I was having issues with my Z axis moving inconsistently, and it was binding causing me to lose build height. So I decided to try something different, and change over to smooth rods for my Z axis. To change the Z axis to smooth rods, you will need the parts below.
4 8mmX500mm smooth rods (if you can get longer it is preferred)
4 LM8LUU Bearings
28 M5X12mm screws for upper and lower mounts
16 M5X10mm screws for the bed mounts
44 M5 T-Nuts (I used the drop in kind)
4 M3X12mm screws
4 M3 Nuts
If you print this, I would love to see it, please post it using the "I Made One" Button.
EDIT: With all the design change requests I have been receiving I decided to share the project. You can download it from here
The bearings are press fit into the bed mounts, so your printer does need to be calibrated.