I picked up my motor and VFD yesterday to start the drive conversion for my 1940s Monarch Lathe. The original drive used a 3 phase motor driving a DC generator which powered the DC motor - quite a system. It is an absolute treat to see the craftsmanship and attention to detail that went into these machines. Consider today, the majority of manufacturers are perfectly happy with producing junk for our throw away society.
The WEG motor/ VFD combination provides constant torque down to 20 rpm and I plan on eliminating the 5:1 gearbox, if I am not happy with the performance, the gearbox can still be adapted to the motor as it is a "C" face. What is ironic is that the cost of modifying these old machines ends up costing more than the purchase price of the machine. This motor combination was approximately $1400.00. The original flat belt drive may also be replaced during this mod.
1940s Monarch Lathe
DC Motor and Controller
5:1 Gearbox
WEG 3 phase, 3 HP motor with VFD
Be well...