On Tuesday the 7th we went to metaallokaal, a metal workshop, to play around with some MIG welders and to get additional information on the welding process. Jeroen, the owner of metaallokaal, gave us some advice on which settings to use. During the instruction our group had a collective eureka moment when Jeroen demonstrated a “wrong” setting for the MIG welder. The feed rate and the power setting were both too low to weld on to the thick plate.
This resulted in a weld which did not penetrate the plate but instead lay on top of it like a caterpillar. This is ideal for the first layer of the print since we need small, controlled welds which are easy to remove. As an added bonus, we discovered that the power and feed rate could be kept constant for the subsequent layers of the print without introducing cracks or imperfections. For about an hour we played around with two seperate MIG welders, fine tuning the settings. Keeping the torch both perpendicular to the workpiece and stable (by hand) turned out to be quite challenging. In the future this will be controlled by the 3D printer giving a higher precision, and with some tuning, higher accuracy. Eventually we managed to create a “print” of several layers. A cylindrical structure and a “wall” were successfully printed. The last layers of the cylinder were printed continuously whereby the structure started to collapse due to the high amount of heat. When printing the wall structure the torch was swayed back and forth over a line, gradually increasing the height of the torch. Naturally, the corners of the wall became significantly warmer than the mid-section. This causes the corners of the wall to sag earlier than the mid-section. These are important factors which must be kept in mind when programming the motion of the torch in the 3D printer.
– The metalprinters