Work offsets

[Riley]

I'm having trouble with changing work offsets in g code. Seems to work fine if I remove cutter comp. With cutter comp it does fine with the squares but when going to G56 and doing the circle it freaks out and comes up with some crazy toolpath. This was only coded for testing....any input would be great!

[BR549]

You cannot switch offsets WHILE in COMP.   Does it work ok IF you turn off comp then switch then reapply comp?

(;-) TP

[BR549]

OK I see you are working with Comp in SUBS.

First add the G54 to the startup safety line this sets the display position correctly in reference to the rest of the program.

After add it here the Program looks and runs ok. NOW be aware that Mach3 will draw the profiles as offsets BUT when it runs it doews NOT move to the profiles displayed position on the screen . IT WILL cut it correctly just not display the moves corretly.

(;-) TP

[Riley]

Hmmm.....seems to work on the PC in the house. It does however keep going over the first toolpath like you stated. On my laptop it makes some crazy crop circles when running the circle toolpath on G56. config pages look exactly the same. I have to run three operations on the mill and wanted a test code. I will move on to the real thing with this outline and see what happens. Thanks for the reply!

[BR549]

It is acutally drawing it correct when cutting as the Zero gets reset each time the Fixture changes. It should cut just fine.

On your laptop look at the IJ settings. Crop circles sound like it is set to abs instead of inc. You can change it with Gcode to make sure it is set correctly on program load.

(;-) TP

[Riley]

I reinstalled mach on laptop and set config just like the pc in the house and the one on the mill, and it works fine. But the pc running the milling machine still wont run it correctly. All settings have been tripled checked and it just won't run it. If I call sub o1 for all three work offsets it is ok. If I change it to call sub o2 for all three offsets it still is ok. If I change it to any combination of o1 and o2......fail. It come up with some crazy toolpath for the third work offset. I even tried calling the offsets in the reverse order. If I take out cutter comp all is good, however that really does not help me much.

[BR549]

HIYA Riley, You were close(;-) Change the G41 to a G42. Also set your tool# 12 to about 0.050"diam to make SURE it clears that tight radius.

After changing those points it runs fine here.

(;-) TP

[Riley]

Well here is where I'm at....both subs are totally identical and as long as I only call one of them the program works fine. If I get really crazy and want to call a different sub then things get sticky. I have included a photo of a program and its matching toolpath, one with all sub calls the same and the second program I asked it nicely to run sub 2 and it makes crop circles. Have tried many many different combinations and the results are the same. 

[BR549]

AH I see you found the known BUG in TComp and  SUBS. It has always been there.  AND there is NO KNOWN way to overcome the error that I know of . Last time I worked on it for 3 weeks straight trying to creat a workaround. NO LUCK

Sometimes you get LUCKY and do not disturb it and everything runs OK but certain combinations of  multi subs AND TC sets it off.

Best to stay away from TC and subs. Subs by themselves run OK. The problem is Mach does NOT carry over some of the positional data from SUB TO SUB and it gets lost trying to apply the new TC. It will eventually find it ways BACK to the proper stop place givin enough room to roam.

(;-) TP

[Riley]

so how does one run cutter comp on different work coordinates? This has to be an everyday occurrence for some people.