This Instructable will be yet another in my series of Shop Cheats. I had forgotten about this cheat until my current round of equipment repair. There were some bushings in need of replacement but proved difficult to remove from their bore. These particular bushings wanted to chip and break apart when struck with a punch. Which as you can imagine makes driving a bushing quite difficult.
Then I remembered how to cheat. A little something I seem to have picked up while learning to become a mechanic. A bushing is basically an inside diameter, and all I needed was to make it slightly smaller. Welding is an excellent way to shrink metal if properly preformed. Since the applied weld material is very hot it will shrink as it cools. So by welding a bead across the bushing, I ever so slightly change its outside diameter. Thus loosening it in the bore. This technique can be applied to both bushings and bearing races. And can be applied multiple times to the same bushing or bearing if needed.
A few notes. Be very careful about where you strike an arc. If you inadvertently weld off the bushing or bearing you run the risk of ruining the part. The hotter the weld the better. Size however is less important. The bushings I removed were quite thin, and would not hold up to a lot of heat. Because of this I could have burned through the bushing and into the surrounding part. Which was something I was very careful to watch.
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