. What to do? Well, again, I cheated. I used straight water-based acrylics, but I didn’t mix ‘em first. I used the colored sludge at the bottom of the bottles. And I didn’t brush it on: I stippled it on. The thickness that comes from stippling the super-heavy paint makes it work kind of like a glue. All I’m trying to do with my acrylics is get a coating over the bare Styrofoam so that I can use enamels on it…my thinking is that the acrylics will protect the Styrofoam while the enamels protect the acrylics. I’ll let you know what happens.
Here’s the beauty of the Styrofoam: it cuts easily, holds its shape, and forgives your sloppy workmanship. You don’t need a scary power tool to cut it, and mega-projects like this bridge go together in the blink of an eye!
