PCB Heatbead for Home Etching

thingiverse

To begin with, I came across Prusa's exceptional heated bed design, but it didn't fit my available blank stock due to its larger dimensions and intricate narrow traces unsuitable for home etching. Thus, I created an alternative design featuring a 200x200mm dimension with hole centers 190mm apart. The resistance of this design is 0.95 ohms, requiring 1oz (36um) copper for etching. It offers 150w from a 12v source at 12.5A but was limited to 140°C to prevent glass cracking or FR4 PCB material damage. For double-sided boards, maintain the top layer as solid copper for heat distribution; otherwise, use aluminum foil or sheet. Avoid reproducing the top pattern if using professional services. Solder thermistor pads with a third pad for thermal contact and secure it with kapton tape, attaching wires to the thin pads near the edge. A hollow platform space might be needed for the thermistor placement. Alternatively, you can follow Prusa's setup by ignoring the thermistor attachment. Finally, solder heavy-gauge wires (15A rated) to large pads near the edge, using an automotive cable if available.