I am proud to present my all-in-one solution for rebuilding the X- axis for the Ender 3 (Pro) to a MGN12H Linear rail.
I wanted to get rid of the 2020 extrusion, so i completely engineered new brackets for mounting the rail (300mm) and mounting the original black hot-end backplate.
This design uses the original ender hotend!

Now you will only lose 4mm in the Y direction

I was inspired by the 'Ender 3 Linear rail bracket X' design by Denebreona https://www.thingiverse.com/thing:3698212

But i also loved the belt-tensioner made by Misterguru
https://www.thingiverse.com/thing:3319649.
somehow i cant include the remix source files

Therefore i complety engineered these design into my own solution.

I designed three versions for the X cariage bracket:

• Direct drive with front mounted cable chain (Johnniewhisky's)
• Direct drive without cable chain mount
• Bowden drive

I left a little room on the right side of this X carriage bracket so it would fit my current Hero Me V3 hot end mount.

When you use the front mounted cable chain (like i did on the photo's), i recommend to also print the X_motor cover with cable chain mounts i designed.
Also two versions:

• Without camera mount
• With camera mount base (for 'Articulating camera mount https://www.thingiverse.com/thing:3114849).
  I created a few extra parts for this awesome Pi Camera mount and are inclued in the Thing Files section.
  Also print the cableChain_40mountSide_V2 from Johniewhiskey. but inverted in Cura, so you can mount the Z cable chain to the bottom extrusion.

You will need my version of the X tensioner Main body instead of the original one.
The original steel tensioner will not fit on this design.

For bolting it all done you will need the following new bolts:

New bolts amount description
m3x8 45 angled head 4x mount carriage bracket to MGN12H carriage
m5x12 + locking nut 3x mount original hot-end plate to carriage bracket
m4x12 + nut 2x Left bracket to original black wheel plate
m4x12 + nut 2x Right bracket to original black wheel plate
m3x12 + nut 6x rail to brackets left and right
M4x30 + locking nut 1x Tensioner main body and right bracket to wheel plate

Because now the belt is connected to the carriage on the other side of the rail, you will need to invert the X-axis in your Marlin firmware.

I must say i loved engineering this design in Fusion 360, and would like to know your thoughts about my design.
And feel free to buy me a beer if you also love it :)

Happy printing and post your makes