This post will feature the BOM of our 3D printer. The base for our printer is a prusa i3 kit. This is a well documented design so we will not name all the parts that it contains. The build manual can be found on http://reprap.org/wiki/Prusa_i3_Build_Manual. The modifications to the original prusa design are quite simple. In place of the print bed we used a box constructed of sheetmetal. This box is isolated on the inside with a material that is normally used in ovens, the material contains vermiculite and is commonly available. The plate on which we weld lies in this box and is connected to the ground cable of the MIG welder by a piece of threaded rod, this rod goes through the box and the isolation material. Make sure to electrically isolate this bolt from the sheetmetal box. We did this by making a small “washer” out of wood.
We used an aluminium extruder carriage which we ordered at reprapworld. It is best to use a metal carriage since a lot of the heat from the welding will go upward and this might damage a plastic carriage over time. The torch holder is made from a small block of aluminium, we used a mill to fabricate this part but it can also be made with a pillar drill and a saw. Continue reading