[delcon]

Hi Tom

I am trying to implement css on my lathe. To do this I have taken your examples and altered them to my needs. My intention is to let one thread handle all the S parameter changes. This is why I added an other if-statement for RPM mode. I attach the c-program I am using.
Before going live on my machine I am testing with a slowed down loop and printing out the rpms that would be sent to my machine. Doing this I noticed sudden changes in RPM that I did not understand.

While investigating I found out that the calculation of the radius is not working as expected.

To test this I
- set the x-axis to about 200mm (diameter)
- do the "G96 D2500 S159.6" of your css sample in MIDI
- start my attached css c-program
- do a "G01 X50.8 F100" in MIDI

The attached console output shows that at some point while traveling from 200mm to 50.8mm the radius suddently drops and comes back up again. The end value seams also to be wrong. I think it should read one inch and not 0.89 inch.
The console output was done with a linear move from 200mm to 50.8mm. The radius does not reflect a linear move.
In the attached picture you see the end position in KMotion and the console.

[TomKerekes]

Hi delcon,

Sorry I'm not able to duplicate the issue. Are you sure you are not executing the GCode with Cycle start rather than sending the MDI command? I think that would do as you describe.

Can you be more specific what you are doing and what happens? What does the DRO indicate with respect to the Console Screen Radius?

What Version are you using?

Regards

[delcon]

Hi Tom

Thanks for looking at this. I did some more research on this and can report following. I don't want to sound complaining - your program is great and I appreciate your work. I just report what I noticed. Here is how to reproduce:

prerequisites:
KMotion 433l in lathe mode, metric
G54 set all offsets to 0
T1 X offset -50.

- Fresh start of PC with Kmotion and Kflop
- Machine Axis are at 0 since it is a fresh start
- start Kmotion, G54 and T1 is shown as active offsets ->the green X-Axis-DRO reads 0.000, but it should read -50. I looks like the Tool offset is not applied
- without Toolchange, DRO at 000, start my attached CSS handling c-program. ->No ouput of the c-program because PC_COMM_CSS_MODE is not initalized, reads 0
- execute G97 ->Console shows RPM Mode, but RPM does not match Kmotion Spindle Speed reading, also configured c-programs for S-Commands have not been executed
- execute G96 D2500 S159.6
- execute G1 X 200. F100 ->Console output as expected
- do a manual Toolchange to Tool No1 to apply the offset
- execute G1 X50.8 -> Console output shows Radius calculation error for CSS

not related to css, but worth trying:
go to console and execute a "Reboot!" -> "Kmotion present but not responding" Dialog, then "Cant connect to Kmotion Board" - only solution is to cycle power

I hope this helps to reproduce the behavior.

From the technical Point: would it be a disadvantage to do

DoPCInt(PC_COMM_GET_DROS,TMP);
DROx=GetUserDataDouble(TMP);

to calculate CSS?

Best Regards

Leo

[TomKerekes]

Hi Leo,

Thanks for looking at this. I did some more research on this and can report following. I don't want to sound complaining - your program is great and I appreciate your work. I just report what I noticed.

Not like complaining at all. I greatly appreciate your clear examples.

You are correct the Tool X Offset was not being used for CSS.

Here are some patched files that should correct this when applied to V4.33l (changed sources are included if you need them)
Index of /Software/Patch/FixCSSToolOffsetV433l

start Kmotion, G54 and T1 is shown as active offsets ->the green X-Axis-DRO reads 0.000, but it should read -50. I looks like the Tool offset is not applied

Well I believe Tool offsets should not normally be applied until after Tool Length Compensation is turned on with G43Hxxxx. The patched KMotionCNC will now apply them on program startup if the Tool Setup Option "Tool Length/Offset Immediately" and "M6 on Tool Table Changes" are both selected.

execute G97 ->Console shows RPM Mode, but RPM does not match Kmotion Spindle Speed reading, also configured c-programs for S-Commands have not been executed

Since no S Speed has been commanded and no M3/M4 Spindle on command has been issued I think this is reasonable.

- do a manual Toolchange to Tool No1 to apply the offset
- execute G1 X50.8 -> Console output shows Radius calculation error for CSS

Currently after doing anything that may change offsets (fixture, G92, tool, etc..) the G96 command needs to be issued to tell KFLOP about the change. That seems reasonable to me as one would expect the CSS rate to change when changing tools. Also something like a fixture offset change would result in a spindle RPM change. I suppose KMotionCNC could handle all these cases if you think it is unacceptable to have to specify a G96 after such changes.

With the new patch, if a G96 is performed after the tool change, things should now work correctly.

not related to css, but worth trying:
go to console and execute a "Reboot!" -> "Kmotion present but not responding" Dialog, then "Cant connect to Kmotion Board" - only solution is to cycle power

Sorry we haven't yet been able to fiure out a way to re-boot the board reliably without a hardware reset.

From the technical Point: would it be a disadvantage to do

DoPCInt(PC_COMM_GET_DROS,TMP);
DROx=GetUserDataDouble(TMP);

to calculate CSS?

Yes the disadvantage would be non-deterministic response (if the PC was busy the CSS speed wouldn't change on time). It would also use a lot of USB bandwidth constantly polling the PC.

Regards