I discovered the best way to cut Polystyrene...

Art Mulder

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3,383
Location
London, Ontario
Hey Folks,

I just had to take a moment to share what I've learned today.

I have learned the absolute best way to cut polystyrene (aka: white styrofoam) in your shop.
It works the best. Guaranteed.

Here is the best way to cut polystyrene in your shop: Don't.

:bang:

My wife is half of the banner c'tee at church, and they decided that this Christmas they wanted to hang a large star in the church as part of the Advent decorations. I helped her design one in sketchup, and today she came home with two 4x8 sheets of 1-1/2" polystyrene. we designed a simple(?) 6ft tall, 3ft wide 4 pointed star. We designed two of them, one notched at the top, one at the bottom, so that they could interlock together.

Screen Shot 2013-11-29 at 9.05.05 PM.png

Then we went down to my shop to cut it out with the bandsaw and jigsaw.

:thud:

What a mess. We had a shopvac hooked up to the small 14" bandsaw, but there was still white bits of polystyrene everywhere. We had it up and down our clothes. The jig saw was coated. There were bits sticking all over the place. I vacuumed us, I vacuumed the tools, I vacuumed the sides of the cut styrofoam, I vacuumed us again, and then did the whole round again trying to suck the little pieces that were stuck by static everywhere. Undoubtedly there are still little bits that I'm sure I'll find tomorrow.

Y'know, sawdust might be a bit messy and a known carcinogen, but at least it has the decency to obey the law of gravity! :gonnagetit:
 
Yeah, I've had much better luck with either a very sharp long blade from one of those snap off knives, or with an electric knife.
 
What Brent said but, . . . you've learned that the hard way. You'll find particles of that stuff stuck hither and yon via static electricity for a long time to come ;-)
 
I built a foam and fiberglass aircraft (I always get excited when a post says new plane).

Asked many other builders if they could only have one powered tool what would it be. Got many answers.

My answer soon turned out to be a very good shop vac!
 
If you only have a little to cut you can mount an abrasive blade (metal cutting) in your table saw or circular saw. It will melt its way through' If you have a lot to cut or complex shapes get a hot knife or better yet a hot wire cutter. There are several designs on a site dedicated to building your own tools that was posted to another forum a few days ago Here is the link:

http://www.homemadetools.net/
 
Hey Folks,

I just had to take a moment to share what I've learned today.

I have learned the absolute best way to cut polystyrene (aka: white styrofoam) in your shop.
It works the best. Guaranteed.

Here is the best way to cut polystyrene in your shop: Don't.

:bang:

My wife is half of the banner c'tee at church, and they decided that this Christmas they wanted to hang a large star in the church as part of the Advent decorations. I helped her design one in sketchup, and today she came home with two 4x8 sheets of 1-1/2" polystyrene. we designed a simple(?) 6ft tall, 3ft wide 4 pointed star. We designed two of them, one notched at the top, one at the bottom, so that they could interlock together.

View attachment 79602

Then we went down to my shop to cut it out with the bandsaw and jigsaw.

:thud:

What a mess. We had a shopvac hooked up to the small 14" bandsaw, but there was still white bits of polystyrene everywhere. We had it up and down our clothes. The jig saw was coated. There were bits sticking all over the place. I vacuumed us, I vacuumed the tools, I vacuumed the sides of the cut styrofoam, I vacuumed us again, and then did the whole round again trying to suck the little pieces that were stuck by static everywhere. Undoubtedly there are still little bits that I'm sure I'll find tomorrow.

Y'know, sawdust might be a bit messy and a known carcinogen, but at least it has the decency to obey the law of gravity! :gonnagetit:

Sounds like a Lucille Ball skit Art:rofl:

If I can't avoid working with the stuff, I just use a straight edge and a box cutter, with a new blade fully extended. Seems to keep the chaff to a minimum. Your results may vary.:wave:
 
BTDT, i was too embarrassed to post a warning otherwise i might have saved you from this disaster of a mess. I had a go at cutting a big slab of polystyrene to make some fancy corner protections for my travel trailer just before packing it away for the winter. The gutters on each corner ripped my cover last year and normally they are removable except not on mine. So i took a block of the thick stuff and cut it to all sorts of shapes and then hotglued it together to go over the protruding gutters. Along with duct tape to hold it in place while i put cover over. Solution worked but then came the clean up. I had to vacuum half the yard to get the white balls collected. To say nothing of what it does to a shop vac filter. Sorry i did not post a warning Art, i might have saved you. :(:eek:
 
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