import lathe motor replacement/upgrade

JonathanK

JonathanK

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Im looking for info for upgrading machine to a better motor with less vibration. I am considering a dc motor and controller, 3 phase motor with converter or vfd, or any good info. I know many of you have done the same and any product info and pricing would be great. Also how you guys matched the pulleys and shaft
Thanks
JCK
 
I recommend a 3-phase motor, VFD combo. An industrial duty TEFC motor can often be found on eBay for cheap. Recommend automationdirect.com for a VFD. They have good prices and excellent tech support. A sensorless vector capable VFD will cost a little more, but will give more low speed torque.

On my Jet 13x36 belt-drive, the original motor pulley had a larger bore than the new 2 hp motor shaft. I made a sleeve and a stepped key to accomodate the pulley bore and the different keyway size. The only other mod was redrilling and tapping the motor mount plate to match the new motor's mounting bolt pattern. It all came together without a hitch and has operated perfectly for 17 years. I have never moved a belt on the lathe since. Speed range is from a crawl @ 5 Hz( power tapping, spring winding) to 1200 RPM @ 120 Hz. I couldn't have asked for more.

RWO
 
I just replaced the motor on my 1990's Grizzly mill. I got a 3 phase 1.5 hp motor from www.surpluscenter.com and a Huanyang vfd from the Y&F group on ebay. The motor was about $125 delivered and the vfd was $102 delivered. It was interesting that the vfd arrived the same day that the motor arrived. The motor came from Nebraska and the vfd came from Hong Kong. I think it was 10 days for the delivery. After receiving the parts, I noted that the pulley was too small for the motor. I tore the armature out of the motor, set it up between centers and turned it down to fit the pulley. I cut down a key and the motor was installed. I mounted the vfd on the back of the mill to keep it away from the chips. Home Depot provided a double pole switch for the 220 power and another couple of light switches for F/R and Enable. A metal box for the switches finished my purchases at Home Depot. Radio Shack was the source for a 10k pot. With the vfd in the back, I have the box with the pot and the switches mounted on the front of the mill within easy reach. It did take a few parameter changes to get the remote speed control and the F/R switch to operate. I also changed the maximum frequency parameter so that I wont burn up the motor / mill bearings. This vfd is also used to run spindle motors on cnc equipment and will run a spindle motor up to 26000 rpms. There is a lot of bad press about the vfd on the net but I have had no issues. The main complaint that I have seen is the keypad. I remoted the funchtions that I need to operated it and don't intend to use the keypad much.
 
Thanks for the Info! I ordered a North American Electric 3 phase 2HP TEFC motor, a Huanyang vfd, and a 4 step pulley to match the motor and existing pulley. Hopefully they will arrive next week. Im still trying to plan out my setup, I would like to locate a pot on the front of the machine and use the existing power handle(attached to the carriage) if possible. I will also have to figure out how Im gonna wire my oil pump..kinda seems like a waste to have a 240 circuit feeding a little dc pump.
 
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Piece of cake to use the existing power handle(attached to the carriage) for forward and reverse you just wire it into the 24V side of the VFD external control. The VFD does it have its own dial for adjust the freq. as I have an external pot. however I have never wired it into the circuit I do not adjust the freq. that much. Wire single phase 220 in and 3ph 220V out directly to the motor no switch in between. Follow the instructions that should come with your VFD. You think the replacement is best thing you ever did.
 
The part numbers depend upon the motor you are replacing. Go to the link previously provided and find a motor that will physically fit in your application. When you have determined what motor you want, then go to ebay for the vfd. They have several varieties depending upon horsepower and voltage. Mine was for a mill. The original question was about a lathe.
 
Do you happen to have any pics of your setup or info for programming the vfd for this application?
Thanks,
JCK
 
OK..I got the lathe up and running with the new motor and VFD! So far it seems to run great, but Im getting a high pitch squeal from the motor when VFD is running it. Also I need a tach to check the actual rmps on the motor as Im not sure what the bearings inside the lathe are rated for.

heres a pic of the pulley ordered...it had .006 runout, so I trued up the bearing surfaces and placed a set screw where the high spot was. this got it down to .0002.
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setting compound...the pulley is on a piece of stock I turned down to fit tight.

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VFD and disconnect wired up

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checking runout after setting the pulley in place

heres my first test run
http://www.youtube.com/watch?v=7jgSEb3TYDg
 
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