Step 4: Welding!
Once the welds are finished, they should be ground flat with the angle grinder. Be careful when welding or using the angle grinder on metal; things become very hot very quickly. Don't burn yourself like i did! Once everything is welded together, the holes for the "attachment units" must be drilled. These holes must match the 5/16" diameter of the pins and must be perfectly straight. That is why a drill press or mill is necessary for this step.