2 or 3 axis dro?

[EddyCurrent]

The measurement you want I think is, 'height of tool over table', so that implies 'machine fixed part to quill'. If it's anything like my overhead router, the head movement is just to get the quill into it's range of travel over the job.

[njhussey]

I'd go 3 axis, I didn't when I bought my Warco Major GH and regret it, I've since fitted a seperate one to the Z axis but it's not as good as it's got a small unlit display....definately go on the quill if you're not CNCing it or the head if you are CNCing it...

[Neale]

I have a Warco VMC with a rise-and-fall knee, so the third axis is fixed to that. I don't use the Z axis anywhere near as much as X and Y, but for setting a cut depth for milling, that works for me. One of the factors that I would think about is whether or not there is a fine feed on the head that you can use to apply a cut. In general, you are probably not going to use the Z readout that much for drilling but will do for milling and that's where the head rather than quill movement would be used. I say that partly because the quill fit in the headstock on my machine is not that good and I prefer to keep it clamped for milling and use the knee (head in your case) to put on a cut.

[Web Goblin]

The quill does have a fine feed as well as power feed which is good but the crank feed for raising and lowering the head isn't very smooth or accurate at all so I would be using the fine feed to set depth for milling.

[Neale]

The quill does have a fine feed as well as power feed which is good but the crank feed for raising and lowering the head isn't very smooth or accurate at all so I would be using the fine feed to set depth for milling.

Sounds like Z axis on quill, then!