2 inch extruded foam, what to use. By the way, I can’t believe I found this stuff just 3 miles from me here in the deep south. I did a search here for the right glue to stick it to the plywood and it looks like Liquid Nails For Projects is a good choice (among others), but my search for what to best cut it with to fit the benches didn’t bear fruit. I need a clean cut, as clean as I can get so I’m thinking a utility knife, the type with snap off blades, would do the trick.
Am I on the right track? Pun not intended.
This stuff is pretty steep around here, I paid about $69 for 3 4x8 sheets. Is that a fair price?
Jarrell
Try a serrated bread knife or hacksaw blade. Cutting foam is not going to cause any harm to the bread knife.
You should consider getting the Woodland Scenics hot wire foam cutter. I was wary of it because it’s a bit high-priced (over $30) but I quickly decided it was well worth it. You can use a knife, but the short utility-knife blade (like the ones where you can store the spare blades in the handle) is too short. Cutting or sawing this stuff makes a big mess, too.
Unfortunately, the hot-wire cutter can only reach in about 6 inches from the edge, so if you want to cut a board in half, it’s not going to do the job. Still, for most of your cutting, this is the way to go.
I’m using Liquid Nails for Projects, by the way. I think it works great.
Jarrell - Up here in Ohio we pay $23 a sheet for the 2" thick stuff, so you did not get ripped off.
Jarrell, I used a snap-blade utility knife exclusively, but my foam was 1". Your 2" stuff will be tough to cut that way, even with a swede-saw. The hot wire might be best, but avoid the fumes.
Later, when you are wanting to refine the shapes of the edges of the foam stacks, use a wire brush. You’ll make lots of foam particles, but you have a shop-vac…yes?
Are we having fun yet? [:D]
Cacole, I’ll give the serrated knife a try. My wife is at work[:D]
Jarrell
Mr. Beaslely, I’ve heard so much good things about the Woodland Scenics cutter that I already have it on my short list. Right now I’m cutting the 4x8 foot pieces in half, either cross ways or down the middle, so I guess I’m going to have to go with a knife of some sort.
But, I definitely will get the WS foam cutter.
Thanks for your help!
Jarrell
Pete, thanks for the info, I had thought that it was that expensive because not much was sold here, supply and demand thing… evidently it’s just kinda expensive no matter where you are.
Jarrell
Crandell, I have a couple of new snap off blade type knives that will extend out over 2 inches so that might be the way to go. We’ll see if it works on 2 inch foam.
Thanks,
Jarrell
The following tools are quite useful for cutting foam:
Utility knife: score & snap, just like drywall. I know it works with 1.5" foam, not sure about 2".
Serrated knife: use that electric knife you assault the turkey with every Thanksgiving.
Japanese pull saw - Available at the Big Box Home Improvement stores, these are narrow kerf saws that cut on the pull stroke. Much faster than a serrated knife, not as fast as an electric knife. The “dovetail” saws make a pretty clean cut to boot!
You can also use any of the following power tools: circular saw, bandsaw, jig saw, table saw. The table saw and circular saw will create a LOT of electrostatically charged blue snow!
Hot wire cutter: best for shaping and cutting small portions, not so hot for busting down a sheet.
Darn! I’ll bet my wifes electric knife would have been the trick!! Oh well, I still have a little to cut yet.
Thanks Biker!
Jarrell
If your wife won’t let you use the electric knife, keep an eye open for one at garage/yard sales, flea markets; or even cheap ones on sale at Walmart, etc. That way you can have a knife of your own, and the wife won’t be nagging you about it.
Jarrel,
For the cleanest cut, I would go with the larger version of the snap off utility knife.
Use a staightedge like a drywall “T” square and cut both sides. I sucessfully make cuts this way for special fitted insulation (gee the actual intended use for this stuff).
Bob K.
Craftsman used to make some foam board cutting attachments for use with a heat gun. I don’t know if they still make them, nor have I tried to use mine to cut foam, so I can’t say if this approach is worthwhile.
Using a heat gun to cut foam presents heat hazards as well as health hazards due to the fumes released when cutting foam board.
I’m puzzled by the fumes problem. How is it that they allow the use of materials which give off toxic fumes when they get hot in residential home construction? Doesn’t that greatly increase the danger of dying in house fires?
Huh?.. you mean this stuff was made for other things besides mr?[:O]
Well, I never!
Jarrell
P.s. Bob, the utility knife does make the cleanest cut. I had a little problem getting it through the 2 inch stuff but if someone where using 1 inch I think it’s the way to go as there is no mess at all. Well, even with other methods there isn’t that much mess, not like with the beaded stuff.
Dan, Mr. Beasley… I wonder about the fumes also. I’ve heard so much about it. I’d really like to use the hot wire method to form hills and dig ditches etc. Sounds like it would be a lot easier.
Jarrell
[P.s. Bob, the utility knife does make the cleanest cut. I had a little problem getting it through the 2 inch stuff but if someone where using 1 inch I think it’s the way to go as there is no mess at all. Well, even with other methods there isn’t that much mess, not like with the beaded stuff.
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Jarrel,
The trick for cutting thick foam is a good straightedge and a couple of passes with the knife. If the blade tries to bind it is dull or you are trying to cut too much at once. Lub the blade with silicone spray for the real tough cuts if necessary.
On another post, I believe I saw your benchwork plan. Did you ever consider adding to the 4x4 ends of the mainline dogbone? Even 4-5" could give you 24- 26" radius, not limiting you to 22" only. This way you are not limiting yourself to the length of rolling stock and still have room for scenery to the facia. If the foam is cut but not glued, this can still be done. Just let the foam span the seam and fill in the back. For gluing such large pieces of foam (laminating), spread the liquid nail with a notched trowel, this gives a more even glue surface that will bond better. The notches allow trapped air that helps w/ initial tack and quicker drying. This is why I prefer to use ceramic tile cement for glueing foam (cheap, water clean-up, strong, long working time and easy to use. Whatever glue you use, mke sure that you weigh down the foam for drying. Pieces of scrap ply or boards w/ all the heavy objects you can find- a good use for all those old MRs.
Bob K.
Heat changes the molecular structure of some molecules, and the oxidation involved in the heating process makes toxic funes that do certainly kill. If there is a firefighter reading, they will be able to explain in more detail. It is the same everywhere, in aircraft, submarines, and in your home. These materials are safe as used, but how much of any fire situation is safe when a house goes up? Even wood smoke from joists and framing is going to put you down in a hurry if you don’t practise escape routes and drills (crawl on floor where cleanest air is found).
Jarrel,
The trick for cutting thick foam is a good straightedge and a couple of passes with the knife. If the blade tries to bind it is dull or you are trying to cut too much at once. Lub the blade with silicone spray for the real tough cuts if necessary.
On another post, I believe I saw your benchwork plan. Did you ever consider adding to the 4x4 ends of the mainline dogbone? Even 4-5" could give you 24- 26" radius, not limiting you to 22" only. This way you are not limiting yourself to the length of rolling stock and still have room for scenery to the facia. If the foam is cut but not glued, this can still be done. Just let the foam span the seam and fill in the back. For gluing such large pieces of foam (laminating), spread the liquid nail with a notched trowel, this gives a more even glue surface that will bond better. The notches allow trapped air that helps w/ initial tack and quicker drying. This is why I prefer to use ceramic tile cement for glueing foam (cheap, water clean-up, strong, long working time and easy to use. Whatever glue you use, mke sure that you weigh down the foam for drying. Pieces of scrap ply or boards w/ all the heavy objects you can find- a good use for all those old MRs.
Bob K.
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Bob, I have thought about adding to the table to give me a little more room and I haven’t glued the foam down yet. Are you talking about adding to two sides or just one?
Thanks for the tip on the trowel, I have one of those around here somewhere!
Jarrell