[phomann]

On another topic. With Mach3 I’m currently controlling my Spindle via Modbus. With the setup I can do semi rigid tapping using a compression/ tension tap holder.
My understanding is that PathPilot doesn’t support Modbus so I’ll need to use PWM for spindle speed control.

With that, presumably I’ll need to add an encoder to the spindle to synchronize the z-axis to the spindle speed?

Cheers
Peter


Sent from my iPhone using Tapatalk Pro

[kstrauss]

PP doesn't insofar as I know support modbus. However, LinuxCNC does. Since you'll be running a modified version of PP it might be worth considering further changes. See LinuxCNC Documentation Wiki: VFD Modbus for a little about modbus and LinuxCNC.

Note that you can use a T/C tapping head with PP.

[rodw]

On another topic. With Mach3 I’m currently controlling my Spindle via Modbus. With the setup I can do semi rigid tapping using a compression/ tension tap holder.
My understanding is that PathPilot doesn’t support Modbus so I’ll need to use PWM for spindle speed control.

With that, presumably I’ll need to add an encoder to the spindle to synchronize the z-axis to the spindle speed?

Cheers
Peter


Sent from my iPhone using Tapatalk Pro

There are a couple of ways to get modbus working with a vfd. I have been using vfdmod which seems to work well
https://github.com/aekhv/vfdmod/blob/master/main.cpp

I use a BD600 VFD from Conan motor (in .AU) and there is a complete config for it available on the linuxcnc forum which I used.

yes an encoder would be helpful. Using a Mesa 7i76 with your 7i92 and removing the individual drives from the G540 is probably the best way to achieve this.

I bought an optical encoder from Masso but it has 10 volt output so I'm not sure if the 7i76 would work with it. I am using ethercat so don't yet have an encoder input But I got good results cutting threads by thread milling withot the encoder.