Quote Originally Posted by AndyUK View Post
Z-Axis probing is a complete game changer, I really don't know how I went without that initially. So simple to setup as well; just have a 0V clip on to the tool (I've cheated and run a dirty 0V line to the spindle holder), and a second "Probe" line from the UB1 to a block of aluminium. Setup one line in UCCNC, and you can use JSP (jog safe probing) immediately which is great for X&Y. Measure the block thickness and quickly google a tool height setting macro, and within 10mins you'll have perfect and automated Z height setting. I'm now looking into having a permenant block in one corner and letting it have a bit more automation on those tool changes, but one step at a time.



Thats a great idea - I've shyed away from anything contactor/relay like on the power side of the VFD, but theres nothing to stop me putting a relay on the control logic side that would drop it into a safe state. Still not completely foolproof because short of powering down the VFD at every tool change theres always some risk the high quality chinesium in the VFD will go haywire....
Thanks Andy, I will read up on the UCCNC probing.
I take your point about the chinesuim (lovely word by the way. I'm rather proud of having invented the word 'polycrapoline' to describe the cracked-within-weeks material used in some HV breakers I had the misfortune to work on many years back). It's for each of us to decide the level of risk we are willing to accept in our home workshop.

I was once very shocked to find an interlock system in a former employer's premises which, when made 'safe' left an HV power distribution transformer able to be back-fed if a microscopic transistor inside a PLC microchip went short circuit and decided to power an external relay which would close an HV breaker which was NOT included in the electromechanical interlocking. The risk I'm taking in not powering down the VFD every tool change is similar but the consequences, though potentially serious, are not guaranteed fatal and I only touch the sharp tool itself for a few seconds.