Tool breakage Detection thinks tool is broken when it isn't.

[Ryan at Sparrow]

My machine (a newer EC400) has been running with tool breakage detection for many months now. It has saved us many nights of runtime. I love it. Lately though I am having issues with the machine thinking a tool is broken when it is not. I might get to work in the morning and see the machine has stopped because it thought a tool was broken, changed to its backup tool and thought the backup tool was broken too. I only have 2 tools so after that it just turns off.

I can't tell why it would be doing that. I have the tolerance on the detection as plus minus 2 thou which is a lot. I want to say its a chip on the probe as it comes up but I've personally watched a chip come up on the probe and the tool kind of just kicks it off on the first touch and then measures fine on the second touch. The tools themselves do not have chips on them. We also clean the probe box out often but there's really not THAT many chips in there.

It is such a long shot, but the only other thing I can think of is coolant droplets falling from the ceiling and hitting the probe during the measurement cycle. What would the chances of that be?

I should mention that I checked the probe with our tool standard and it is within .0002, so I'm happy with that. I'm thinking about making a little brush or something mounted to the box so that it wipes itself clean when it extends but that also might collect chips itself. If the coolant dropping onto it can trigger a false break then I would be willing to machine or fabricate some sort of shield to mount to the probe.

I also wonder if there would be a way to double check tools. Let's say the machine thinks a tool is broken, maybe it could grab an air blast tool and clean the probe with air / coolant and then regrab the measured tool and recheck it. If it still measures out of spec then actually expire it. Any thoughts on that? Thanks in advance!

 

[Finegrain]

I have the tolerance on the detection as plus minus 2 thou which is a lot.

Is it though? You're trying to detect tool breakage, not tool thermal growth or something like that. Try .02". If the tool is really broken, it'll be off by a lot more than that.

Regards.

Mike

 

[gustafson]

my Brother w/blum does this
chip in the drill that falls off right after it touches

 

[Ryan at Sparrow]

Is it though? You're trying to detect tool breakage, not tool thermal growth or something like that. Try .02". If the tool is really broken, it'll be off by a lot more than that.

Regards.

Mike

You know, you're right. I will try that. As a matter of fact a tool has actually only been broken maybe a small handful amount of times in the last 6 months. It has falsely alarmed out more often than it has caught a broken tool lol. I'll do like .02" or .05" and maybe that will compensate for a chip. I also wonder if I can DPRNT the measured length so I can see exactly what the probe is seeing.

 

[EMTech]

Is this a physical touch Renishaw probe?
Or is it a laser non-touch probe?

 

[Digital Factory]

I set my breakage tolerance at 0.020" on DMG Mori horizontals.