# Z either losing calibration mid cut or too much backlash in lead screw? **URL:** \ **Category:** General Chat\ **Created:** [June 17, 2024, 11:59pm UTC](https://forum.avidcnc.com/t/z-either-losing-calibration-mid-cut-or-too-much-backlash-in-lead-screw/3302 "2024-06-17T23:59:35Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![DavidsPostProcessor](https://avatars.discourse-cdn.com/v4/letter/d/76d3ee/32.png) [@DavidsPostProcessor](https://forum.avidcnc.com/u/DavidsPostProcessor)\ **Post date:** [June 19, 2024, 9:05pm UTC](https://forum.avidcnc.com/t/z-either-losing-calibration-mid-cut-or-too-much-backlash-in-lead-screw/3302/2 "2024-06-19T21:05:25Z")
Welcome to the forum. I haven’t had this particular issue, but I’ve seen it discussed multiple times on the forum and it almost always comes back to one of a few things. So far I haven’t seen that symptom due to backlash or calibration - they would be the least likely culprits. Here’s a couple from the Related Posts suggestions: > [@Lost Z-Axis By 5/8" In One Movement?](https://forum.avidcnc.com/t/lost-z-axis-by-5-8-in-one-movement/1495): > > I was cutting this piece and partway through it completely lost the Z, and was ‘zero-ed’ about 5/8" below where I zero-ed it (relative to the bed). The collet was contacting the material, so it was not a case of the bit slipping. I stopped it on the third burnt hole in the picture and re-zeroed and restarted and it did not happen again, so I do not believe it is an issue with the G-code. Any idea what could have caused this? Machine : PRO60120 Spindle : 3HP Bit : 3/8" Compression Depth Of… > [@Z axis problems](https://forum.avidcnc.com/t/z-axis-problems/1092): > > I was running a surfacing program and didn’t like the way it was running so I stopped the program and since that point my z axis isn’t running properly. The z axis is making some not so great noises and really only wants to go down. I press the z up and it jumps down but if I hold the z up it will go down then go up. I love to hear your thoughts. Machine is a Desktop Pro 24x24 with plug and play NEMA 23 electronics Troubleshooting to this point. - reset machine and computer - Checked conn… Good luck and hope you get it cutting like normal again. --- _[View the full topic](https://forum.avidcnc.com/t/z-either-losing-calibration-mid-cut-or-too-much-backlash-in-lead-screw/3302)._