Welding over a long period of time generates high amounts of heat (remember steel melts at around 1400 °C). In an earlier post about manual 3D printing it was mentioned that regular breaks must be taken in the welding process to avoid overheating of the both the welding apparatus and the print product. In order to prevent the plastic 3D printed parts on our machine from melting it was decided to re-manufacture critical components out of aluminium.
A heat shielded box will be used to protect the rest of the machine from the heat of the product and to contain most of the molten metal bits which fly around. The box is made by bending a 2 mm sheet of aluminium, it is then lined with slabs of light weight, heat resistant tiles. These tiles were thoroughly tested beforehand by welding right on top of them with varying power settings of the machine (note: for 3d printing only the lowest setting will be used). At low power settings the tiles could be picked up by hand immediately after welding. Damage occurred only when large pools of molten steel came in direct contact with the tiles when welding at with the highest power setting. To protect the MIG torch from sparks and molten metal a simple shield was fabricated from sheet aluminium, this was attached to the torch clamp.
Heat resistant tile after testing, it discolours at high heat but is damaged only when in direct contact with molten steel.
– The Metalprinters