Problem- Is there a way to auto zero after a manual tool change?

[shobley]

Hi,

I've been searching the forum for an answer, but since I don't really know exactly what I'm looking for I've not had much luck.

(Using the latest Mach3)

I've been doing manual tool changes on my router. They've been working out OK, but the process is *really* manual and I wondered if there were G-code instructions that could speed things up.

My tool paths are from 0,0 - but quite often I have a large panel of material and reset the origin to a vacant portion before starting to cut. I also have an X/Y home sensor set to the "true" 0,0 location of the table.

1) So I cue up my tool path, write down where the new origin is, reset to zero and begin to cut.

2) Once complete, I do a tool change, re-home the gantry then issue manual G-Code to move to the position of my 'new' origin defined in (1) and start cutting the next path..

3) so on and so on.

Is there a G-Code instruction that could automate any of this? Like "find home, and reset to zero"? This would speed things up a bit.

Better still:

1) store current location,
2) zero,
3) cut,
4 pause <tool change>
5) find home,
6) reset to zero
7) goto location stored in (1)
8) zero

I don't know if there's any provision for storing/recalling reference points in G-Code - anyone know if it can be done?

Steve

[mcphill]

Sounds like you may want to use work offsets? Look up G54-G59 (range may be larger). G54 also has a ton of sub addresses - G54.1, g54.2, etc.

[shobley]

Hey thanks for the tip.

So I started to read about G54/G92.

It looks like these can be used to set the global (g92) or one of the fixture (g54 +) offsets that are always in use, but nearly all the time are set to 0 0 0.

I'm still trying to figure out how to use this to store a position and then move to it.

I guess the fixture offsets could be preset, then you just bring them in and out and select 'home' to move to a preset position.

Is there any way to load one of the offsets with "current position"? All I see are using numeric literals, not variables.

[ger21]

You can do all this with macros. There are probably several ways to do it.

1) easiest way would probably be to add a button and DRO's to the screen. Click the button, and it would write the current X and Y positions to DRO's, where they can be retrieved later. I believe there are variables available to store data in using macro's, but documentation on them is sketchy.
2) You can incorporate the zeroing into the macro above.

Look at the Big Tex macro's for auto zeroing after a tool change.

4-8) This can all be done in the M6 macro.

If you watch the video on my site, I use modified versions of the Big Tex macro's in my M6 to auto zero after a tool change. With a macro, you can do just about anything you want.