Bad Spindle Evidence?

[toothdoctor1]

I jst milled one in the problem mill. I watched closely the whole time. When it picked up the last bur, the .6mm, there was a small gap between the stop ring and the collet. Pic isnt the best, but on the other burs the snap ring is right up against the collet. With the .6 theres about 3/4 mm gap.
Why could that happen? Its clearly the point of issue. Its then over penetrating what it should while milling.
View attachment 32283

Hey, just curious if you ever solved this issue? I have a VHF Z4 that I picked up second hand. When milling any glass ceramics, it often gives a tool breakage error (new tool, new collet, perfect calibration, software says '20hrs on spindle' but unknown to me)
Mills Vita Cad Temps perfectly (that's basically what i use it for). Never used zirconia. Emax will often give tool breakage error, but just rerunning the same mill without removing the block will result in success. Tried changing to a new collet chuck, same issue. Checked calibration and recalibrated it and still the same (calibration block comes out perfect)
Have the same gap between stop ring and collet chuck, and press down is selected in settings. Just wondering if it's normal?
Thanks!

 

[Car 54]

toothdoctor, that friend of ours passed away a while back. Maybe someone else will help you.

 

[CoolHandLuke]

Hey, just curious if you ever solved this issue? I have a VHF Z4 that I picked up second hand. When milling any glass ceramics, it often gives a tool breakage error (new tool, new collet, perfect calibration, software says '20hrs on spindle' but unknown to me)
Mills Vita Cad Temps perfectly (that's basically what i use it for). Never used zirconia. Emax will often give tool breakage error, but just rerunning the same mill without removing the block will result in success. Tried changing to a new collet chuck, same issue. Checked calibration and recalibrated it and still the same (calibration block comes out perfect)
Have the same gap between stop ring and collet chuck, and press down is selected in settings. Just wondering if it's normal?
Thanks!

if you are seeing no gap prior to milling, but a small gap post milling, then your collet is loosening either due to wear or because it isn't tight anymore. most tool length errors arise when the sensor is detecting a number different from its first measurement by a significant amount.

 

[toothdoctor1]

toothdoctor, that friend of ours passed away a while back. Maybe someone else will help you.

so sorry to hear that, terrible news

if you are seeing no gap prior to milling, but a small gap post milling, then your collet is loosening either due to wear or because it isn't tight anymore. most tool length errors arise when the sensor is detecting a number different from its first measurement by a significant amount.

what about gap prior to milling? slight gap of a mm between collet and stop ring. I'll have to check but I think all burs prior to starting have had that gap

 

[CoolHandLuke]

i don't see that as being problematic unless the gap is growing.

 

[toothdoctor1]

i don't see that as being problematic unless the gap is growing.

Thanks!