Thermo-molding PE & EVA
Thermo-molding PE & EVA
(OP)
I am thermo-molding crosslinked PE & EVA sheet into a floor mat and have hit the wall on some process details. I could use some HELP identifying temperature parameters for sheet preparation, as well as molding tips from some one who knows the process.






RE: Thermo-molding PE & EVA
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RE: Thermo-molding PE & EVA
The advice I can give is to very closely monitor the "orientation" that the extruder puts into the sheet. ASTM d1204 is one of the tests for it.
Also it is a crystalline material with a distinct melting point. If you get near it the sheet will start to fall quickly. So be very careful not to overheat it.
What is your problem? Where are you located?
Is this an OEM or aftermarket part? Why this material?
RE: Thermo-molding PE & EVA
I've been vacuum-forming Foamies from the craft store, but it only comes in limited thicknesses (2mm, 3mm, and 6mm) and sizes. (I can only find the 6mm in 9x12 sheets, which are way too small. I can find the 12 mm stuff as 2x2 floor mat tiles, but that's a bit too thick for my purposes.) Do they make 4mm? I'm guessing so, since EVA is used for so many things, but I haven't figured out where to find it.
EVA foam can be useful if you want a little loss of detail, e.g., to smooth out a shape as an intermediate step in making a buck. (I hate sanding.) Of course, the detail is much better on the inside, and I'm thinking of using it for making flexible molds cheaply.
I will second the idea that you want to be careful about scorching the stuff, and that it varies by make and model. Just among seemingly identical craft foams, Foamies brand cooks up (and scorches) faster than the off-brand stuff from Hobby Lobby, which I like better.
RE: Thermo-molding PE & EVA
link: http://hobbymolding.com/modules.php?name=Forums
RE: Thermo-molding PE & EVA
Thanks for the link, but I've been there (and various sites about robotics, RC model building, prop and costume making, etc.), and there isn't much depth of engineering knowledge out there in the hobbyist world. (With a few exceptions, like Doug Walsh.)
But perhaps your point is really not that I'd be better off there, but that this forum would be better off... if you think so, you're likely right.
I do think I'm technically qualified to be here (Ph.D. in CS, a career designing and inventing things, etc.) but I'm a clearly far from my professional expertise when it comes to plastics.
Paul