Settings for cutting polyethylene expanded foam

Hey guys,
Got a job to cut 1" thick polyethylene foam and I was curious if anybody has any settings as a starting grounds. Figured I’d cut one side and then flip it to cut the other side.

Flipping may sink you. At the very least it’ll add a lot of effort.

Check out #6:

If it were me I’d start with multiple passes if it’s more than about 1/4” thick. I’d start with 3 passes and 400-500 speed and then use that template to mack into the correct power level.

Edit: to expand a bit. Foam is tricky. At best it can get melty and at worst it can be pretty flammable. The rule of thumb is “cut quickly and not with too much power”, the idea being that you don’t want to heat the foam up too much as you pass. Excessive heat leads to melting and melting shrinks the foam away from the cut line.

Of course your tolerances are for you to decide but you’ll usually get best dimensional results with foam (and pretty much most materials To some degree) if you go quickly and with just barely enough power to get the job done.

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Thanks for the advice. I think I’m going to recommend going with EVA foam as I’ve had better experience with that. Expanded polyethylene this sounds like it’d be sticky in any sort of heat application. I added to the post the voice to text messed up it’s an inch thick so that’s why I needed to flip it

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Yeah your struggle will be alignment when you flip it. Foam is by nature flexible (and so resists exact placement against jigs), but Eva is probably better than some. I think even with careful jigging you’ll struggle to get the cuts to match.

I might try cutting it from one side, see if you can get through it? Curious to see how this works out.

It think some people cut Eva floor panels. Might be worth a forum search?

Yeah try this thread for some discussion.