I had been having problems zeroing my touch plate. While trying to zero a 90 degree “V” care bit from Freud, I could zero one axis but not the other. It wasn’t always the same axis. Sometimes the “Y” and sometimes the “X”. Then it occurred to me that the axis that I had problems with was always the painted side of the bit. Freud paints their bits red and that paint, when touching the touch plate, seems to prevent the circuit from closing and just pushes my work right out of it’s clamps. It does not happen when the bare metal edge of the bit touches the plate, just the painted parts of the bit. So I have ordered two “V” caring bits that are hopefully without any paint coverings. I have no such problems with end mills which, of course, have no painted surfaces.
You could take the paint off the Freud bit or pause the router and adjust the position of the bit so that the cutting edge makes contact and then let the zeroing play on. I’ve had “issues” with V Bits and zeroing myself and now I just do it manually for my Vcarve bits.
When you’re zeroing the X and Y you’re only telling UGS where the center of the bit is, so it’s a lot easier to use a straight bit, or a piece of 1/4" drill rod which has a very controlled diameter, to set the X and Y, then switch to the V bit and set the Z.
I did have issues with zeroing V bits, until I followed the instructions that Bill is setting out here. No problem now.
One thing to be aware of when centering V bits. You should always use the end of the carbide and turn the bit in the collet so it hits the block so it is measuring the same distance off the block from both sides. Otherwise the measurement will be off and it could screw up your carve. I know its a small thing but better safe than sorry.