I'm confused about the Safe Z thing. Seems to me that it'd be a good thing to have as I can then simply hit my "Safe Z" button on the controller and have the spindle move to a in good height to change tools... but how do I set the Safe Z in Mach 3?

I've found a "Global Settings" window under the Config/Safe_Z Setup.. but don't understand what the settings mean/do. Seems like the most important one is where you enter the Safe_Z amount. But what is that amount in reference to? The table? Home position? Soft limits? Is is negative or positive from these?

I guess I'm really confused about machine and work coordinates as the DRO's don't say which they are.

BTW, I just got this great CNC controller (pendant, mouse, whatever the thing is called?) http://www.randyray.com/TxMicro/ which is the reason why I'm now keen on getting my CNC setup together better. Check it out - all you do is plug it in and it works. No software, no batteries. Pretty slick for $225!

-- Rich --

The DROs can display either Machine Coords or Work Offset Coords. Usually they display the Offset coords but that depends on whether you have the Machine Coords button active or not.
 Safe Z can be set up to work off machine coords and that is the way I have it set, I have mine set to -5mm. If I press the Go To Zero button the Z will move up to -5 (machine Coords) the X and Y will then move then lastly the Z will move back down to the Offset zero. There are a few other instances where this happens such as if you are doing a Run From Here move.
 If you set up the safe Z as a work coords move it will go up  from where you are to the position you have set.
 If you set up using the incremental it will move that distance up from whichever point you are presently at.
 Safest I think is the Machine Coords as you always know exactly where it will go to, but thats just my opinion.
Hood

I've always wondered how it worked, not been bothered enough to look into it deeply but nice to have my suspicions confirmed.
I did think it was in reference to work coordinates so I set mine to +5mm, no wonder it went AWOL when I tried a run from here, so I did think I'll have to check but never got round to it.

Just read that back to myself and it sounds kind of weird, not going to write it again though

Steve