I usually eyeball my end mill to the front left corner of my stock, usually carefully rotating the mill by hand to make sure it’s centered over my intended origin. Then I realized I have one of these, which comes apart to reveal this other pointy thing. Turns out the pointy thing has a 1/8 inch shaft, so it can go into my Nomad’s collar and when it does, I can see EXACTLY where it’s pointed and thus were my spindle is located. Then I set my zeros. Anyway, thought somebody might find this helpful. 'Course, once those new touch plates from C3D come out, this may be less relevant.
That’s a nice solution, it’s nice to see you can get the point separately.
I use a stub of a 1/8" TIG electrode sharpened up to a fine point.
Be careful with the TIG electrode. If the spindle starts, bad things can happen. I have a little piece or three of thoriated in my chest from grinding using a handheld drill to spin the electrode during sharpening back before good tungsten grinders were available. No risk from them staying put, but risk to remove them, so they stay. A bad touch off, even without the spindle running, and still throw chunks.
Hm. I used a nice tungsten grinder to sharpen it. It’s also very short, about 3/4 OAL, most of it ends up in the collet. I’m surprised you woul dhave fracture problems with something this large - 1/32 sure. Thanks for the info!
Any flaw in the surface will lead to a crack if there is significant force. If the spindle is run, even he lowest speeds will likely cause chunks to let go from the point. A tungsten grinder, properly used, will give a much better finish than a bench grinder, but there are still microscopic flaws. It is very brittle. I have used tungstens for scribes and trammel points, but would, personally, never put one into something that could spin under power again.
A v-bit or engraving bit has a nice sharp point for setting X and Y. Then set Z with the actual tool and the paper test.
Or use the Triquetra XYZ probe, which works great with UGS. Or wait for the active Carbide probe, which I’ll prolly buy when it is available.