CR10S X Axis Linear Rail Belt Extender

Upgrading the CR10 to a linear rail on the X Axis causes the existing carriage belt slots to be out of alignment as the Rail pushes the carriage further forwards. This bracket corrects the alignment problem and slips over the existing belt clips on the carriage.

I recommend printing with ABS/ASA/PETG with at least 8 walls /bottom layers as this part will be under tension.

Note: Some Linear rail kits come with modified carriages so you do not need this. However you may have a non standard carriage to fit alternate hot ends like Hemera / Roto that are not part of the kit and you don't want to print an additional bracket to attach to the carriage to convert it or drill new holes into the modified carriage that comes with the kit.

I attach a photo of my custom Hemera Carriage with BL Touch support with the adapter fitted and photos of the stock CR10S Carriage with the replacement carriage (red) that comes with the kit with the longer belt arms holding the slots. If you use the supplied carriage in the kit you wont need this bracket as they have already made the arms longer than the stock CR10 carriage, but this carriage is designed for the stock CR10/S Hot End that wont fit an Hemera/Roto.
 

Also be aware that upgrading to a linear rail on the X Axis will also put the X Axis Stop switch out of alignment and also possibly cause the belt to rub against the stand off pillar extension that supports the X Axis end stop. Some people print adapters that connect to the carriage to hit the End stop that is now further away. I chose replace the stand off pillar's with longer 38mm ones that aligns the end stop perfectly with the new carriage position. I also removed the bottom right stand off pillar completely so it did not rub against the belt when the carrage hit the end stop. 

There are two versions depending on the Carriage people have.
 

v1: Where the belt attachment is already close to the X Axis Bar there is a flat profile extender that does not lift the belt any higher.

v2: Where the belt attachment is 5mm lower than the X Axis Bar this lifts the belt up 5mm to be more parallel with the bottom of the pulley and X Axis Bar. If you don't do this there will be a diagonal slope on the belt between the carriage and the Pulleys.  This slope needs to be removed to prevent backlash and strain on the carriage, belt and motors as it nears the X Axis end stop. As it nears the X Axis End Stop if the belt slope still exists the angle becomes more acute putting more vertical force on the motor, the pulley and the Belt extender.  

v3: A more sturdy version of v2 as I have had a breakage when over-tightening the x axis tension. So I  added more material to the riser bars and made the whole upper more thick to support the riser bar. If I get any more issues I will lengthen the riser bars and add an end cap.