I must be missing something.
I have a Benchtop Pro machine with 24" gantry travel and 36" long axis travel. The linear actuator for each axis is just an elongated "Z" axis. Like a dummy, I extensively used my machine without additional lubrication for nearly two years. My gantry axis, which is by far the most heavily used axis, failed and I noted that the linear slides were bone dry. I have a new actuator installed and the machine is operating again. CNCRouterParts told me that I need to use a grease gun with a needle fitting to inject grease into each of the four bearing blocks in each linear actuator every three to six months. I am to "simply" remove the dust covers, and then remove the central screw from the outside end of the dust cover for the bearing block. Then I am apply the grease gun needle fitting and inject 3-4 squirts of grease. Finally, I need to replace replace the screw and reinstall the dust covers for the actuator. OK I was able to do that to both of my long axis linear actuators. Since the gantry actuator is brand new and factory lubricated, I will defer that axis until I lubricate the machine again.
Problem is lubricating the Z axis. It was easy to expose the two top bearings of the Z axis linear acturator, remove the central screw, inject the grease, and the replace the screw. Problem is the bottom two bearing blocks are impossible for me to reach because the bottom two bearing blocks are covered the the mounting extrusion for the spindle. Here's a couple of photos:
How does everyone here reach that screw? Since all the Pro machines have this Z axis, surely someone has figured this out!