Re: Puzzled

[Dan Falck <dfalck-at-sprynet.com>]

Ian,
The way that I do it is to touch off on the part with the cutter -while in
jog mode.  Then go into MDI and give it this command:
"G92 Z0.0"
This tells the control that you want Z zero to be right there.

Then, while still in MDI, move the cutter up with:
"G00 Z1.0" or "Z.5" or however high you need to go to clear clamps
etc...(I'm using inch units)

You can also use the tool length offsets with G43.  If you set up your
tools prior to running a program, anytime you call off a Txxx G43, the
control automatically knows where Z0 is. So far, with no quick change
tooling, I just use G92 Z0.  

If you have a knee mill with the servo on the knee, it's easy to set zero
by lowering the quill manually onto the top of the part and then giving it
a G92.  

Dan



At 02:37 PM 2/5/2000 , you wrote:
>Hi,
>
>Am I missing something or is it not possible to reset the axis figures to
>zero in EMC without physical home switches?  If not it would seem to me to
>be a very useful addition, particularly on the 'z' axis.  I am thinking
>particularly of the way in which I am likely to use a lot of dental burrs in
>milling small parts or other sundry small and probably surplus milling
>cutters. Setting a length for these would be difficult if it has to be done
>as a measurement but, if the cutter could just be jogged down until it
>touched a point on the work, perhaps indicated by the completion of an
>electrical circuit lighting a bulb, and the display for that axis then
>zeroed and instructed that that is the home position for that axis, it would
>make setting up a whole lot easier.  I hadn't realised that this function
>appeared to be missing until I was playing about with backplot today and,
>after aborting a run part way through, found that I couldn't then home or
>reset the axis displays to zero without shutting down the program and
>starting again from scratch.
>
>Ian
>
>--
>Ian W. Wright
>Sheffield  UK
>