Cutting extruded polystyrene foam

[Larry Folk]

Does anyone know if this product would be unsafe to cut fume wise or bad for the laser machine.
Also are there any difficulties in cutting it.


Model Plane Foam

This product is a premium extruded polystyrene foam specifically designed for the "foamie"aircraft model builder. It is 24"x48"x1/4" (6mm), 2 lb/cuft density, smooth, flat, unperforated, unskinned and white in color.

[Michael Hunter]

Fumes/machine - no worse than any other laserable plastic (e.g. acrylic).

Good air assist is a must to keep the cut edges from melting and slumping away.
Even so, the tops of the cut edges are likely to come out a bit rounded because of the stray heat around the laser beam.
Transfer or masking tape on the top would make the cut edges crisper - IF the tape sticks to the material AND can be got off again without causing damage!

Run the machine fast with the minimum power needed to get through the foam.

[Bill Jermyn]

I've also found it better to cut in multiple passes for a better edge.

[Kim Vellore]

You should cut at the lowest speed and adjust the PPI so it just cuts it. This is counter to what one would normally think but this works because it is the coolest cut. I cut styrene this way without it melting. This is the coolest cut because the energy per pulse the the same and running it at the lowest speed makes you have low PPI which gives the longest time to cool between pulses thus reducing the melt. It may not be good for any production but cuts the cleanest for plastics/foam that melt easily.
Kim