I mostly hacked Jonas KÃ¼hling work, so all the credits go to him
what did I do?
I converted from LM8UU to LM12UU and from M3 screws and nuts to M4.
I also made the whole thing thicker and put a bigger mouthplate with added nut holders.
It helps me greatly to glue the nut in the nut holder and then just turn the screw.
I also added a small end stop for the LM12UU. As I will use those holders to mount my Z axis in my CNC I thought that maybe the added support is worth the extra plastic.
Well these holders have orientation ;)
as you mount 4 of them on each axis supposedely the end stops should look away from the center of the axis
where ---- a rod
::: the holders
and | is where the endstop should be.