Hi,
would you please expand on what you are trying to do.
'Homing' has a very different meaning to 'Zeroing an Axis'.
The machine is natively in machine coordinates, its the only coordinate systemm the machine understands. If you 'Home' a machine it will drive in turn
to each of the home switches in turn and zero the MachineCoordinate of each axis (or offset by a given amount per your programming). This is the machine
'Home'.
Its common, not actually required, but common for the machine Home to be with the X axis hard to the left, the Y axis hard to the front and the Z axis right at the top of travel.
Most machines have limit switches at each extreme end of travel of each axis and thus three of those limit switches can also be used to define the machine Home.
There is nothing to stop you from having the machine Home elsewhere, for instance you could have three home switches that are located in the middle of each axis.
All that the machine is interested in is that there is a single well defined and absolutely repeatable location where the machine coordinates are 0,0,0
Note that the only way to set the machine coordinates is to use a Homing procedure, either with home switches, or you can use the 'Home in Place' option.
I suspect its that Home in Place option that you are trying to use and its confusing you.
The other procedure is 'Zeroing an Axis'. Lets say you have already 'Homed' or equivalently 'Referenced' your machine, where its gone right to the top of the Z axis, X axis to the left
and right forward of the Y axis and there established the machine Home of 0,0,0 in machine coordinates. Now you put a piece of material in the vice roughly in the center of the table.
You now jog your machine to the lower lefthand corner of the material and hit <Zero X>and < Zero Y>. The X and Y axes DROs will now read zero. This is the Work Coordinate position.
If you toggle to the machine coordinate DROs you will see that the Work Zero is X=256.87mm and Y=341.54mm. That means that the Work Zero, ie the corner of the material is
256.87mm from the far left of the X axis and 341.54 mm up from the bottom of the Y axis. That's ll very well, but it does not help you especially, what you want to do is drill a hole
in the material 42mm in X and 21mm in Y from the corner of the material. If you flip back to the WorkCoordinate DROs now you can jog to X=42 and Y=21 and drill your hole.
The fact the the machine uses machine coordinates does not really bother you, all you want to do is drill the hole in the right place.....its up to the machine to keep a running tally
of the machine coordinates, and the machine does that no trouble, where that would hopelessly confuse you and I after a while.
The important point here is that while you can zero a work coordinate position and otherwise manipulate them what you CAN'T do is set a machine position at will, that CAN ONLY
be done by one of the two Homing procedures, either 'Homing' ('Referencing') to home switches or 'Home in Place'.
Craig
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