Bear Frame Upgrade 2.1

Table of contents

1. Introduction
2. Features
3. New features since Bear Frame 2.0
4. Compatibility
5. Printed parts
6. Print settings
7. Assembly guide
8. Bill of materials
9. Optional parts
10. Community
11. Where can I get an official kit?
12. Partners and contributors
13. Support my work
14. Thank you
15. License
16. Credit, sources and inspiration

Introduction

The Bear Frame Upgrade improves stiffness and reliability of the original Prusa i3 MK2(S), MK2.5(S) and MK3(S). It allows faster prints, increases precision, makes maintenance easier and opens the door to more customisations. Plus it looks unique with our coloured frames!

Features

• Compatible with Original Prusa i3 MK2(S), MK2.5(S) and MK3(S)
• Compatible with lots of extruders like Original Prusa, BearExxa, BearMera (E3D Hemera) and Bondtech Prusa Upgrade
• Reuse of as many parts as possible
• Sturdy frame for faster printing
• High quality extrusions
• Custom, sturdier t-nuts
• Improved accuracy
• Reduced noise level
• Easy to use and maintain
• Built to last
• Precisely engineered printed parts
• Thoroughly tested development
• Highly customisable
• Detailed documentation via guides.bear-lab.com
• Active and open minded community
• Truly open source

New features since Bear Frame 2.0

• Improved assembly guide and documentation (via guides.bear-lab.com)
• Single frame for all Prusa versions (same frame as Full Bear 2.0 MK3)
• New stiffer Y axis with tensioner
• New stiffer Z axis
• Improved X and Y axis homing accuracy
• Improved Z axis alignment and assembly
• Reduced Y axis stepper noise for MK3(S)
• New build helpers for Y and Z axis
• Support for all Prusa PSUs
• Custom, sturdier t-nuts
• Shorter LCD supports
• New custom LCD cover
• Nicer and more resistant end caps
• Easier assembly of printed parts
• Improved wire management with new cable clips
• Stiffer mounts for Rambo Mini/Einsy cover
• Compatible with E3D Gates idlers as well as 9mm belt

Compatibility

This Bear Frame Upgrade 2.1 is compatible with the Full Bear Frame Upgrade 2.0 MK3 frame. If you do not know which frame you have please check our FAQ here.

💡 If you have a Full Bear Frame Upgrade 2.0 MK2S or MK2.5 frame you can find compatible parts in the optional parts section below.

⚠️ The new Y and Z axis are not compatible with any of the existing Prusa or Bear 2.0 parts. You have to update all parts from Bear 2.1.

Printed parts

💡 All links here correspond to the latest stable release.

⚠️ Warning: It is important to follow the recommended print settings and to calibrate your extrusion multiplier before printing the parts (for each and every spool that you use). Check our calibration guide here.

Printed parts:

• Bear Frame 2.1 for MK3(S) STL files: bear21_mk3-3s_stl.zip
• Bear Frame 2.1 for MK2(S) or MK2.5(S) STL files: bear21_mk2-2s-25-25s_stl.zip
• Bear Frame 2.1 optional parts (check optional parts section below) files: bear21_optional_parts.zip

CAD, drawings and source files:

• Bear 2.1 frame for MK3(S) CAD files and mechanical drawings: bear21_cad_drawings_files.zip
• All source files (this complete repository): Go the to latest release here and in the bottom of the release note, under the Assets, click on "Source code" (you can choose between zip and tar.gz files).

Print settings

⚠️ Warning: It is important to follow the recommended print settings and to calibrate your extrusion multiplier before printing the parts (for each and every spool that you use). Check our calibration guide here.

Read the print settings here.

Assembly guide

Read the assembly guide here.

Bill of materials

Read the BOM here.

Optional parts

Official optional parts

Community's optional parts

Find optional parts designed by the community at guides.bear-lab.com/Wiki/community_optional_parts.

Community

Here are the places were The Bear project is the most active on:

• Discord server of "The 602 Wasteland" community : discordapp.com/invite/hYUjSnW
• Facebook group : facebook.com/groups/PrusaBearUpgrade
• Twitter : @gregoiresaunier
• GitHub : github.com/gregsaun

Do not hesitate to ask if you have a question.

Where can I get an official kit?

Official distributors are selling a kit with all screws and extrusions ready for the upgrade from an Original Prusa, you will only need to print 3D printed parts.

• 
  All3D Makers (US)
  all3dmakers.com

• 
  Blackfrog (EU)
  blackfrog.pl

• 
  Lecktor (EU)
  lecktor.com

• 
  Makerparts.ca (CA)
  makerparts.ca

• 
  Ooznest (EU)
  ooznest.co.uk

By purchasing a kit from official distributors you are supporting the development of the Bear project, thank you very much!

Partners and contributors

 LDO Motors is the manufacturer of the official Bear frame upgrade kit for all distributors.

 3DFused is helping the Bear development team with linear motion knowledge and will sell custom linear rail kit for the Bear Frame Upgrade.

Grégoire Saunier is the original designer of the Bear Frame Upgrade and Extruder.

Bendix Sørensen, David Ogles, Florian Däubler, Josh Jones and Stefan Maue are active contributors.

Barry Danks, David Ogles, Florian Däubler, Josh Jones, Nathan Denkin, Orlando from All3DMakers and Termlimit are admins of the Bear community and help with documentation.

Support my work

The bear project is made possible thanks to its supporters. You can participate via


patreon.com/gregsaun


paypal.me/gregsaun

You can also send me a tip via Thingiverse if you prefer.

Massive thank you in advance ❤️

Thank you

Massive thank you to Adrian Bowyer for having invented RepRap.

Thank you to all my Patreon's

Thank you to Bendix Sørensen, David Ogles, Florian Däubler, Jason from LDO Motors, Nathan Denkin, Orlando from All3DMakers, Sleene, Termlimit, Josh Jones and Stefan Maue for helping me in developing the Bear project and for their beautiful support to the community.

Thank you to all that have sent me a tip on Thingiverse and PayPal.

Thank you to everybody from our Facebook group and The 602 Wasteland community.

Thank you for having purchased a kit from an official distributor.

Thank you to all official distributors for taking care of the kits and customers.

Thank you Jason from LDO Motors for the quality manufacturing and relationship.

Thank you Openbuilds^® for your hardware, community and state of mind.

Thank you for making the community alive with all your comments, issues, pull requests, optional parts, make, pictures, etc.

License

All files in this repository are licensed under the GPLv3 license (unless otherwise noted). Here is a quick summary; for more details please check the LICENSE file.

What you can do:

• Modify
• Distribute
• Private, commercial and patent use

What you must do:

• Include copyright notice
• Include a copy of the license
• Share source files
• Use the same license (GPLv3)
• Document changes applied

Note: STL and STEP files are generally not source files. The source files are those you use to design your project such as CAD files (Fusion 360), mechanical drawings, code, documentation, etc. However, STL and STEP files are a commonly used format with great interoperability. Therefore, we encourage to share the STL and STEP files in addition to the source files.

Credit, sources and inspiration

• Adrian Bowyer for having invented RepRap.
• Original Prusa i3 printers: prusa3d.com.
• Prusa 3030 Haribo Edition: github.com/PrusaMK2Users/3030_Haribo_Edition.
• Openbuilds^® for the invention of open source V-Slot^® extrusions : openbuilds.org.
• Roy Henriksson for the inspiration of his Y axis tensioner : thingiverse.com/thing:3502543.
• Vecko Kojchevski for his Z axis parts and feedback : thingiverse.com/vekoj/designs.

Massive thanks to these projects, without them the Bear could not exist!