i am building an around the walls layout and was thinking of having the width be 30 inches. my question is can i use 2 inch extruded foam insulation for a benchwork base or would i have to have plywood underneath the foam.
thanks kevin
I have 2 inch foam sitting directly on shelf hangers screwed to the studs. It won’t take a lot of abuse but works fine. If you use a shelf hanger on each stud and go easy on the plaster it should work finer.
As Arthill said, it will work but you really need to be careful. One elbow in the wrong place and you’ve created a new pond site. [:)] I would run at least a 1/4 inch of plywood sheet under the foam and screw that to the shelf hangers for a little extra protection.
I have the same type of setup, but I have 3/4" plywood under it supported by 2x4s as a frame and support. I suppose it could be done, but would be concerned about weight on it as you start building your scenery…sometime or another you will have to get up over the top of it to work…the foam surely wouldn’t hold the weight. Good luck…
I have 1" foam supported with an L girder type stringer. These are consturcted with a 1x4 on the top, with a 1x2 making the “L”.
They are set on about 8" centers atop the supporting frame work (2x4 legs with 2x4 support arms or a Linn Westcott style wall bracket with 1x4 box girder support arms) with the foam glued directly to the surface of the 1x4 “L”.
So far I have to say it’s worked very well…But, I do now think that 2" foam would have even been better for two reasons:
First, I could have done more shaping down as opposed to building up contour.
Second, It would certainly be stronger. But, on the other hand, I’ve only had one mishap with broken foam where I tipped off my work stool, putting my elbow where it was never intended to be, and is also an area where I had no support under the foam (an overhanging edge) above the outside “blob” for my helix.
Foam is the way to go…In my book! Good luck with the project.
Not to stir up a can of worms… but I’ve done foam, and I’m now back to plywood. Got tired of difficulties mounting Tortoises, attaching wiring underneath, lack of ruggedness, and sounding board effects of foam. The idea that it’s easy to stick a tree or a scenic piece into foam doesn’t hold up. The foam won’t hold them (or anything poked or nailed) securely.
Nice for cutting a gulch I guess, but otherwise… give me good ol strong plywood.
The Foam is supposed to be used to fill the Hill and Valley scenery for portable benchwork that is covered with some type of shell material.
My method is to use frames of 1"x3" wood strips to frame the foam on the sides and 1"x2" wood strips to support the foam underneath every 12" to 18".
Andrew
My layout is all 2-inch foam, supported on a wood frame of 1x4’s and 1x3’s. I make riser trestles out of 1x2’s to adjust the elevation. I’ve got no supporting plywood at all. It’s a free-standing table layout, and I’ve never had to lean on it, either deliberately or accidentally. My table is on wheels and I do push it around the room now and then, so the light weight is a big plus.
This has worked fine for me. I do not use Tortoises, though, and I can see where this might be an issue. One thing I like is the ease of wiring - poke an ice pick through and you’ve got a hole. For thin wires that don’t want to go down the hole, use a straw as “conduit.”
I also stack foam to make higher elevations, and cut it out for ditches, etc. It can be easily trimmed with a knife, or cut with hot-wire or a hot-knife. Score-and-snap works pretty well, too, if you score it deeply enough.
You’ll need SOMETHING under the foam; 30" is pretty wide, and the foam WILL sag a bit.
The good news is that you won’t need much. My new layout will have a few areas that are 30" wide too, and I’ll be using metal shelf brackets, 1x3’s cut 30" long, 1/8" or 1/4" Lauan plywood, and 2" foam. That’ll be more than strong enough to support the wider sections of the layout.