# Z axis not accurate **URL:** \ **Category:** Troubleshooting\ **Created:** [August 2, 2015, 7:10pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414 "2015-08-02T19:10:41Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![AaronGnade](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@AaronGnade](https://community.inventables.com/u/AaronGnade)\ **Post date:** [August 2, 2015, 7:10pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/1 "2015-08-02T19:10:41Z")
I have a xcarve 1000mm with acme rod on the z axis I’m trying to do a project in easle and the z movement is not accurate I am trying to just cut .006 in off the top of anodized aluminum and it is cutting almost 1/16 inch per pass. I have the macine set up for acme rod any ideas. ---
**Author:** ![NickCook](https://avatars.discourse-cdn.com/v4/letter/n/82dd89/32.png) [@NickCook](https://community.inventables.com/u/NickCook)\ **Post date:** [August 2, 2015, 7:14pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/2 "2015-08-02T19:14:48Z")
Make 100% sure that you have acme rod and try redoing the setup machine tutorial in easel. If all else fails try adjusting the current potentiometer for the z axis. It almost looks like you misplaced the decimal 0.006 instead of 0.06 ---
**Author:** ![RobertA\_Rieke](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/roberta_rieke/32/32723_2.png) [@RobertA\_Rieke](https://community.inventables.com/u/RobertA_Rieke)\ **Post date:** [August 2, 2015, 7:15pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/3 "2015-08-02T19:15:40Z")
It could be the Z pot, but have you tried calibrating the Z axis? As in the number of steps per mm? ---
**Author:** ![AaronGnade](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@AaronGnade](https://community.inventables.com/u/AaronGnade)\ **Post date:** [August 2, 2015, 7:20pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/4 "2015-08-02T19:20:06Z")
Not sure how to do that ---
**Author:** ![AaronGnade](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@AaronGnade](https://community.inventables.com/u/AaronGnade)\ **Post date:** [August 2, 2015, 7:20pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/5 "2015-08-02T19:20:45Z")
No .006 is correct ---
**Author:** ![RobertA\_Rieke](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/roberta_rieke/32/32723_2.png) [@RobertA\_Rieke](https://community.inventables.com/u/RobertA_Rieke)\ **Post date:** [August 2, 2015, 7:22pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/6 "2015-08-02T19:22:34Z")
Here’s a forum post that links to a video about calibrating the axes. I found it very useful, and modified it to calibrate my machine. > [@Steps/mm Calibration](https://community.inventables.com/t/steps-mm-calibration/10705): > > I found this video through the X-Carve sub-Reddit ([r/X-Carve](https://www.reddit.com/r/XCarve/)) and thought it might be helpful! [[X-Carve DIYCNC Router - Calibration of steps/mm] ](https://www.youtube.com/watch?v=TzkoMbb9pO8) ---
**Author:** ![AaronGnade](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@AaronGnade](https://community.inventables.com/u/AaronGnade)\ **Post date:** [August 2, 2015, 10:14pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/7 "2015-08-02T22:14:06Z")
The video makes sense but in easle where would I make those adjustments. ---
**Author:** ![RobertA\_Rieke](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/roberta_rieke/32/32723_2.png) [@RobertA\_Rieke](https://community.inventables.com/u/RobertA_Rieke)\ **Post date:** [August 3, 2015, 12:07am UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/8 "2015-08-03T00:07:56Z")
It took me a while to figure it out, this information will be in the calibration video I’m making. - In Easel, go to Machine-\>Advanced-\>Machine Inspector. Settings $100, $101, and $102 are the x, y, and z steps/mm, respectively. Write down their values. - Calculate the new steps/mm using the equation in this picture (X axis for my machine): - In Machine Inspector, there’s an entry screen called “Console”. Enter the new setting like I did in this picture (again, X axis for my machine): - Hit Enter, and then hit the refresh button over on the right of the settings section (double arrow). - Verify the setting you changed is actually the new value. - Close Machine Inspector and refresh Easel. - Open Machine Inspector, and verify the setting is still what you want it to be. You should try to make the calibration measurement again, and may have to tweak it a couple times for each axis until you’re happy. It took me 2-3 rounds of measuring and adjusting until I got my X and Y axis within .1mm over 500 mm, using a large scale. It took 4 rounds to get my Z axis within .0005" over 1" using a dial indicator. I haven’t seen any documentation to explain any of this, so it’s all new to me too. I just figured it out 3 days ago. Hopefully my calibration video specific to Easel will help others out in the future. Let me know if you have any more questions. I can’t promise any answers, but I’ll let you know if there’s anything I can do. 😄 Rob ---
**Author:** ![AaronGnade](https://avatars.discourse-cdn.com/v4/letter/a/96bed5/32.png) [@AaronGnade](https://community.inventables.com/u/AaronGnade)\ **Post date:** [August 3, 2015, 10:29am UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/9 "2015-08-03T10:29:12Z")
Thanks I will. Aaron ---
**Author:** ![DavidSohlstrom](https://yyz1.discourse-cdn.com/flex009/user_avatar/community.inventables.com/davidsohlstrom/32/77077_2.png) [@DavidSohlstrom](https://community.inventables.com/u/DavidSohlstrom)\ **Post date:** [August 3, 2015, 2:55pm UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/10 "2015-08-03T14:55:56Z")
I think if you check on stepper theory. You will find that it is not possible for a stepper to move an odd number of steps stepper like whole numbers. ---
**Author:** ![MatthewWatson](https://avatars.discourse-cdn.com/v4/letter/m/2acd7d/32.png) [@MatthewWatson](https://community.inventables.com/u/MatthewWatson)\ **Post date:** [November 16, 2016, 7:40am UTC](https://community.inventables.com/t/z-axis-not-accurate/11414/11 "2016-11-16T07:40:39Z")
Take the inverse of this number and divde my microsteps and you get mm per microstep. (1/38.88306)/8 = mm per microstep.