Cutting Polystyrene

[Mr T]

I'm wanting to neatly cut some 50mm thick polystyrene. What type or knife/blade is best to use?

[DennisP]

I just used a sharp kitchen knife.

[Morcs]

but use very short strokes. trying to do long cuts like you would with cardboard will result in a really bad edge.

[ryanjury]

I used a saw like this http://www.talktalk.co.uk/shopping/imag ... -70x70.gif when I cut all the poly to make my fishroom it is quite easy to cut straight but a bit rough.. Otherwise use a very sharp knife, I believe the proper cutters are heated wires, but that gives off nasty fumes..

[smidey]

i used a craft knife with the blade extended right out & have it as horizontal as possible. mine have new blades so are sharp & long so i guess it would be difficult if they were shorter.

[Caryl]

I use a hot wire.

[Ira]

It's pretty easy to make a hot wire cutter. Just need a 12v battery and some nichrome wire. Have an old busted heater? The heating element in it is usualy nichrome. Then you just need a couple pieces of wood for handles and a bit of jury rigging it should be all ready to go.

[Zev]

And when you have got it going, don't leave it going on the kitchen table switched on, unless you want to get into trouble when you scorch the table...

[diver21]

i second smideys method.

[David R]

Thirded, a craft knife with a brand new blade works well. Make several shallow cuts with the blade on an acute angle to the poly.

[mickey_1975]

razor blades are great as they are really fine and dont rip through.

[wellmax]

It is also quite easy to cut to different shapes and sizes on a Band Saw. In a factory situation they use large band saws using a non serated blade which is a knife blade. Regards