hiya happymacer!
Thanks for the tip on the left hand thread and bearings. I don't see mention being made of torque setting in the manual, just "tighten bolt X" ! A cheap and nasty method I've used on bikes is to dab a permanent marker onto the join of the base metal and the nut *before* loosing (and cleaning of oil with acetone, say) ... and then tightening again until they line up. I've tested this method using a torque wrench on bike axle nuts to 100Nm - it works!
... but yes, one can only torque to spec ... if one knows the spec ... and has the right tool :/
Cool! I'm on the right track with those bearings then
Don't think they cost too much ... but will wait and see.
Here in SA, "WD-Hearn" have been selling the machine for years ... so I won't imagine that spares would be a problem. In fact, I need to get a quote from them for several items anyway so will ask about the spring as a matter of interest.
I intend applying some copper-slip to the tapered sliding plates in the near future, but machine oil had to do in the interim (slightly messy, but effective).
PS. The main reason I wanted the free turning table-screws was to satisfy my curiosity of maybe using stepper motors. I get slightly "increased" resistance for about the last 20mm of travel as the bed nears the column (Y-Axis). No significant increases in resistance on the X-Axis - hence my intention of getting at the sliding plates with the copper slip as well.