I'm stuck trying to navigate the whole offset thing.
Is there a better way of thinking about this?
I would suggest that you use a single industrial recognized source to gain understanding of how to set up a machine and
programming techniques. One book that covers it all is Programming Handbook by Peter Smid. It will save you research
and reading time. Supplement the handbook with the mach manuals ( Mach4 agrees with Smid and is Fanuc based
but Mach 3 has a similar / different dialect of code ).
Some info:
- Once the software controller "Mach" has the machines pyhsical location ( Machine Coordinate System) defined the it
can properly use defined work / fixture offsets, tool offsets, and Gcode for CNC.
- Work Offsets ( Work Coordinate System ) / Fixture Offsets
There are many....in Fanuc and Mach there are six work offsets G54 to G59 and then the code changes for additional
offsets namely in the form of G54.1 P( offset number ) but in Mach3 it's ( G59 P(offset number) ).
The work offset is a distance from a machine coordinate / home / referenced point to the Program zero.
The program is the gcode instruction to do machining and has an origin / zero reference point.
? So what is you program zero related to? Fixture location or the actual work pieces mounted on the fixture?
So your thinking / how you setup / how you program can change depending on how you answer the questions.
Consider,
Five duplicate pieces located on a fixture, and if multiple fixtures are used the fixture itself provides for repeatable
location of the pieces on the fixture and additioinaly the fixtures alll go to a repeatable location on the machine.
Thus only 4 work offsets required, G54, G55, G56, G57, G58 and they don't change from the referenced machine
coordinate.
Now if you deviate from the above, variable fixtures and or piece location then you make things more complicated
for no good reason. Rather than production mode you end up with doing multiple setups.
- G52 is a local offset from the current work offset. It proivdes for the ability to cancel the local offset and not affect the
the current work offset. Additonaly it proivdes for convienience in programing. It was not meant as a replacement
for the G5? work offsets. See the Smid book for details.
Frankly the only time I have used it is to provide a temporary offset so a tool could be adjusted for the pre-compensated
gcode from LazyTurn.
Times have changed and there are a lot of programs that produce good code at a reasonable price and inport dxf
drawings.May want to look into Cambam.
Consider using the master tool concept and providing for it.
RICH