Inaccuracy in Z-axis

Troubleshooting the Pocket NC
#1

Hello everyone,
I have problem to mill round part on proper dimmension, i get almost 1mm difference in z-axis.
I mounted reference round part 8mm diameter to check indicated Z-value , setup tool #5 (machine mesured tool lenght offset).

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#2

This is what I get:

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Z-value should be close to 4 mm, but it indicates 3,650mm.
I tried couple times to set up tool again and each time results are very similar.
Is there something wrong with machine WCS or machine made mistake while measuring tool lenght offest offset?

#3

Are you getting different length results when you run the probing with different speeds?

#4

When I do the same measurement in X-axis

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Everything looks ok 5,5 mm -1,5mm(tool radius)=4

#5

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Machine is almost new, worked only 16 hours.

#6

I tried with different speeds, diffrences are the same.

#7

It would be good to measure your TLO manually and compare it to what the machine is measuring. Doing so will help narrow down where the issue lies.

Steps for making the measurement manually can be found in section 4 of this document