This is an aluminum frame conversion for the Prusa i3 MK2, MK2s, MK2.5 and MK3.
Josef PRŮŠA has created numerous of incredible 3D printers and its latest Prusa i3 MK3 is capable of very impressive print quality for a very low price. A huge thanks to him and all its team!
One of the down point of the Prusa i3 MK2 and MK3 is the rigidity of the frame. A very good project has solved those problems by using 3030 extrusion aluminum : Prusa 3030 Haribo Edition. So why another conversion build? Check the next section ;)
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
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.
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 -
Makerparts.ca (CA)
makerparts.ca -
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
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
Checkout the best optional parts for you Bear : Optional Parts
Thank you to everybody from Facebook group and The 602 Wasteland community.
Thank you to all my Patreon : Arnaud Christel, Barry from RC-CnC, Darren Furniss, Malo87, Mark Leino, Matthew Humphrey, Orlando from all3dmakers, Sleene, Steven Daglish, Vishesh from 3Dprintonics.
Thank you to all my tippers on Thingiverse : Lucullus, NatDenkin, FurniBird, kabar03.
Thank you for having purchased a kit from an official distributor.
Thank you Openbuilds for your hardware, community and state of mind.
Thank you to people that have helped me in the early days of the project : DoItWithSmile (jay3D), kabar03, xequtor and fishmsk, karlosek.
Thank you for all your comments and issues on GitHub and Thingiverse.
Thank you to Nathan Denkin for improving my english (I know it is not an easy task!) and for building a better assembly guide.
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!