Well finally had enough, had a vibration i just can't get rid off. have rebuilt my vari speed head about every 3-4 years now and its just had a couple of issues this year and thats it, tonight is its first night as no longer a vari-speed mill at least via reeves pulleys. The heat the vari speed use to generate made long runs in the summer miserable too. Im a very small shop to say the least.
Had some great luck and managed to score a truly lovely German 1.5Kw 90l iron framed 3 phase motor, final job of the reeves drive was to drill and tap the face of said motor to let me mount it to the plate i had laser cut last month.
Then Friday suddenly a gap in the work opens, despite having a lot of the bits too hand, i was not ready just yet, but today was a window as is Monday and Tuesday to get it done. I had the VFD drive, the speed control pot and the motor. Managed to also scrounge up some lovely L series timing pulleys and had ordered a belt to suit. Yeah one of the pulleys had the wrong size taper lock, £5.50 on ebay sorted that issue. Gear ratio is a fixed 0.75 and with a 1400RPm motor that gives me a nominal 1000RPM ish spindle speed, Vfd will happily drop that down and i had previously tested the motor upto 300hz, reality i will only run it upto 150hz for now on the mill, that will give me a top speed of circa 3Krpm, which is fine, i never really used the vari speed above 2.2krpm any how do to noise and im mostly milling steel or harder so loss of top ends no real concern.
Took a few goes to get belt alignment just right and it probably wants a nats more tension, squealed like hell being a new belt, but a quick squirt of silicone spray instantly solved that.
Temp hook up of VFD and she purrs, yeah motor fan is a issue at full wack, but she will have the shaft fan removed and a nice 6" powered fan made to fit should really reduce the noise. Vibration is gone at long last.
Hence its onto the control side, gutted the electrical cabinet, everything bar the isolation switch is out. New 12V supply to feed a good low voltage work light is in, VFD is in, New DIN rail is in for coolant relays. Temporary hook up to existing switches is wired, that will change though, but the switches are on a slow boat from china and hence will be a couple of weeks and i have holes to drill come Wednesday! Got a new Digital Tach that will replace the old speed dial on the head giving a real readout of spindle speed in high range, low range i will have to divide by 8 in my head.
Got the correct cable and glands to get tomorrow, then the final proper wire up of the power side and im back in business. Its just going to be nice not to have the uncertainty of things going wrong with parts i just can't easily and quickly get anymore.
Had some great luck and managed to score a truly lovely German 1.5Kw 90l iron framed 3 phase motor, final job of the reeves drive was to drill and tap the face of said motor to let me mount it to the plate i had laser cut last month.
Then Friday suddenly a gap in the work opens, despite having a lot of the bits too hand, i was not ready just yet, but today was a window as is Monday and Tuesday to get it done. I had the VFD drive, the speed control pot and the motor. Managed to also scrounge up some lovely L series timing pulleys and had ordered a belt to suit. Yeah one of the pulleys had the wrong size taper lock, £5.50 on ebay sorted that issue. Gear ratio is a fixed 0.75 and with a 1400RPm motor that gives me a nominal 1000RPM ish spindle speed, Vfd will happily drop that down and i had previously tested the motor upto 300hz, reality i will only run it upto 150hz for now on the mill, that will give me a top speed of circa 3Krpm, which is fine, i never really used the vari speed above 2.2krpm any how do to noise and im mostly milling steel or harder so loss of top ends no real concern.
Took a few goes to get belt alignment just right and it probably wants a nats more tension, squealed like hell being a new belt, but a quick squirt of silicone spray instantly solved that.
Temp hook up of VFD and she purrs, yeah motor fan is a issue at full wack, but she will have the shaft fan removed and a nice 6" powered fan made to fit should really reduce the noise. Vibration is gone at long last.
Hence its onto the control side, gutted the electrical cabinet, everything bar the isolation switch is out. New 12V supply to feed a good low voltage work light is in, VFD is in, New DIN rail is in for coolant relays. Temporary hook up to existing switches is wired, that will change though, but the switches are on a slow boat from china and hence will be a couple of weeks and i have holes to drill come Wednesday! Got a new Digital Tach that will replace the old speed dial on the head giving a real readout of spindle speed in high range, low range i will have to divide by 8 in my head.
Got the correct cable and glands to get tomorrow, then the final proper wire up of the power side and im back in business. Its just going to be nice not to have the uncertainty of things going wrong with parts i just can't easily and quickly get anymore.