Bear 2.1 linear rails addon

thingiverse

These parts are customized versions, highlighting the differences: - Rail_bracket_MGN12C: it's only 2.6mm instead of 3, this to keep bed at the same height as the original Prusa Bear. MGN carriages blocks may be screwed directly to the bed plate. - build_helper_y: The Bear aligns 8 mm rods while rails are 12mm wide. This helper is 2mm shorter. - z_motor_mount considers 13mm as offset not 13.3mm and is ready for 40mm steppers. - x-ends consider 13mm as offset not 13.3mm. - x-ends updated to Bear extruder 1.0.0 (with motor autocenter feature). - x-ends for non-standard POM (22mm). - x-ends with T screws coupler slot (required because of 40mm steppers). **Please note these parts can't be mixed with original ones, you may still change 13mm references to 13.3 into source Fusion files to get compatibility. Note that due to changes from beta version to final BearExxa, the carriage is changed from 10mm to 11mm in thickness, so some differences exist even in that part**. I used 2.0 mk3 frame (at the moment Bear 2.1 is in RC stage), then Z aluminium profiles are tapped and I can reuse rails Z top parts. Since 2.1 top parts don't require tapped profiles, I suspect newer profiles will miss screw thread. 09/07/2020: Minor changes to z_tops and updated sources. 02/07/2020: Change in x-end-idler, added a screw to adjust for rail length compensation (rod one was already present). 26/06/2020: Added x_end_motor_cover_ext. This is required when Z motors couplers are installed. During home fan screw crash into one of them. I lose 4mm on X to prevent this. Also added Z align updated to current Bear 2.1 RC1. 03/06/2020: Added Fusion360 sources. Everyone may change measures (but x-carriage) and have interchangeable parts with remix source project. 23/05/2020: Added x_carriage (BearExxa 1.0.0), new z_top_cap with screws protection (I feel that T-screw are a little bit dangerous left so accessible). 14/05/2020: Added also new x_carriages_back to have protected IR sensor cable path (will follow back x_carriage to use them). 13/05/2020: Removed Z help. Since I move all by 13mm, and not as original development that is 13.3, the correct value is really 93 (as original), but I had to change z motors mount (also because I have 40mm high steppers) and x-ends (also modified for non-standard Prusa POM nuts, mine are 22mm in diameter and for coupler). 13/04/2020: Changed from 2.4mm to 2.6mm. Checked original Fusion 360 Bear sources. Bed is lifted 15.6mm from profile. Since rail is 13mm then 2.6 is right value. Removed carriage block (It comes from original v1 and with original v2 brackets it's no more used). 23/02/2020: Splitted v2 parts and restored thickness for screw. 19/02/2020: Fixed rail holder v2. Part was not touching bed plane (was lifted). 18/02/2020: Added rail holder V2, always 2.4mm instead of 3mm. With this part carriage block isn't required anymore. 10/02/2020: Changes on build_helper_y. Increased area in contact with rail for a better alignment. 26/01/2020: Original helper has been modified and here is new version