I set my Z-zero a little unorthodoxly, but it works consistently, and it’s efficient enough for my needs. I do not have a bit setter. I thought about getting one, but I’ve gotten pretty good with my procedure, and I’m not sure it would save me much time.
To use this method, you will need a repeatable spot (XYZ) that you can go back to on your workpiece. This spot cannot be cut down, so if you are doing a fully caved piece, you would need to have extra uncarved material or use the spoil board as your Z-zero. I use the spoil board as my Z-zero if I’m doing a full carve. Basically you need a spot that is not going to change depth over the course of your program.
Now that we have that.
- Jog XY to your spot that you want to set Z-zero. I make this a spot where I change my bits if possible. (Instead of jogging, I usually run a quick macro in UGS to go back to the same spot).
- Install your first bit, but do not tighten it. Push the bit in all of the way and only hand tighten it using the push button on your router. Just enough to hold it from falling out.
- Jog Z down until your bit is about 1/8"(3mm) above the workpiece.
- By hand, loosen the collet until your bit slides down to the workpiece. You can use a finger to keep the bit from sliding down too fast. This will be your Z-zero.
- Tighten your bit using both wrenches.
- Set Z-zero in your control software.
Repeat this for every tool change.
Your Z-zero will be set at the same spot for every tool change. No guessing with paper pressure, no feeler gauge. Just gently let the bit down to the workpiece, or spoil board, and have a nice consistent Z-zero.