Any Concern About Probing Damaging V-Bits?

I know with most end mills damage to the bit is not a concern when probing. But what about with v-bits? The tip on my 30 and 20 degree bits looks fairly fragile - at least when I think about it tapping the aluminum touch plate. But even my 60 degree Whiteside with a true point trends to worry me. From time to time I can actually see and feel a tiny divot in the plate after the probe.

What ipm setting are you using when probing with these finer bits?

Answer is no. Probing doesn’t work as push down process, probing is about shorting incoming voltage with the ground. As soon as makes a little contact it stops movement.

There is posible break on bit tip if you don’t clip on your bit. Clipping to colette or anything delays power contact, would happen. Also bad connection on arduino might cause problems. It’s been years, didn’t see any bit mark on my probe surface yet.
Answer is still No if probe connected and used properly.

Yes I do, what I’m telling is bit does not push the probe, at least on grbl system. Barely touch will make contact with negative and positive to tell arduino to stop immidiately.
My big machine have push probe system, pushes spring loaded plate down to make bottom contact 5VDC to ground twice for bottom surface datum alignement to run profile cut. That is Mach4 Cam on it.
And must use secondary touch plate for engraving or V bits which you use top surface datum, same way runs backwards about and inch as soon as touches to plate.

Just put your flash light on it and wach with magnifying glass. You’ll be amazed.

Ok, you’re right. I think there is no way to tell you this. Besides, if any tip can easily breaks by touching, that is not suitable for carving.

For the 20 and 30 degree bits I have been using the paper method. Was just wondering if it was justified. Have to say I think I’m with Robert here - the tips are so tiny I can’t imagine them surviving much any contact with any metal. Maybe I need a lead cap for the touch plate.

Actually, that might make an interesting experiment. Place a thin piece of lead on top the plate and see if the touch leaves a mark. I have some 1/16" thick lead sheeting back in the shop - think I give it a try.

You can use aluminum foil as your probe surface… Won’t break a tip.

Did some experimenting today. Took a close look at the 20 degree I have been using and although I hadn’t noticed any problem with the cut it is obvious the tip is damaged. For reference the bottom bit is a new one and the middle end mill is a 1/32 which looks huge compared to the V bits. (I have two of the 1/32" and have never been brave enough to try to use them). So Robert is right about broken tips and I will just continue to use it. (actually it is not as bad as this photo makes it look - the light was reflecting back making it look worse than it is.)

Did a probe with the new one into a piece of lead. I use a double tap macro to probe and the faster first touch is a .5 ipm. I left a very small mark on the lead but really light. Close inspection showed no damage. I then decided to go for it and used the aluminum touch plate. I have Charlie’s Triquetra but for this used my alternate plate which is a .5" thick piece of T6061.

Did three double tap probes hitting the plate in different areas. No discernible marks. In this close-up view it appears there was no damage done by the probing. The top bit is the one I used and the bottom is another new bit. So I guess you can get away with probing these tiny tipped bits. Still tends to be a high pucker factor for me…

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