Centroid Community CNC Support Forum

IF I am out of line or didn't post in the correct place, please let me know.

I am looking for info on how to program a tool changer. I have watched Keith's videos and read many posts and manuals and cannot seem to find detailed documentation on programming tool changer.

I have quite a few CNC machines all running Linuxcnc with Mesa cards. On the less complicated machines there is no issue, However on the big complicated machines there is an issue with the tool changer in that the old antiquated Interpreter code written by NIST is still there and the group over the years has patched and patched it to create functionality that the interpreter was not designed to handle. This causes issues and I want to change to something that actually works well.

I have a Biesse Rover 346 machine with several spindles and a drill back of 38 drills, that I would like to take a look at on how I can program a tool changer if it is possible with this system. If it is possibl, which I think it probably is I will retrofit my retrofitted machines to Centroid.

So Is there documentation somewhere that covers this? I read the operators manual and it states we can use macros and redefine M6, which is what I need so I would like to read up on this. from what I have read it looks like it will pass the Tx to the PLC and waits for the plc to change tool then receives a "tool changed" from the plc so it can continue on processing commands. The issue I see here is during the toolchange, the X,Y and Z axis needs to move during the toolchange, so is the PLC capable of moving the axis's?

thanks for your time,

Bob

Here is the tool change I programmed with Linuxcnc.

https://youtu.be/ndokzQzy0xA

I did find the Macro and skinning programming manual.

I did the toolchange in python in linuxCNC. https://github.com/bobbevins/Linuxcnc_p ... n/remap.py

Yes, that can be done with a Centroid control.

A few key points:
1) CNC processing, including stepping through CNC macros, is handled by one subsystem
2) PLC logic execution is handled by another subsystem
3) The CNC processor can send information to the PLC via M function requests, and via certain variable values
4) The PLC program can send information to the CNC processor via memory bits and variable values
5) Only the CNC processor can move servo axes
6) Only the PLC program has direct control of relay outputs
7) You often have a choice -- and this is largely a matter of style and preference -- whether to drive the sequencing
from the CNC macro (with the PLC performing discrete tasks on request), or to drive the sequencing from the PLC
(with the CNC periodically moving axes on request).

What you show looks a lot like a linear rack-type tool changer, found on countless router tables. Since the only distinction between one tool and another is the XY location where you find it, it generally makes the most sense to drive the sequence from CNC logic in the M6 macro, and just have the PLC open/close the cover, raise/lower tool bins, and unclamp/clamp the drawbar, on discrete requests from the CNC macro.

bevins wrote: ↑Wed Apr 24, 2019 8:24 am I did find the Macro and skinning programming manual.

I did the toolchange in python in linuxCNC. https://github.com/bobbevins/Linuxcnc_p ... n/remap.py

My recommendation to you is to approach Marc to see if he would be willing to be retained to write the custom PLC for you. it sounds like you have the knowledge to get the machine wired and working, just need the assist with the PLC.

Marc Leonard is CNCSNW, he is very busy, but very knowledgeable and as you have found willing to help here on the forums. For that, I appreciate his presence.

Marty

Thanks for the info.

I haven't decided which controller to select but the OAK board with centroid software will be a choice for sure.
I'm just trying ti figure out if everything will work as I expect, and my ATC will work the way I want.
I dont see the overall picture of the Centroid yet, but I am working on it.

Thanks for your inputs.

Bob