Arc Welding Repairs
Background
I enjoy welding. Soon, I hope to acquire at least a DC tig welder and some argon gas so that I can begin to learn the art of tig welding. I have only had my 36-volt 100-amp arc welder to use in recent years, made from microwave oven transformers and scrap copper cables. I haven’t had what can be considered a lot of practice with stick welding, but I have been able to make some robust repairs and solid connections between parts in some of my large-scale metalworking projects.
For example, in my electric bike project, I wished to join two sprockets to be parallel and concentric to each other, so I separated them with steel spacers of the necessary thicknesses and stick welded them all together. My first attempt to do this did fail spectacularly, but I drilled out and grinded away the welds and tried welding everything together again, getting a much more concentric and parallel final product the second time.
In my electromagnetic Mjolnir hammer project, to ensure a sturdy connection between the handle and the electromagnet core, I welded the two together. This was one of my first welding projects with my stick welder and it was more for practice than anything else, as there were multiple fastening methods available to choose from. My half-inch corded drill never operated properly from the day that I got it because a part of its chuck mechanism had failed internally, and it would not firmly grasp anything in its teeth. I was able to deal with this issue for almost seven years, relying on friction to drag the mechanism into a tighter grip, but it would fail under too much torque.
Using my Dremel, I cut open the chuck and removed the steel outer-grip. The plastic section below it had been poorly adhered to the outer metal grip with some adhesive, the only interface between the two, a connection that failed before I ever laid hands on the drill. I then found that there were metal cams inside of the chuck which were designed to ratchet and slowly tighten its grip somewhat like a differential screw. Since I could not repair the delicate interface between them and the outer cam surface, I instead exposed sections of the tightening ring and directly welded it to the outer shell. The drill doesn’t have the ability to “slow-tighten” after the welding job, which makes tightening the chuck by hand a dangerous and difficult task, but the grip is much tighter and more controllable now.
Finally, when I came to own my bench vise, it was in desperate need of repair. I’m still not sure how, but its outer jaw had been bent a few degrees out of parallel with its other jaw either from extreme stress or poor welding on the manufacturer’s part. I say that because upon inspection, the connection point between the outer jaw rail and the jaw itself looked to have been joined together at the wrong angle to begin with. I believe that this was the case because of all of the large pool of welded metal that held them together at that 95-100-degree angle and the lack of a bend in the rail that could have created that angle any other way.
I decided to split the rail and recombine its halves after bending the joint back to the correct angle. Of course, before doing any cutting, I tried smacking it back into position with my 45-pound railroad-rail anvil to try and break the original weld, but that didn’t make any change. I cut the rail’s vertical supports with my angle grinder, leaving the top section of the u-shaped rail intact with its much lower moment of inertia, then I bent the outer jaw back into its correct orientation and stick-welded the vertical supports back together. I have since tested the welds by clamping the vise as hard as I could and accidentally bending its handle, and they withstood all that I could throw at them.