I have converted a small 8x12 lathe by adding steppers with G202's and new ball screws on the X and Y.The spindle has a  Nema 34 DC Brushed Servo from HomeShopCNC with a G320.
Bob Campbell breakout board and a Sound Logic Encoder board. E2 500 count encoders on all axis including the steppers. Differential converters on the encoder lines to keep noise down.
I need the spindle to act as a lathe spindle sometimes and as a rotary axis other times. Now with a parallel port the spindle is limited to 650 rpm at 43khz. I think the 4mhz that a SS produces would be what I need.  Need more speed. I was wondering are there any hang ups going with the SS on a lathe in this configuration?
I read the manual seems like it would be very easy to hook up. Plus I can use my existing boards.

I don't want to end up with another paper weight like the G100 and the license I bought for it.

Donny

I use the SS on my Lathe with a 12.5KW AC servo for the spindle motor. When I first fitted the servo over the Christmas/New Year period I had issues with the accel and a few other things, Greg wrote me a special trial plugin which I had to set the accel in every time I started Mach, it worked well but was a PITA, I now have one that has the accel built in and it works well for me, someone else has said he has a knock as the spindle gets to speed and another when he stops but I have not seen that.
 CSS does not work well at all, I get contstant knocking when in that mode,  Greg is aware of it and hopefully it should be sorted sometime soon but I have been using my lathe with the servo spindle since the new year and its a vast improvement over the old induction motor and electromagnetic gears.
Pic below of the motor.
Hood

That's good to know it works. I will be ordering one tomorrow.

Donny

With the SS will I still need a single index pulse on the spindle or will it be fast enough now for a 500 quad encoder with a 2 to 1 gear ratio. Encoder is on motor not spindle. Spindle max rpm due to voltage is 1350 rpm.

Donny

If your encoder has an index pulse then you can use that otherwise you will still need the slotted disc. At some point in time the SmoothStepper should support full encoder integration for the spindle but not yet
Hood

Has the SS overcome the length of pulse problem that the mach pp had that made using encoder a problem ?
And does your lathe thread well ?
Thanks Drew

Yes, SS can use the Index pulse from an enocder no problem. Threading is great for me, always was even with the parallel port however I think the SS may even be better. Reason I say this is a key sheared in the headstock gears of my lathe and first I knew was as a thread started the spindle slowed down from 1000 to about 300 by the end of the thread, I was going to E-Stop but I noticed the axis seemed to slow as well. I let it complete the 10 or so passes and when I inspected the thread it was perfect
Hood