[Jim Dawson]

Using an auxiliary stepper motor to do the indexing was something I considered before reading your post, but I thought that might be ANOTHER one of my bad ideas. Now that you basically confirmed that this would be a reasonable option...

I was thinking of using a 12VDC automotive air conditioner mag clutch for engaging/disengaging the stepper.
What do you think?

Ray

I am considering doing the same thing on my lathe using a DMM 1.8KW servo, and a 12V automotive air conditioner clutch. The air conditioner clutch will transmit about 10 HP so should work well for a NEMA 34 stepper.

My lathe is a bit larger than yours (10 HP spindle), hence the need for a larger indexing drive.

Well lots of machining centers are using a regular Ac motor driven with a VFD Drive and have no trouble with indexing, I have built them also with indexing using a regular VFD Drive, so it can be done but not with the spindle motor he wanted to use

I have not been successful trying to index my spindle motor with a sensorless vector VFD, maybe you could give me a hint as to how to accomplish it.

Motor: Fanuc 7.5 KW, 6000 RPM, 4 pole
VFD: Automation Direct GS3, 10 HP w/encoder input option
Encoder: 1024 line, RS422 output, driven from the spindle
Control: Galil DMC-1846

Speed control works perfectly, but have never been able to get it to index. The original Fanuc drive would index it to +/- 1 degree.

[allaces]

I am considering doing the same thing on my lathe using a DMM 1.8KW servo, and a 12V automotive air conditioner clutch. The air conditioner clutch will transmit about 10 HP so should work well for a NEMA 34 stepper.

My lathe is a bit larger than yours (10 HP spindle), hence the need for a larger indexing drive.

Jim,

I did not know that they were good to 10HP!
Clearly over kill for a Nema 34 stepper but I cannot think of anything else as simple and cheap.
Glad to see that this idea has traction...

I'm having trouble finding a small 1 to 2 HP 3 phase motor for around $100. there are plenty of 3600 RPM ones for that or less. I guess I might go for one of those and gear it up to 5000 RPM... which is the top speed I would like at the spindle end.

Thanks for the heads up on the clutch.

Ray

[Jim Dawson]

Sandy,

I did not know that they were good to 10HP!
Clearly over kill for a Nema 34 stepper but I cannot think of anything else as simple and cheap.
Glad to see that this idea has traction...

I'm having trouble finding a small 1 to 2 HP 3 phase motor for around $100. there are plenty of 3600 RPM ones for that or less. I guess I might go for one of those and gear it up to 5000 RPM... which is the top speed I would like at the spindle end.

Thanks for the heads up on the clutch.

Ray

Here is one in Langley. $175. Looks like these guys have a lot of motors, looks like a used industrial equipment seller. Might be worth chatting with them, their phone is listed at the bottom of the ad

https://vancouver.craigslist.org/rds...817156914.html

The small (<5hp) Baldor motors are rated at 6000 RPM absolute maximum.

[allaces]

Here is one in Langley. $175. Looks like these guys have a lot of motors, looks like a used industrial equipment seller. Might be worth chatting with them, their phone is listed at the bottom of the ad

https://vancouver.craigslist.org/rds...817156914.html

The small (<5hp) Baldor motors are rated at 6000 RPM absolute maximum.

Thanks Jim,

That looks like the place to buy for me. Close to home and no shipping!

Ray

[mactec54]

Here is one in Langley. $175. Looks like these guys have a lot of motors, looks like a used industrial equipment seller. Might be worth chatting with them, their phone is listed at the bottom of the ad

https://vancouver.craigslist.org/rds...817156914.html

The small (<5hp) Baldor motors are rated at 6000 RPM absolute maximum.

Not all of them only some models have the 6,000 RPM rating washdown motors mostly and they can go more I have run them over 8,000 RPM without any problems

[mactec54]

I am considering doing the same thing on my lathe using a DMM 1.8KW servo, and a 12V automotive air conditioner clutch. The air conditioner clutch will transmit about 10 HP so should work well for a NEMA 34 stepper.

My lathe is a bit larger than yours (10 HP spindle), hence the need for a larger indexing drive.




I have not been successful trying to index my spindle motor with a sensorless vector VFD, maybe you could give me a hint as to how to accomplish it.

Motor: Fanuc 7.5 KW, 6000 RPM, 4 pole
VFD: Automation Direct GS3, 10 HP w/encoder input option
Encoder: 1024 line, RS422 output, driven from the spindle
Control: Galil DMC-1846

Speed control works perfectly, but have never been able to get it to index. The original Fanuc drive would index it to +/- 1 degree.

For an example check you Haas with the Rigid Tapping and the spindle orientation, these are using a regular inverter duty Baldor motor the encoder is on the spindle, they use a lot of DC to control the stiffness of the motor to a point of locking the motor, which you can do with some regular VFD Drives does not have to be a vector drive I did it with this Bridgeport Boss5 standard Ac motor and Yaskawa VFD Drive Encoder on the spindle and a brake on the spindle

The control also plays a big part as well

[allaces]

For an example check you Haas with the Rigid Tapping and the spindle orientation, these are using a regular inverter duty Baldor motor the encoder is on the spindle, they use a lot of DC to control the stiffness of the motor to a point of locking the motor, which you can do with some regular VFD Drives does not have to be a vector drive I did it with this Bridgeport Boss5 standard Ac motor and Yaskawa VFD Drive Encoder on the spindle and a brake on the spindle

The control also plays a big part as well

Very nice and clean looking setup.
How is the disk brake sequentially operated?

Ray