[smokediver576]

Hi - Let me try and explain. I think I see what you mean. A NC lathe is different to set than a mill. Usually three stages:

- Set up the tools mechanically

- Set up the work and tool offsets in X and Z and the heights or Y if you want to call it that

- Set the tools cutting to code commands

I split it into three stages because it is easy to think there is only the first two - that's how it would be in a perfect world. But if you just do the first two stages on a low cost lathe with say a probe fixed in a collet or chuck , the parts will not be accurate. You will then need to measure and tweak the offsets to get eg accurate diameters.

Eg with each tool the X offset is not just a WCS, it is effectively also a X tool offset, and this sets the diameter.

So what I am saying is given this final stage is required anyway, then you might as well set the tools less accurately via a quick more basic setting tool, then tweak the parts to get the final accuracy.

Hope that makes better sense. Cheers Cliff

Hey Cliff,

Would it be possible to apply a mathematical "variable" say one for aluminum and one for 304 stainless steel as an tool offset adjustment? Would require some testing to set up the recipes but I think it's doable. Example: Let's say I have a 1" diameter test rod mounted in the chuck. I come down in X+ and touch off on the rod stock. My offset to enter into the tool setting tab would be X +1.0". Now that does not take into account the tools bite or part/table/other flexes. So we do a test cut at 0.090" and it actually measures .095". We now have a .005" variable to apply to our original 1.0" offset. So in the future, for this material I would use my 1" test rod, come down and touch off on the rod and enter 1.005" into my tool offset tab. To be clear, I've not proofed out this theory so I may be way off base. But I use a similar method on the mill.

The general idea is to get the tools rapidly setup to within say .001" to .002" and then dial them in with the wear offset tab. I have to do the same with my mills if I'm trying to hit a super tight tolerance.

The nice thing with the lathe is that your X position for your work is always in the same spot (or at least it should be). Once your tools are shimmed, your Y position is set and does not apply to your work piece. That leaves the Z position to set for your work piece.