Every day after work, and most of my days off have been out in the shop.
Converting both lathe and mill to 3 phase / VFD power using a Siemens motor for the lathe and Helmke motor for the mill, complete with new control panels for each.
Both motors got a new set of FAG bearings and new seals.
The lathe motor housing had to be machined and mounting brackets fabricated. A challenge, but not too difficult.
The mill motor was a pain in the butt. Adapting the 100l b5 flange to fit my PM935 involved several hours Tig welding the cast aluminum flange to build up enough metal that I could machine and drill/tap the appropriate screw pattern. Tig welding cast aluminum sucks by the way.
I'm never one to do things the simple, easy or cheap way. The control panels were fabricated from 1/8" aluminum plate, cnc milled, blasted, cerakoted and engraved. They needed fairly substantial wiring harnesses be built, to get all of the features that I wanted. Tachometers, power LEDs, Estops, potentiometers, relays and contactors.
Of course, the 100l frame designation on the original PM motor nameplate means jack squat. Nothing on it was even close to 100l spec. 100l uses a 28mm shaft, and the PM motor has a 22mm shaft. That meant boring the PM pulley to 28mm on the lathe, and broaching a new keyway using the motorless mill with a boring bar and a 1/4" hss cutter. That worked better than I expected.
Everything is coming together quite well though. The lathe is finished, and the mill is only lacking the VFD input terminal connections and final testing. I should have everything wrapped up by Monday.
The Siemens 3 phase motor made a stunning difference in the lathes overall performance. Significantly more than what I expected. The surface finish is better on everything, and on many materials several times better. Vibration and noise are about a third their previous amount.
I'm not sure how much of the improvement can be attributed to the 3 phase power vs the quality difference between the Chinese motor and the German motor, but the difference is drastic.
I'm hoping the German Helmke motor gives me a similar improvement on the mill, but I'm doubtful. The Taiwanese single phase PM motor was quite good.
