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.
