MD,
How old is that 600B bender you have?
We had an old one where I worked many years ago and the bender seemed like it was very well made.
I bought one myself just a couple of years ago though, to do a job with a lot of 500 wiremold bends thinking I would be ahead of the game, only to find that the quality was beyond poor. The shoe was cast so poorly that it looked as if the Chinese had just discovered sand casting. What a mess. It would make kinks and dents and scratch the hell out of the surface with every bend. I think I spent a good hour and a half with a die grinder and a course wire wheel on my bench grinder cleaning up the burrs and smoothing out high spots.
I remember the box said on the label, “proudly made in the USA”, but the shoe says China on it. I guess the two-piece handle is the only part of it still made in the states.
Anyway, the bender works fine now, but for all the aggravation, I probably would have been better off just sticking to a 1/2” EMT bender with a rag in the shoe.