Centauri Carbon double shear motor mounts

What does this mod bring you?

• Higher gantry stiffness even with same belt tension due to stepper shafts being constrained

• Possibility to tension the belts to spec (need to shorten the belt by ~3 teeth to reach full tension))

• no risk of breaking stepper motor shaft

• Allows for a lot less ringing due to higher belt tension

• Reduced noise from X axis bearing rattle

Prerequisites

• Toothed idlers for the X gantry to avoid damaging the belt 

• New nema17 motors or access to a grinder to D the shaft and remove the pulley, I used 

Supports stepper shafts up to 31mm, with an absolute minimum of 20mm (not recommended)

BOM

* Affiliate link from SilencedFrost

Print settings

• Print as oriented

• no supports

• 5 walls

• 30% TPMS-D infill

• 2 infill multiline

• ASA/ABS at least since the motors get hot and it's under a lot of tension
  (absolutely avoid PLA and PETG)

• If you anneal it, make sure to install the heatset inserts beforehand

Installation

It's very complicated and convoluted. Follow this guide and it will show you how to access the motor brackets: https://wiki.elegoo.com/Centauri-carbon/how-to-replace-the-x-axis-and-y-axis-linear-bearings

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V2 - 24/05/2026 Widened idler mounting to use runice idlers.

V2.1 - 26/08/2026 Adjusted pin pushout holes to be easier to use