My bad, jog the machine to where you want to call home.  Z up all the way on a router and click the Ref. all home button on the run screen right beside your zero dro buttons.  The leds around the zero buttons will turn green once your machine is refrenced.

Brett

I may be way off target here, but if it was me I would also fit a short sleeve (clamp ring) over the ball-screw so it mechanically cannot move the axis far enough to loose the bearings etc. just in case the set limits are accidentally overridden. 

Tweakie.

Spot on as usual Tweakie.  Thanks!

Brett

There is an over travel software limit that you can set in Mach3 so that it will not travel past that point going down.

(;-) TP

Thanks for the input guys!

Brett, thanks for your patience with my lack of knowledge. I watched the tutorial on Homing last night and learned two things...first is that my table has not been set up properly, and secondly, to do so is simply beyond my current capabilities! I do plan to mess with it again today.

Tweakie, thanks for suggesting this option. Considering my statement above, it may be the way to go.

TP, this looks to me like my best simple option to achieve what I want to do. Would you, or someone explain the steps required?

Thanks to all. I have another question but I'll wait until I get my z axis issue sorted out.

Happy St. Paddy's Day!

Bob

Go to PORTS and PINS, Mill option .

Left side near top , Z inhibit, check the box and set the lower limit for Z.

Mach3 will now stop at the lower limit you defined. I believe there is also a button on the main mach3 screen lower center above error line.

NOTE: I JUST looked and on the main screen lower center just above the status line is the Zinh on/off button AND the DRO to set it

It works here OK, (;-) TP

Thanks TP!