Prusa I3 MK2.5S / MK3S / MK3S+ Extruder upgrade

A lightweight high-resolution extruder upgrade for the popular Prusa I3 MK3S 3D printers, featuring an optimized design achieved with the help of the community.
 
This upgrade kit is compatible only with the original All Metal V6 hotend that is supplied with each Prusa.
 
Product Main Features
This extruder upgrade kit is for the Prusa i3 MK2.5S / MK3S / MK3S+.

These are its main features:
Adapted to fit Prusa’s new filament sensor;
Includes one Bondtech’s BMG extruder drive train with 3:1 gearing ratio;
Optimized geometry for heat-sink cooling;
Mount for PINDA probe included;
Less moving weight to reduce vibration and ghosting;
Professional SLS 3D printed housing.
 
NOTICE
This Upgrade Kit does not include the Bondtech drive gears. They are included in your Prusa already.
This Upgrade Kit requires an x-carriage kit to be installed.
You can buy the x-carriage for the MK3S from us or you can download the free STLs models and 3D print the x-carriage parts available also for the Prusa i3 MK2.5. Use the “Download STL files” option of our “Firmware & More” menu to reach the download links.
Upgrade Your Extruder
Upgrade your extruder to a Bondtech Mini Geared with higher gear ratio – 3:1 – that allows for extra push force and higher resolution.
Print Faster Or With Higher Quality
Use a lightweight extruder that will allow your 3D printer to print faster or to achieve better surface quality.
Reduce 3D Printing Issues
Decrease the risk of heat creep to avoid clogs and improve filament feeding to avoid slipping and deformation that cause under and over extrusion issues.
For even more effective HotEnd cooling we recommend a fan with high pressure like Sunon’s MF40100V1-1000U-G99 or similar.
Working Temperature Limits
Bear in mind that if you use this upgrade kit inside a closed chamber, it will have the following set of working temperature limits:
Due to the sensor plastic parts made of HT PLA > up to 60°C (90-100°C when parts are annealed);
Due to the stepper motor > up to 80°C.
 
Upgrade kit With Optimized Design
This is the latest generation Bondtech upgrade for the popular Prusa I3 MK3S, with an optimized design achieved with the help of the community.
 
Bondtech Extruder For Prusa i3 MK2.5S & MK3S & MK3S+
This kit contains only the necessary parts to convert your current extruder to our own popular design based upon our BMG (Bondtech Mini Geared) extruder with 3:1 gearing ratio for better precision and resolution together with optimized geometry for the heatsink cooling and professional SLS 3D printed housing.
It is also compatible with the MK2.5S model.
 
Lightweight BMG (Bondtech Mini Geared)
With this version we also lower the moving weight to reduce ghosting and vibrations or to allow increasing the printing speed. 15% of weight saving was achieved.
 
Addressing 3D printing Issues
The enhanced housing design improves cooling and decreases heat creeping issues that all metal hotends have when printing with PLA. This small enhancement will avoid many clogs.

The increased push force will drastically reduce slipping, shredding and deformation of the filament avoiding most of the common filament 3D printing issues that start with under and over extrusion.
 
Updating the Firmware
To use this upgrade in the MK2.5S / MK3S / MK3S+, the E-steps and Z_Max needs to be updated. Check out the latest version of our firmware here.