Centroid Community CNC Support Forum

Hi all.
I am having a hard time finding the correct parameters for the C axis on my lathe. I have labelled the third axis motor as "C" in the motor parameters and have set steps and rotation correctly.

I can't figure out parameter 93. If it is set to 1 (rotary axis), I have the C axis dro and the C jog buttons move motor etc however I don't have C axis options in intercon. If I set parameter 93 to 16(C axis selection), I have no DRO display, the C jog buttons do not function but I do have C axis options in intercon. I have tried both m50 and m51 commands in MDI but still can't seem to get any C axis control. I have also tried to set p93 to 17 with same results.

I am sure I am missing something, just dont know what

Do you run the newest software?

Best C-axis implementation is with 4.99

Uwe

Yes, I updated about a month ago to the latest software.

When P93=1 I can call C axis moves through MDI and intercon (manually entered G code, no C axis options available) and everything works as it should.

P93=16 or 17, I have C axis options available in intercon bit no control of axis at all

I have P93=145
Shows C-axis on the DRO only if it is turned on by M51

Since lathe Intercon can only index C and have no features for Y, I handcode or use fusion360 for parts with C-axis.

Uwe

So after the third frustrating day I don't think I am any closer. I have had the spindle axis (parameter 35) set to 3 and 5 to no avail. I can get function of "C" axis if I set P93=1 and did some testing. C axis DRO always present regardless of m50/m51 and manual g-code "Cxxx" controls axis as well as the jog buttons at all times. I have no C axis options in intercon unfortunately. If I set P93 to c axis (tried 16, 17, 145) I have intercon C axis options but no DRO or control of C motor at all regardless of m50/m51 commands.

On P93=16, I did find that if I made the C axis encoder the same as the spindle encoder (parameter 300 something, encoder inputs) with the belt off the motor the motor was slaved to the spindle and when I moved the spindle, the C motor would track it seemingly to correct position albeit in the wrong direction. This behaviour was regardless of m50/m51 entries. Very strange.

It is almost like the m50/m51 commands are not working however they do connect/disconnect the clutch (output#8) so it is being recognised. When I do have control of C axis, the m151 command states that there is no axis to unwind even if C axis is several rotations over 360°.

It also seemed to make no difference having the spindle axis set to #3 or #5. The C axis issues were the same.

I guess I will have to forgo the C axis options in intercon unfortunately and hand code all C movements which is disapointing.

Open to any ideas as I am out.

Your Report shows Version 4.82, not 4.99 with better C-Axis implementation.

How to run C-Axis with 4.82 is documented in one of my older threads, but I won’t waste time with this version anymore.

Uwe

v4.99 beta is available here.
https://centroidcncforum.com/viewtopic.php?f=67&t=8301

Awesome, I will update this tonight. I wonder what version I was on then when I updated. Hmmm

Okay guys,
I have updated the system and now have no control of C motor in either C axis mode (p93=16/17/145) or as a standard axis (p93=0/1). I have noticed that the axis active LED on the acorn is still red where the X and Z turn green. It does seem that the C axis mode is working as I now get the C DRO appearing and disappearing with m51/m50 commands, I cannot get any function from motor and the DRO shows constant zero. I have tried jogging and gcode to move it to no avail. I have noticed that the wizard doesn't set the C axis mode or define it as a rotary axis properly and I did change them over manually. I have completely cold started both acorn and computer several times incase this was an issue.

I did manage to get movement from the stepper by changing its encoder input to link with the spindle encoder. Once this is done the stepper tracks the spindle movement. This along with being able to jog the motor with the previous version leads me to believe it is a software setting issue and not a wiring issue.

I will try and swap the wiring over to axis 4 and set that up but Im not sure it will make a difference.

Any suggestions welcome please and thanks.

In your M51:

M101 /70014 ;Wait for Zero Speed

This works only if you have an Input VFDZeroSpeed set from your VFD

I use this:

N110
G4 P0.1
IF #50001
#101=#25009 ;Wait for Spindle Speed < 100 rpm
IF #101>100 THEN GOTO 110 ELSE GOTO 200
N200

to catch less then 100 rpm from encoder before turning C axis on.

Uwe