Tool height compensation, similar to how XY probing is used for tool radius compensation. For me, it's the final piece of the puzzle to really bring the tool library to its full potential.
The library has the parameters of each tool, but only the radius is used with the probe. I can probe a corner (or other reference feature) and set the cutter location in XY space. However, I still have to touch off, or take a cut, on the top of the part, then measure to determine where the end of the cutter is in Z space.
Which I suppose is fine for roughing out a bandsawed piece of stock, but what if I want to take a cut referenced from an already machined face on an unknown part? It would be much easier to be able to probe that surface, set that as my Z-reference, select a tool from the library, and have the cutter height automatically factored in, the same way cutter diameter is.
Or Z-probe the bed of the vise (or the top of a parallel), and set THAT as Z-reference, and be able to work to a dimension in the Z axis. Maybe have a "Desired Z Value" dialog in the probing menu, so you can tell TouchDRO your desired Z dimension, probe the vise bed, and work to zero.
I suppose the UI could be a standalone "Tool Library" button, which has a list of all the tools, the graphical representation of tool position (like in the Radius Compensation dialog), and a "Desired Z Value" box. Maybe incorporate a duplicate of the "Indicate Workpiece" dialog as well, so it's all under one button/dialog. Probing would establish the datum of X, Y, and Z, and selecting a tool would apply the necessary offsets. I feel like this is the best option.
The existing "Set Z Reference" and "Tool Height Compensation" dialogs could remain, for people that don't use the tool library.
Also... Preferably the probe height, and tool heights, would referenced from the spindle nose. This way, tool heights are determined relative to a common datum, which makes it easier to measure tool heights on a surface plate, rather than always having to do it in the machine.
I feel like TouchDRO is basically as close to CNC as manual machining can get. Except with a human reading a print and turning the screws, instead of gcode and steppers/servos. Meat-servos, if you will.
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