Z - Axis Linear Rail Installation
Preparations the key for the rails to run correctly, and lubricating the rails is best done prior to installation.
I use Graphite powder and Graphite oil in spray form for this process.
With the bearing block still attached to the rail work graphite powder into the bearings from the underside, then run the block along the rail. It will feel stiff but will ease after a couple of runs along the rail. repeat this process a number of times working more powder into the bearing block. Once done give the bearings a quick squirt of graphite oil, this must be a very light layer do not flood the bearing.
When fitting the Z - Axis Linear Rail I found Using locating brackets keep the rails parallel during installation, plus stop the blocks from falling off the rails.