Grégoire Saunier
patreon
Note on the new Bear extruder release
🕑 Added 2019-06-17 09:34:03 +0000 UTC
Hi everyone, we are really close to release the new extruder, we are reviewing and adjusting some links and doc. But there is an important point I want to share before.
The new original Prusa extruder has the hotend placed higher up on the X carriage, it creates a 7mm longer Z axis. Unfortunately, this new feature makes the air around heatbreak and heatblock warmer and it could lead to the following issues:
- It could melt the bottom of the extruder body.
- It will reduce the efficiency of the heatbreak which could create several issues: clog, heatcreep, inconsistency and longer retraction.
- It could make the part cooling less efficient.
- It makes the bottom of the X carriage more fragile. This might need a complete re-design of the X carriage back that would not allow anymore to be split in two parts. Which means you will have to disconnect all cables from the Rambo Mini/Einsy every time you want to change something on the extruder.
- The bottom bearing of the X carriage on the stock extruder could wear quicker.
- Some people are experiencing damaged hotend cables due to the screw of the heated bed cable cover (they have provided a fix to this recently).
To provide an efficient solution to those potential issues we have decided to keep the old position of the extruder on the X carriage. Unfortunately, the original MK2.5S/MK3S firmware is testing the length of Z axis during (XY)Z calibration and selftest so they will fail with the Bear extruder. To solve this we have created a special firmware that will be used ONLY for (XY)Z calibration and selftest. The assembly instructions will guide you easily through these steps to make sure you have a flawless experience with our extruder.
I would be very happy to hear your honest feedback about this approach.
