This video is for a device which enables faceplate assemblies to be balanced to a higher degree than is possible if attempted whilst the faceplate is situated on the lathe's spindle.
Another feature is that it enables workpieces, with clamps etc. , to be fixed and accurately positioned whilst the faceplate is horizontal. This making it very much easier to populate a faceplate compared to carrying out the task whilst on the lathe's spindle, where three, or more, hands are often needed for the task.
The design uses a simple method of producing the equivalent of ball races on which the spindle runs, avoiding the need to purchase large, and expensive, commercial ball races. Viewing the video just to see how these work may be of interest, even if the fixture itself has no place in your workshop.
A full list of my videos made public so far can be found on this page Harold Halls Videos, index