[leomonti]

Hello,
I'm considering to use a servo motor/driver or hybrid stepper motor/driver as spindle in my a new lathe I'm retrofitting.
I think I understand that I have to use the spindle output by choosing PWM.
- What frequency to use for a driver that accepts step / dir signals? (HBS86H or Delta ASD)
- How to connect the spindle output "S" and and "0" to the step / dir inputs and the enable of the driver?
- Can I use an "axis" output to drive the spindle motor which must still respond to the g-codes M3, M4 and M5? (At the moment I am not interested in using the spindle as a "C" axis.)
- Servomotors or hybrids, usually, have a 1024 PPR quadrature encoder on board, but it seems to have understood that Planet MK3 controller prefers 100 PPR encoders for synchronization. Must replace the encoder on board?
Thank you for all helps.

[PlanetCNC]

I use ToAuto drivers in positional mode.
You don't want PWM, you want frequency (step) output from controller.
Use high speed optocoupler to connect controller output to servo driver step/dir terminal.
You don't need "axis" output. "output" outputs can do this.
Encoder that servo driver/motor uses is irrelevant. You need separate encoder on lathe shaft, 100ppr max, or use index signal.
ToAuto drivers have a option to generate encoder AB signals and ppr can be configured. This way I don't need to use physical encoder. Use high speed optocouplers for this "virtual" encoder signals.
.

[leomonti]

First of all, thank you for reply.

But I don't understand what output setting I've to set. From "output external board" or directly from controller(I've a MK3/4 and 2 of MK3/9)?
In setting menu of TNG, in the input/output setting, I find only "invert" radio button. How "output" outputs can do this?
I've not found a setting section where I can assign a function to output pin to have step/dir frequency signal on it. Must I create/modify any script?
Please, can you explain, step by step, how to realize this feature? Can you post some screeshot to locate the place to do this or a little schematic draw of your setting?
Thank you in advance

[joeavaerage]

Hi,
I use an second hand Allen Bradley 1.8kW servo as a spindle motor, and it's brilliant.

Servos are very power dense, that is they have the best power and torque for their size and weight. I would not bother with steppers, ALL steppers,closed loop or not lose
torque the faster they go. The manufactures of closed loop steppers would have you believe that they don't, pure BS.

I use 750W Delta B2 series servos on my new mill and so am familiar with them . The B2 series is the entry level Delta servo and it has a 160,000 count per rev encoder. You
will have to use the 'electronic gearing' features to reduce the required input pulse rate.

They are dual mode, that is to say that the primary mode might be Step/Direction with the secondary mode being Analog Velocity. Asserting just one digital input (of eight)
to the drive determines which mode is active. Note also that just about all modern servos have that dual capability.

With my servo I tend to use it mainly in velocity mode, that is, PWM generates a 0-10V signal and the servo speed follows. However if I assert that one input then it becomes Step/Direction
and I can use it as a C axis for rigid tapping.

The company in China I buy my servos from also sell ToAuto, their own brand, and very attractively priced they are to. I have no reason to doubt their quality or performance but the
documentation is poor and they have no set-up and tuning software. If you are new to servos then you want/need set-up and tuning software. There are many hundreds of parameters
required to program the drive, and trying to program them by pushing buttons like a microwave is very tedious and error prone. Pay the extra 25% or so to get proper Delta (Taiwanese made in China)
or DMM (Canadian made in China) servos, good quality, good documentation, good support and most importantly good set-up and tuning software.

Craig