There is probably something simple I am missing here, but I would like to rename the "A axis" to "U axis" throughout the system.  Is there a simple way to change the letter of an axis in Mach 4?

Hi,
not quite sure what you're hoping to achieve. Even if you did successfully change Aaxis to Uaxis throughout
your Gcode will still have to use 'A' unless you can change how Mach interprets Gcode.

It is possible to relabel the buttons and similar so they would display 'U' instead of 'A' but the underlying
code and actions would remain Aaxis actions/signals.

Craig

Craig - That is what I want to change.  The axis is technically the "U" axis.  It is an auxiliary axis that runs parallel to the X axis.  I have already changed the buttons etc...  but then the G-code still needs to see "A".  I would like to change the axis letter globally throughout the system so it is recognized as "U".

I don't believe that is possible.... you have ABCXYZ.... all gcode works on that.... some axis can be slaved to others...

Why not just change the gcode to one of the isable acceptable letters?

I can do that, but I just wanted to follow what seems to be the machine tool industry standards for axis designation.  I have used a lot of different machine tools and every single one has followed this. 

Attached is a screenshot from http://www.globalspec.com/reference/76593/203279/multiaxis-machine-configurations

The main spindle axis is typically the "Z" axis.  "X" is perpendicular to the "Z" and is usually (not always) the longer of the two between "X/Y" if they have different travels. 

By knowing the cartesian "XYZ" of a machine tool you should be able to point out "ABC" and "UVW" without guessing.  If you run a lot of different machines on a regular basis, it's nice to have them follow a standard axis designation to avoid mistakes made due to sloppy/random axis assignments.

I have way less experience than you.

But, having a quick look at the comparison document I found, M3 + M4 will only control 6 axis, hence the normal practice is to slave an A, B or C to an X, Y or Z should you have a parallel axis.

http://www.machsupport.com/wp-content/uploads/2014/06/Mach%20Version%20Differences_doc_a9.pdf

Pardon my ignorance, but why would you want to operate the U axis any differently to the other parrallel axis (other than if you were squaring it up)?

A typical application of a UV running parallel to XY would be for taper cutting on a wire EDM machine.  My machine is a grinding machine and "U" controls the wheel head outfeed.

This may be what is called an out of band axis (or axes), sorry out of my depth.... sure a knowledganle person will come along, I'll get the popcorn and learn, Thanks for taking the time with the explanation.

Speaking out ignorance ..............

I would say that Mach controller is designated to industry standard for a 6 axis machine with primaries / rotary  of  X/A, Y/B, Z/C.
If it was 9 axis then it would have a supplemental secondary axes of U,V,W and thus related  X/U/A, Y/V/B, Z/W/C were U,V,W
are parallel to X.Y.Z.

dah........, only know what Smid  says,  

no pop corn left....going for the chips
RICH

Rich,  I would have to respectfully disagree unless ABC are forced to rotary axis. UVW are linear.

Examples:

1.  A typical CNC horizontal boring mill table rotation is designated the "B" axis because it's rotational axis is parallel the "Y" axis.  The "W" axis is the linear movement of the actual protruding spindle parallel to the "Z" axis.  The "C" axis is rotational about the "W" axis





2.  A 4axis wire edm machine that can cut tapers has a UV that are linear and run parallel to XY





3.  In a VMC, when mounting a rotary that's rotational axis runs parallel to the "X",  It is designated the "A" axis.
     If the rotational axis is parallel to the "Y" axis,  it is designated the "B" axis.