Help please: cutting styrofoam sheets

[bobbaitman]

[RobertMacy]

Make one. You're a shop!

I use an extra sharp matting knife, a straight edge, multiple cuts while gently 'spreading' the cut. You get a lot of tiny pieces, but not as bad as other methods I've tried.

[Tony Hwang]

Hi, For small job, I use soldering iron with flat blade like tip.

[gfretwell]

A table saw does a great job but if you don't have a dust collection system you will have a snow storm

[Nate Nagel]

I've always just used a super sharp knife or razor blade. For something as thick as 2" that might not work well though, as knives with disposable blades are not common that large. Maybe get an old kitchen knife from Salvation Army and just sharpen the snot out of it before use? (assuming you have a good knife sharpening system) You'll still make a little mess as you'll still get those little balls of styrofoam all over the place unless your sharpening skills are better than mine. Keep in mind that you will need to bevel the edges of the panels as well unless this is an old school one piece door. Might be easier to accept less insulation and use thinner panels.

good luck

nate

[Nightcrawler®]

I was going to suggest this for the long cuts, and a circular saw for the short ones. I used my rechargeable circular saw. Just pick a place to do all of your cutting and have a shop-vac handy.

[willshak]

Hand Saw?

[Mike]

Sorry folks. You got suckered by this dipshit. The post is over 3 years old.

bob baitman.

Not that that couldn't be his name, but what are the odds.

[DerbyDad03]

I hope you got it done before now. 3.5 years is a long time to work in a hot shop.

[RobertMacy]

ARRRGGGG!!!! On the GOOD side I have the same requirement right now, so have benefited from lurking.

[Chuck]

Try an electric carving knife. I did it that way and it worked out good. Put a sheet under the cutting area to catch the bits.

[bob haller]

dont forget insulation like this is VEY FLAMMABLE, and should be completely covered by dry wall or a minor spark could start a major fire....

[mike]

If you decide to build a hot-wire, be aware that the smoke from some materials is very toxic.

[nestork]

A minor spark could start a fire?

Bob, I'll concede that polystyrene is flammable, but if you've ever tried to burn the stuff you'll realized it's kinda hard to get it burning. It melts and pulls away from the source of heat.

If it was as flammable as you're suggesting, it wouldn't be used as insulation in virtually all of the flat roofs on the continent.

[gfretwell]

You really don't need to cut all the way through. If you score it 1/3 to 1/2 way it will snap off clean over a straight edge

[DerbyDad03]

...snip...

The 3.5 year old OP did say it was a shop. Things in shops sometimes make sparks.

I'm not saying drywall on a garage door isn't worth shaking your head over, but the warning itself has (some) merit. The suggested solution, well, not so much. ;-)

[mike]

Steel roll up door is a broad category. But at some point, the weight is gonna be a problem.

[micky]

I haven't tried this on styrofoam. I bought new a heater element, metal covered covered tube, 1/4 or so inches in diameter,, 10 inches long, runs on 110AC. I've used it to bend lucite or lexan, narrower than the heater is long. Mine is not that hot, although I've never touched it.

But if you got a toaster oven out of the trash, each element runs on

110-120VAC and many/most brands are not just the coiled wire, but they are some sort of glass or metal. tube. It might cut styrofoam well, or not, or maybe it will be too slow. Worth a little upfront, then you'd always be able to do so.

They sell the elements new too, I'm sure.

I think they get hotter than the one I have, or maybe it just seems that way because there are 4 of them on the top and 4 on the bottom (or 2 and 2)

[Nightcrawler®]

A regular toaster (for bread and such) has bare, metal bands that are straight for, I guess, 6 inches. Other than figuring out how to make it work without burning something up, this would appear to be an ideal place to start. Though, some older toaster ovens have the same set up and might provide longer lengths of the bands. Its just a matter of holding one in place without a shock/fire hazard, and after measuring the resistance of the entire device, replicate that resistance via high wattage dimmer switch and maybe a few power resistors or maybe even some form of DC feed instead of AC with a resistance adjusted for the DC voltage. More of an electronics question at that point.

[hrhofmann]

A sharp utility knife will cut about 1" deep, then turn it ove and cut the second inch from the other side. This is not rocket science, hardly even worth posting here!!!!!!!