Hey, totally on board with this idea! I have a few thoughts: first, legos themselves are plastic, and it melts, so what if you were to take the constructed lego axis, fill holes at the bottom with wax, and use clay slip to make a waste mold of of the slip from the legos, and recast it in aluminum? that would give us a strong, solid frame of aluminum, with the ease of creation using legos? there is an electric kiln i saw on the net earlier today which can be made for under $120 save up coke cans, build the kiln and the lego pieces (except for the motors), then get clay and a defrocking agent measure out the volume of the piece, measure the weight of the coke cans, and extrapolate more volume than needed then take the piece to be casted in aluminum, make a channel to the top out of wax and a slanted ridge to funnel the aluminum inside, and fire the whole thing now you're using legos to make a metal 3d printer it might require a tad bit of machining here and there, but altogether? it's a cheap way to get a printer, then you can use the lego motors as cheap stepper motors from your pc, i'm going to lego land w/ my nephew next week, so i'll take picture each step of the way and post my results and how it goes, but do you have a complete list of parts?