Thanks for the replies,
Handleman - yes this exactly what I mean, I've never seen linear rails installed inverted and overhead and thought there was a reason for it. And I guess it doesn't matter where it comes from, but the 20m track length (cut into sections) would be easier to ship if...
I would look at fluid tripod heads, they are concerned with smooth rotational motion
https://youtu.be/jlJ-dRw-DyY?t=470
A layer of grease, delrin disk, or other friction reducing material can be used. If you have the space and budget, angular bearings or tapered roller with a pin/bolt at the...
I am having trouble sourcing a linear rail to be mounted overhead on a ceiling for a precision application with +/-0.1mm repeatability, manually operated at low speed <0.5m/s, 200kg load, track length of 20m. If I use two inverted Hiwin rails in parallel, would that be considered bad practice...