In preparation for installing a heated print bed and just to clean up from some previous mistakes, I cleaned up my print bed yesterday. I sanded it with several different wet/dry sand papers, washed it with soap, applied a metal polish and then cleaned with acetone. I only did this to the top since it is where the glass will lay and the bottom won’t be seen often anyway. Having it so smooth will allow better heat transfer from my aluminum sub-bed to the glass on top. The aluminum will be used to distribute the heat from the nichrome square wave pattern under it so that by the time it gets to the glass it won’t cause tension, cracking and shattering. I’ve had enough of that already, thanks. I was running a pared down clothes iron as a bed heat source before but that was dangerous, heavy, heated too unevenly, ugly, hard to control, had to be turned off manually and dangerous. Safety is worth mentioning twice. The plan now is to do from lowest layer up, a foam thermal barrier, nichrome square wave heat element secured with kapton tape, aluminum plate and thermistor, glass and then possibly some kapton to print on if I’m not getting good results from printing directly on the glass.