Polypropylene sheets in glowforge

[swedding]

Can I use polypropylene sheets in Glowforge

[evansd2]

Polypropylene as a family of plastics is laserable but it tends to melt rather than cut cleanly. You’ll want to test carefully and be extra vigilant for fires.

For more info about laser safety of materials check out #4 in my FAQ:

Common problems/questions

Hello! You’ve been referred to this post because you have a common problem or question. Check out the list below to see what this post can do for you. Just click on a topic that interests you. • 1: I’m new to Glowforge and really have no idea where to start • 1a: What other tools/materials should I buy to go with my Glowforge? • 1b: What are the overall best practices for my laser designs? • 2: All about masking/protecting your materials • 3: I want to design/make a box • 4: What materi…

[martin.anderson]

Yeah, if it’s thin (below 1.5mm roughly) and one of the normal kinds of PP you can do it, but it’s melty so take care. There are some variants that will more difficult due to other added chemicals (like fire retardants), but you’d probably know if you had one of those because they cost more.

One warning: once you’ve cut it DO NOT TOUCH the cut area until it can cool entirely. Melted PP is basically napalm – it will stick to you and keep burning while you frantically try to get it off, only making the burns worse.

I’m paranoid, but honestly I’d poke the cuts with a toothpick to make darn sure any globs were solid before getting anywhere near the melted PP.

[wesleyjames]

Is this like the guy who with one eye telling us to not looking directly into the beam?

[evansd2]

@martin.anderson

DO NOT TOUCH the cut area until it can cool entirely

This is a good point, and I’ve added it to the material safety FAQ #4. I mentioned the risks of melting as a mess but not as a burn hazard so this seems like a good thing to include.

4: What materials are dangerous to laser?

Return to the common questions index The main ways to damage your machine with a material are through fire, melting, or chemical reaction. Fire: Layered materials like cardboard and stacked papers can be fire hazards. Some foams are prone to fire. Acrylic is prone to fire. There are good reasons why Glowforge insists that you monitor the machine when it’s cutting, fire is at the top of the list. Search the forum any time you’re trying a new material, chances are someone’s tried it or will…

Thanks for the tip!