PathPilot: VFD selection

I definitely understand that PathPilot is (mostly) just a user interface overlaid on top of LinuxCNC "under the hood." I'm trying to figure this stuff out to set things up so that I've got as few "variables" as possible when getting the system up and running, and to avoid any major incompatibilities.

I found some of the answers to my earlier questions. Part of the PathPilot interface is a "button" to select the high or low range/belting, and that's the only way the controller knows how the machine's belts are set up.

I also found a discussion thread online where users were talking about how to better calibrate the spindle speed of their Tormach mills because they were seeing enough difference between what the controller thought the spindle's RPM was versus what they were measuring that they expected to have problems tapping. Section 9.5.8 of the Tormach 1100 manual describes the process for calibrating the spindle based on issuing an M spindle speed command when the belt is in the low range, checking the spindle RPM and adjusting a setting.

tomdchi wrote: I also found a discussion thread online where users were talking about how to better calibrate the spindle speed of their Tormach mills because they were seeing enough difference between what the controller thought the spindle's RPM was versus what they were measuring that they expected to have problems tapping.

This must be based on a misunderstanding of how tapping works. Tapping (and threading) are slaved to spindle position as measured by the encoder, not related at all to the displayed or commanded speed.

To be honest, the absolute spindle rpm isn't that important as long as it is consistent.

tomdchi:
you appear to be trying to hard ! , are you using a tormach machine ? , are you using geared belts on your spindle
if not then you dont need to use it , remember this has been designed by tormach for Tormach machines , anything else
is simply Linuxcnc , for Tapping you need to have a resonable spindle Encoder . or opto's etc ,
Reading whats needed for a tormach machine or associated problems are only going to confuse you , even more .
if it works with linuxcnc then it works with PathPilot the same way .
the only difference is a few hal links to the GUI that you need to hook up for the display .

Yes, I guess I am trying hard! :lol: Thank you for your patience! I hope that my very basic questions and your answers are helpful to other people beginning to look into this.

I'm not using a Tormach but the PathPilot interface appears to be easy to work with "out of the box" rather than making all sorts of tweaks and additions to Axis. My situation is that I don't have an in-depth understanding of LinuxCNC or working familiarity with how to tweak it to make it work with a specific setup. (Or Tormach systems, which is why I'm asking basic questions about the interface!)

The discussion I found about spindle RPM was about using Tormach's "tension/compression" head - I'm not sure why these people were so concerned about specific RPMs in that case. I have to guess that this system has a very limited RPM range that will work consistently. I understand that PathPilot/Tormach mills can't do rigid tapping and that requires standard LinuxCNC and an encoder. Thank you for pointing out these details, but at least on these points I'm not confused (I think!)

I understand that LinuxCNC is very flexible and can be made to work with a huge range of CNC systems. But I have some experience configuring other open-source systems. Powerful... Very flexible... and not too difficult to configure and make work if you understand them deeply, but difficult if you don't have an extensive, detailed, deep understanding of the software. When you don't have a good understanding of a system, "just check the wiki" usually isn't clear enough!

I'm asking these questions so that I can minimize the range and extent of configuration issues. Also, I hope that when I do need to make "a few HAL link" adjustments, I better understand what I'm doing. Again: thank you!

just call me if you need a configuration for Pathpilot , to suit your machine , if your stuck
i would start by just looking at a configuration for linuxcnc first to suit your machine , and get to understand that first ,
this will give you a good starting point and a sound base of understanding , then look at pathpilot , with little changes the same
config will work with both linuxcnc & pathpilot .

Thanks very much! I have my controller "PC" set up and the LinuxCNC ISO booting off a USB stick, so once I've got the CNC conversion of the mill underway, I'll get standard LinuxCNC working and then work on PathPilot.