Does “Materials - Vinyl/Nitrile blend” on an “Anti-Fatigue” floor mat mean EVA, or is there something more specific to look for when they are vague?
These are definitely EVA. I cut them all the time. 20% power 50ipm on my PRU cuts em like butter.
Also $6.99 is a pretty good price.
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Anti-Fatigue says nothing about the material other than it is comfortable to stand on.
Vinyl / Nitrile means it isn’t EVA, it’s PVN which has PVC in it so you shouldn’t laser cut it.
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Thanks. I was curious, so I tried to find a mat matching the Costco description, and that is what I found.
Somewhat true, but you have to be careful. EVA is Ethylene-vinyl acetate which is perfectly fine to cut. Vinyl doesnt in anyway denote the presence of chlorine, except in the colloquialism “Vinyl” when referring to records made of PVC. Its really the C that is dangerous here.
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Search for EVA foam mats to find them.
Indeed. I looked up PVN and the vinyl is PVC. Nitrile is a form of synthetic rubber so I assume they are quite different mats.
The ones that were in my local Costco are not available online at Costco.com at the moment. They looked just like what HF sells, but with a tight hatch/grid pattern. Next time I am there I will try to remember to snap a picture of the product for further research.
I had to go look, but the ones I picked up at HF a couple weeks ago say they are Neoprene rubber.
If in doubt, pick up a pack along with some copper wire and do a quick burn test.
If the flame’s not green, go for it in your GF.
If it’s green, you’ve got new floormats for your GF room.
You could always tear a corner of the packaging, sacrifice a tiny spot for the wire test and return if it burns green… 
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Ive only ever seen PVC Nitrile referred to in this way. Never as PVN, which is an explosive.
Im curious to see what youre looking at. Do you have a link?
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I got a much better deal on those from Costco than I did from HF… both purchased the same day. One concern of mine is whether the “Microban treatment” adds anything nasty to the EVA that we should worry about cutting.
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http://www.fostek.com/vinyl-and-nitrile-neoprene-blends/closed-cell.cfm
And this says the full name is Polyvinyl Chloride Nitrile Butadiene Rubber.
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ahhh yes… I have seen mats made of that. Theyre fairly different looking in person and a bit less stiff than the EVA mats.
Good to see they spelled out the chemical composition. It starts to get hairy when the word vinyl is thrown in the mix, and if Chlorine is actually in there and they forget it.
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Can you please clarify this ‘burn test’? Obviously green flame is bad, but I’m not quite grasping the relation of the copper and the mat piece.
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Search is your friend. ‘burn test’ turns up:
https://community.glowforge.com/t/fun-way-to-test-for-chlorine-in-materials/4185?source_topic_id=8530
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Sure…
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You heat a copper wire red hot and then brush it on the sample to melt a bit onto it. Then you return it to the flame and get a green flame if it has chlorine.
If you get any other colour it doesn’t have chlorine so it won’t eat your machine. It may well still give off poisonous gas like hydrogen cyanide. I don’t know if the GF filter handles that or not but if you are venting outside it should be OK.
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Many thanks. Now I have to buy copper wire and a torch, too. (Love this, really, except I am going to have to figure out another space to play ‘shop’ eventually.)
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