I need to cut some EVA foam sheets (2mm and 4mm thick) using an SVG file, and foam cutting isn’t permitted in the CO2 laser cutters due to toxic fumes. EVA is not rigid enough to cut using the foam cutter, and the desired pieces would be too small to survive removal from a taped surface if cut by the Shopbot.
Does anybody here have a diode laser at home who might be willing to make some cuts for me in an outdoor setting?
How complicated of a cut are you trying to make? I highly recommend this BevAll tool in a variant that suits your needs. Jacob, the owner and inventor of the tool is a great guy. I printed a few thousand of them for him to get his business started.
I hadn’t known him previously but rather saw a TikTok of his and thought it was cool but noticed his startup was understocked… so I helped him out. Now business is booming because it’s such a handy tool.
See it in action here: TikTok - Make Your Day
Also, according to the internets, cutting EVA foam is OK… not sure about internal policy. If it’s OK at MakeICT… try it in fewer passes.
Wait… I know the project you’re working on… your EVA is SUPER thin and shouldn’t be a problem to cut with low power on the laser… and yeah, way too delicate for milling. The member I knew with a diode laser moved recently… trying to think who else has one.
EVA isn’t toxic, but as with any foam there is a fire risk. Since it’s not on the approved materials list, and other thin, non-toxic foams are on the banned list, the area lead would need to give permission first @xrunner
From what I’m reading, it isn’t toxic but it sounds like it could be messy since it can become tacky when cut. Unless someone else speaks out against it, I’m alright with using the laser under the condition that it’s closely watched. If it appears to make the laser bed sticky then cutting should be stopped to avoid making a mess. Maybe start with having another material under it to protect the bed?
Obviously, if it starts to burn the cutting must stop immediately and the fire extinguisher would be used if necessary.
Can it be cut with a hot wire?
Greetings,
I may have briefly talked to you in the FabLab about this before.
I have a 16x16 20 watt diode that i could test it on. Now that the weather is abit nicer, i dont mind opening the garage door.
I have no idea on settings, so would need a scrap piece to try it.
This project requires a lot of small squares be cut out… hot wire wouldn’t work. If I recall correctly, it is for an awesome custom acrylic keyboard project, so it is a grid of squares to be removed leaving just the between key webbing.
It’s POSSIBLE the drag knife on the vinyl table would work provided low tack spray was used to hold the item down… but I do think lasering would be best for this delicate piece.
The EVA foam is intended to be used for sound-dampening. And yeah, Brad is right, it does require a fair amount of closed loop cut-outs. I’d really like to try making the cuts with a simple diode laser: if it works out like I hope, I’ll likely just buy my own for future cuts.
As visual aides, I’ve included pictures of the foam cut-outs (and the non-functional prototype board) below:
@xrunner Okay, maybe a dumb question: who is the truest authority for granting permission to do try something like that? Would that be you, or is there a detailed process for something like that?
You’re good to go but please watch it as I mentioned above. Please report back how it turns out so we can update the wiki if necessary.
Out of curiosity, I’ve looked for some kind of authoritative guide or industry standards for laser cutting with different materials - some kind of Machinery Handbook equivalent for lasers - and so far haven’t seen one.
Awesome, thank you! I will certainly do all of that. 
Can ya post your findings… ya know, for science?!
@bradcozine It’s been taking me a bit longer to find the time to run over to MakeICT, but yes sir, I certainly plan to. 
Awesome! That acrylic looks great stacked!
Hey all, sorry it’s taken me so long to report back. I ran over to MakeICT on Saturday and got my EVA sheets cut on the CO2 laser cutter (Mario). Fortunately, everything went off without a hitch! I made my initial cuts by taping the EVA foam sheets to MDF board, but ultimately placed the EVA directly on the bed after concluding that the cutting process wasn’t making a mess of things. With the MDF removed, I’m happy to report that cutting produced absolutely zero smoke.
For cutting the 4mm foam, I used 30/25 for my Spd/Pwr settings; for cutting the 1mm foam, I used 45/20–though I likely would have fared better with even faster speed and lower power. After reviewing the laser cutting policies for other maker spaces around the country, one thing I made sure to do was keep the LightBurn “Air” setting turned on when making my cuts: there’s been some speculation that disabling air assist has the potential to cause fires if the laser power is turned up too high. And though not a safety concern, one piece of advice I would give to anybody cutting EVA sheets in the future would be to lay the sheets flat for a day or two before trying to make the cuts: it’s really difficult to force rolled foam to lay flat, which unfortunately impacted every cut I made (see image below).
Overall, I consider this weekend’s testing to be a success! If we’re going to add EVA to the list of approved materials for the CO2 lasers, it might be worth letting the cosplayers know: as I understand it, they use EVA quite extensively.
