MDF printed beautifully

Laser cut MDF

Note: Actually, this stuff is not MDF at all, but Masonite.

In the high school class I've been teaching, we printed laser cut MDF and it did great. (Previous post here on where and how.)

MDF can be nasty stuff. It stands for Medium-Density Fiberboard and it out gases formaldehyde, especially when it's new. It's cheaper than plywood because they take sawdust and add crap to it to make the MDF. And, when there's a chance to breathe in MDF sawdust, use a respirator. The stuff I used for the class was old, and since I'm not working in a room full of MDF, I'm not worried about this known carcinogen. OK, now that you know what MDF is, the out gassing on new boards can be controlled by coating it with something. Luckily, you really should coat it with shellac before printing anyway.

I coated the MDF with 2 thin coats of shellac, full-strength, applied with a rag and lightly sanded after application, then laser cut it. I did not reapply shellac after lasering, so when we were done printing, I just wiped the board with a slightly damp rag to remove our ink--Akua Intaglio--so the wood wouldn't get wet and expand. (I can see the benefit of a 3rd coat of shellac post carving for this reason because MDF can get really out of whack with a little moisture.)

Even with the health warnings, I would use this material again without hesitation. I haven't hand carved a piece yet so I don't have experience with MDF that way, but for lasering/printing it worked great. MDF is denser than plywood so it will be harder to carve and tools will need to be sharpened more often, but it can be a plus with no grain or knots to consider.