# Replacing polymer bearings on the X axis on the Mini

**URL:** <https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670>\
**Category:** LulzBot Mini\
**Created:** [July 1, 2016, 2:45pm UTC](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670 "2016-07-01T14:45:43Z")\
**Posts on this page:** 6\
**Page:** 2

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**Author:** ![mhristau](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.lulzbot.com/mhristau/32/9696_2.png) [@mhristau](https://forum.lulzbot.com/u/mhristau)\
**Post date:** [December 16, 2019, 11:54pm UTC](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670/21 "2019-12-16T23:54:21Z")

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Thanks  
Have some 8mm hard steel shaft material ordered. I’m not finding a dimensioned drawing for the Mini2 bushings. Am I correct that roller bearings are not available as drop in replacements? Nor would drylin linear slide bearings: IGUS RJZM-01-08 ??  
Think the precision itWorks bearings best choice?

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**Author:** ![nopick](https://avatars.discourse-cdn.com/v4/letter/n/7bcc69/32.png) [@nopick](https://forum.lulzbot.com/u/nopick)\
**Post date:** [December 17, 2019, 4:42am UTC](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670/22 "2019-12-17T04:42:36Z")

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The Mini 2 shipped with RJMP-01-08. Here is the product page for that bearing.

[https://www.igus.com/product/?artnr=RJMP-01-08](https://www.igus.com/product/?artnr=RJMP-01-08)

If you are going to stick with the IGUS plastic bearing, yes, the RJMP is the best choice. The RJM series fits the rod much looser.

RJMP ID- Tolerance +0.000 +0.040 mm  
RJM ID- Tolerance +0.025 +0.061 mm

The BOM for Mini 2 is here: [http://download.lulzbot.com/Mini/2.0.6/production\_docs/](http://download.lulzbot.com/Mini/2.0.6/production_docs/)

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**Author:** ![mrvanes](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.lulzbot.com/mrvanes/32/103_2.png) [@mrvanes](https://forum.lulzbot.com/u/mrvanes)\
**Post date:** [December 17, 2019, 12:30pm UTC](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670/23 "2019-12-17T12:30:03Z")

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I had to replace my carriage with Biolumo’s version to fit the LM8UU ball bearings. I don’t think there are drop-in replacement ball bearings available.

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**Author:** ![nopick](https://avatars.discourse-cdn.com/v4/letter/n/7bcc69/32.png) [@nopick](https://forum.lulzbot.com/u/nopick)\
**Post date:** [December 17, 2019, 1:59pm UTC](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670/24 "2019-12-17T13:59:59Z")

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Comparing the specs of a LM8UU to the RJMP-01-08, the outer diameter is 1mm larger on the RJMP.

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**Author:** ![mhristau](https://sea2.discourse-cdn.com/flex020/user_avatar/forum.lulzbot.com/mhristau/32/9696_2.png) [@mhristau](https://forum.lulzbot.com/u/mhristau)\
**Post date:** [January 31, 2020, 7:34pm UTC](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670/25 "2020-01-31T19:34:41Z")

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Thanks for all the responses.  
So, with a Mini 2 from earliest production run, seems I’m supposed to have the precision bushings. I cleaned the rods thoroughly with alcohol and still had groaning. So, have applied a drop of Tri-Flow and groaning no more.

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**Author:** ![jim2386](https://avatars.discourse-cdn.com/v4/letter/j/6bbea6/32.png) [@jim2386](https://forum.lulzbot.com/u/jim2386)\
**Post date:** [February 3, 2020, 8:44pm UTC](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670/26 "2020-02-03T20:44:45Z")

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I made a step by step video on how to replace the X axis toolhead bearings. Enjoy.

[Previous page](https://forum.lulzbot.com/t/replacing-polymer-bearings-on-the-x-axis-on-the-mini/3670.md?page=1)