He’s building a small CNC router of his own, using 80/20 extrusions (“the industrial erector set”), and needed some joining plates. This isn’t the kind of thing you just walk down to the hardware store and buy. I just happened to have some quarter inch 6061-T6 aluminum plate sitting around, so I made these for him.
Small pieces of high value material such as these can be quickly and easily mounted for machining using shellac, a technique employed by watchmakers and jewelers for centuries. It’s the original hot melt glue. I keep a few prepped boards around. Then all i need to do is heat up the aluminum on an electric heater, drop it on the board and turn on the vacuum pump. Then a thick “chill plate” is placed on top, and in a few minutes I’m ready to cut. When finished, the shellac is easily removed with nontoxic and noncorrosive borax solution.
I made 4 of the 8 hole plates shown and 2 smaller 6 hole plates, but I could easily have made a sheet of 20 or 30.