Is this 3D model free to download?

Yes, Prusa MK3s Extruder Carriage for Bear X-axis is free to download from Thingiverse. Open it in the free Thinger app, or use the "Download from Thingiverse" link to open the original listing by the creator.

Where do I download the STL file?

The download is hosted by Thingiverse. Use the "Download from Thingiverse" link on this page to open the original listing and grab the file, or save it to your print queue in the free Thinger app.

Designed by RoboMagus, published on Thingiverse. Please credit the creator when sharing your print.

Can I print this at home?

Yes. This is a printable 3D model intended for home FDM and resin printers. Check the original listing for suggested print settings.

Prusa MK3s Extruder Carriage for Bear X-axis 3D printable model by RoboMagus

Prusa MK3s Extruder Carriage for Bear X-axis photo 1

Prusa MK3s Extruder Carriage for Bear X-axis photo 2

Prusa MK3s Extruder Carriage for Bear X-axis photo 3

Prusa MK3s Extruder Carriage for Bear X-axis photo 4

Prusa MK3s Extruder Carriage for Bear X-axis

Source: Thingiverse by RoboMagus

The Prusa MK3s Extruder Carriage for Bear X-axis is a free printable 3D model from Thingiverse by RoboMagus. This is a modification of the original R4 extruder carriage for Prusa MK3s / MK2.5s to make it compatible with pekcitron's Bear X-axis, as the MK3s STILL does not offer a decent. You can download the STL file from the original listing below and print it at home.

Open in Thinger (free) Download from Thingiverse

86 saves Source: Thingiverse Updated 2026-10-16 License: CC-BY · commercial OK 1 makes Category: 3D Printer

Tags: bear, carriage, extruder, mk3s, MK3 R4, Prusa mk3s

About this model

This is a modification of the original R4 extruder carriage for Prusa MK3s / MK2.5s to make it compatible with pekcitron's Bear X-axis, as the MK3s STILL does not offer a decent X-axis belt tensioning mechanism. The original Prusa carriage was modified in Solidworks based on the sources by jzkmath. The belt path is modified to match that of the Bear Extruder but is otherwise completely compatible with the MK3s extruder. The belt chanel was tightened w.r.t. the original prusa model to prevent the belt from slipping. In addition the belt channel is extended beyond their default length to accomodate longer belts without the need for trimming them. The back part of the carriage was also modified in order to maintain belt access in its relocated position. Update [17/4/19]: My MK3s updgrade part…

Frequently asked questions

Is this 3D model free to download?: Yes. Prusa MK3s Extruder Carriage for Bear X-axis is free to download from Thingiverse. Open it in the free Thinger app, or use the "Download from Thingiverse" link above to open the original listing.
Where is the STL hosted?: The download is hosted by Thingiverse, not by Thinger. We link you directly to the original listing by RoboMagus.
Who made this model?: Designed by RoboMagus, published on Thingiverse. Please credit the creator when sharing your print online.
Can I print this at home?: Yes. This model is intended for home FDM and resin 3D printers. Check the original listing for suggested print settings like layer height and supports.