What is the point/How Important is that circle in the Touch Probe?

So I am new to the CNC world. I Just got my machine, and I figured I’d get intimate with it, by milling up my own Touch Probe. But I have a few questions.

  1. How important is that circle on the touch probe? Whats its purpose, I just don’t get that part. I mean I understand that you want to center the bit on the circle, just don’t get why. Im guessing its to make it stupid proof or something?

  2. Does the thickness matter? As I understand it the Probe works on a macro, so you just connect the wires, press the button and it knows that the probe is a specific thickness. Well Can I reprogram that macro based on my own dimensions, or do I need to actually copy pasta the OF probe.

  3. This part is more so geeky. I understand that its essentially the closing of the circuit that makes the controller understand that the probe is at the desired position for zeroing. How does the controller know this? Is 1 pin a small voltage? Is it running a continuity test? This really serves no purpose other then to feed my urge to understand things lol.

  1. The circle is the the optimum point to get to both X and Y touch off points after zeroing Z. If the bit is say in the center of the probe plate the bit would crash into it after completing the Z probe step.

  2. The 1F probe thickness is pre-programmed into the 1F axis probe macro. It is possible to adjust those parameters in the controller (based on your specific probe’s actual dimensions). You can find that procedure discussed elsewhere on the forum.

  3. Yes, by nature the system uses a small voltage to establish continuity.

The probe is not rocket science but 1F’s probe is well designed and very accurate. I feel that it helps reduce some of the guess work when troubleshooting operational problems.

Hopefully others can provide more accurate detail if any of this in error.



You are spot on with all of your answers…

One other thing to add, if you go with a properly grounded spindle, it was my understanding that I/you can get rid of the magnet attachment step… I will confirm once I test, hopefully this weekend.

properly grounded? like running a ground from the router to the the touch probe instead of the magnet? sorry for the dumb question. just curious, because i want to do this.

When the spindle is properly grounded, i.e. pin 4 to ground and the chassis of the spindle is grounded to the the internal pin 4, then you do not need the magnet for the touch probe. The chassis of the Makita router, by itself is not grounded, it only has the 2 prongs(at least the US version).

Here is a good/short thread/explanation… Touch probe/Spindle - What did I do wrong?

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thanks, gonna have to attach it somewhere else,the 4th pin on my Chinese wasnt grounded internally.might have to attach it to the screws on top. thanks again

Which Chinese version? I got the HuanYang. You may be able to remove the cap/top and just put in a jumper from the chassis to the #4pin on the spindle. You want it to be grounded no matter what…

BTW I bought a ground bar for my VFD from corvetteguy, to eliminate the need to try to land several wires on the small Earth Ground screw/post in my VFD

sounds like we have same vfd. the 375-400$ one? a ground bar is nice idea. i have a few of those bar laying around from my boat parts. I will drain my spindle and open it up and run a jumper. something about pimping the 1f out is fun, lol. plus I prefer not to worry about having to spin off a magnet by accident.