This summer I took the little radiant space heater down from the ceiling of the woodshop — it really wasn’t doing much to keep me warm out there. And we’ve had the scraps of a bunch of broken acrylic storage bins in the basement for 15 years, so I thought I’d finally see just what the process was like. Just holding the acrylic over the heater didn’t work so well — the reflector inside is designed to spread the IR out, so I ended up softening a pretty wide area. Good for some kind of complex curve you where you can clamp the acrylic in a jig, not so good for just making a corner.
So I bent up a piece of aluminum sheet to and cut a slit in it to channel the heat into a smaller area and shield everything else.. Bingo. I had to bend the acrylic a bit past 90 degrees and then hold it until it cooled, but the curve is about as tight and uniform as the factory-made ones the bin fragment had originally. Can’t wait to start playing with it to make real stuff.
As it stands, the space heater leaks a lot of heat out the sides. I might rivet on some kind of end cap, or I might just consider that a bonus for winter.