Chinese Machine Quality Ranking

I have had better luck with older western made machines, but it hasn't been smooth sailing. My friend just got an old Bridgeport. These things can be really troublesome. There is a well-known machinist named John Stevenson or something like that who posts often on this topic, but I don't think he's on the site. Anyway, I came over to help my friend out, and it seems that he had a grinding sound coming from his vari-speed drive. The lower motor sheave was out. It had eaten through the bushing. No problem, get another one. Problem: there is a supply chain problem. Fast forward several months, and a box arrives with the $250 part. Everybody is super excited, and it looks like the part doesn't slip on. After much head scratching, it appears that the key slot is too narrow for the part. Wrong part, right? no wrong! The metal has grown around the slot since the shaft was forged down by the wobbling sheave. Even if you recut the slot, the sheave bushing will be loose in places. TERRIBLE, TERRIBLE design decision! Vari-speed drives should not integrate the motor shaft!!! Anyway, I've seen my share of China sourced machines which have taken up valuable floor space for months for various reasons: mysterious failure that repairmen cannot find, no parts, warranty service declined, extremely poor quality with parts that never quite worked, etc. But, I've seen my share of sorry old American machines. Stacks and stacks of them.
John Stevenson died about five years ago. He frequented many machinist forums, unfortunately not this one
He had a great aversion to Bridgeports, wet noodle I think he called them
Favourite catchphrase was Clumsy Bastard.
John.
 
I believe that the issues with the Bridgeport variable-speed drive are attributable to Bridgeport using a vendor-designed (and probably -sourced) drive. The fact that the motor shaft was used as an integral part of the drive was unlikely to have been specified by Bridgeport. It is far more likely that the vendor chose that design to fit in the space desired by the customer, in this case, Bridgeport.

It is not uncommon for variable speed drives to incorporate the motor shaft as an integral part of the drive.
 
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