The Bear Upgrade replaces the original Prusa i3 MK2(S), MK2.5(S) and MK3(S) frame with a more rigid and reliable solution. It allows faster prints, increases precision, makes maintenance easier and opens the door to more customization. Plus it looks unique with our coloured frames!
Here are the features that explain why I decided to create another printer upgrade.
- Use as much as possible original parts (no need to print a new RAMBo cover nor change any cable, rods or firmware)
- Compatible with MK2, MK2s MK2.5 and MK3
- Let user choose between two versions :
- Half upgrade : similar to MK3 and cheaper
- Full upgrade : stronger but more expensive
- Highly detailed manual
- Use more aluminum and less printed parts (3D printed parts can crack and are less reliable)
- Use Openbuilds hardware :
- Single platform of multitude compatible hardware parts
- V-Slot offers more possibilities for printed parts and customisation than T-Slot
- Open source with powerful community
- Easy to square and build
- Worldwide shipping plus several other shops selling these parts
- Other type of aluminum extrusions can be supported thanks to parametric design (check Fusion 360 files)
- 3D printed parts designed using advanced techniques like selective infill, clean vertical holes, sharp angle...
- Open source by providing STL, STEP and Autodesk Fusion 360 files
We are currently working on reducing the number of versions of the Full Upgrade kit. MK2S, MK2.5, MK2.5S will be merged to MK3 frame. Most of the official distributors are already selling only MK3 frame.
- Use this Y belt adapter: https://www.thingiverse.com/thing:3468567
- You will need a new Y belt because MK3 frame is slightly longer. Will be a good opportunity to refresh your old belt. Here is the reference to use with the belt: GATES LL-2GT RF 6mm Width 2mm Pitch 660mm long. Belt From Prusa store works perfectly as well.
- Use all MK2S/MK2.5(S) parts except Y rod holders and build helper.
- You need to use the 106mm build helper
The Prusa i3 Bear upgrade is proposed in two versions: full or half upgrade.
- Half upgrade : upgrade your MK2/MK2s/MK2.5 frame to MK3 type
- Full upgrade : has a redesigned and stronger Z axis for all MK2 and MK3 printers but is more expensive
Here is a comparison table to help you choose :
| Half Upgrade | Full Upgrade | |
|---|---|---|
| Compatibility | MK2, MK2s and MK2.5 | MK2, MK2s, MK2.5 and MK3 |
| Y axis rigidity | ||
| Z axis rigidity | ||
| Noise level | ||
| Customisation | ||
| Material cost | 💰 | 💰 💰 |
| Number of V-Slots to cut | 6 (4 different lengths) |
7 (4 different lengths) |
| Number of V-Slots to tap | 4 | 0 |
| Can I place the printer inside an enclosure and PSU outside? |
❌ PSU rigidify the Z frame |
✔️ |
| Capability to increase Z axis height? (need customisation) |
❌ | ✔️ |
Half upgrade use the same v-slots and printed part for MK2(s) and MK2.5. However, the full upgrade has 3 different versions, one for MK2(s), one for MK2.5 and another one for MK3. You can discover the difference in the full upgrade page.
Several printed parts are shared between all these versions. This makes easier to move from half to full upgrade, or full upgrade MK2 to full upgrade MK3.
Go to HALF upgrade page or FULL upgrade page.
Checkout the best optional parts for you Bear : Optional Parts
Here are the places were the Bear project is the most active. Do not hesitate to ask if you have a question :
- Facebook group : facebook.com/groups/PrusaBearUpgrade
- Discord server of "The 602 Wasteland" community : discordapp.com/invite/hYUjSnW
- GitHub : github.com/gregsaun
- Thingiverse : thingiverse.com/pekcitron
- Openbuilds community : openbuilds.com/builds/prusa-i3-bear-upgrade-v2.6428
Official distributors are selling a kit with all screws and extrusions ready for the upgrade, you will only need to print latest 3D printed parts.
All distributors are following specifications to ensure you will have a perfectly squared Bear. All distributors are using professional machines dedicated to cut aluminum extrusion (like CNC machines). In case your extrusion is out of specifications, you can get a replacement for free. We have created a dedicated support channel in case customers have more technical questions or need information for a custom build.
-
All3D Makers (US)
all3dmakers.com -
Blackfrog (EU)
blackfrog.pl -
Lecktor (EU)
lecktor.com -
Makerparts.ca (CA)
makerparts.ca -
Ooznest (EU)
ooznest.co.uk -
RatRig (EU)
www.ratrig.com
By purchasing a kit from official distributors you are supporting the development of the Bear project, thank you very much!
You can also purchase parts separately worldwide. Checkout my list of distributors here : Openbuilds stores list
LDO Motors is the manufacturer of the Original Bear upgrade kit for all distributors with the exception of RatRig.
3DFused is helping the Bear development team with linear motion knowledge and will sell custom linear rail kit for the Bear Upgrade.
Grégoire Saunier is the inventor of the Original Bear Upgrade frame and extruder.
Florian Däubler, Josh Jones and Stefan Maue are active developers supporting the work of Grégoire Saunier.
Barry Danks, David Ogles, Florian Däubler, Josh Jones, Nathan Denkin, Orlando from All3DMakers, Termlimit are admins of the Bear community and help with translations.
The Bear project is made possible thanks supporters, you can participate via
patreon.com/gregsaun
paypal.me/gregsaun
You can also send me a tip via Thingiverse if you prefer that way.
Massive thank you in advance ❤️
Thank you to all my Patreon : 3D-Maniac, Albe Gouws, Alberto Vargas, Anders Svendsen, Andre, Andrew Bingham, Apton Ika, Arnaud CHRISTEL, Austin Vojta, Bas Borgignons, Bearpaw93, Bojan Kopanja, Brian Tibbetts, Chris Warkocki, Christopher Lee, Christos Goulas, Corey Dryja, Corrado, Cristian Toma, Daniele Malinconi, Darren Furniss, David Pesce, David Tyra, Dejan Vozlic, Doug Palmer, Edward Wright, Erich Jermann, Espen Fjellvær Olsen, Evgen, flobler, Gareth Brown, Garrett White, Garth Clardy, Greg3D, Grigori Palamartšuk, Hector Gonzalez, Imperial Terrain, Jack Emilsen, Jason Bao, Jason Marcus, Jimmy Lee, Joan Torner Corrons, Joel Nielsen, Joel Weinberg, Jonathan Ryer, Joseph Mizrachi, Joseph Quan, Josh Carter, Joshua Jones, JTa, Keith Beaul, Ken Waters, Kevin Smith, Kim Schauss, Kyle Rothrock, Kyle Shaw, Lewis Cheek, Loïc Dumont, Luke Turner, Matthew Humphrey, Michal Kapusnik, Miguel Castillo, Mike Phelps, Moody Wood Carving, Neofitos Papadopoulos, Nicolas Pottier, Orlando E Moran, Patch Best, Peter Bauer (ColdFusion), Peter Boardman, QcRetro, ra100, RC-CnC, Richard Bateman, robert veline, Ryan Lenny, Ryan Lobbins, SamE0717, Satoshi Takanashi, Scott Rini, Settle, Skyler Weinkauf, sleene, Staffsmith aka Thorben Plath, Stanislav Kljuhhin, Stefan Hilbrich, Stephan Kohls, Stephen Pope, Steven Daglish, Ted Rathkopf, Thom Sturgill, Tom Kogut, Tomáš Vydra, Total Dramatist, Tyler Townes, Warren Schultz
Thank you to David Ogles, Flobler, Jason from LDO Motors, Matthew Humphrey, Nathan Denkin, Orlando from All3DMakers, Saiz, Sleene, Termlimit, Vertigo295 for helping me developing the Bear project.
Thank you to all that have send me a tip on Thingiverse and PayPal.
Thank you to everybody from 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.
Here are a list of sources I used to build this project :
- Prusa : http://www.prusa3d.com
- Prusa 3030 Haribo Edition : https://github.com/PrusaMK2Users/3030_Haribo_Edition
- Openbuilds : https://www.openbuilds.org
- Prusa i3 Solidworks parts from jzkmath : https://github.com/jzkmath/Original-Prusa-i3/
Huge thanks to these projects, without them this project can not exist!