I guess if i do fit the servo, adding the enc module is a no-brainer really, daft not to fit it.

The bearings are sealed and hidden completely in this motor, i could likely get some WD40 in there but no grease. My main issues with fitting it are that it will fail some time, probably when i need it, and will then need my cabinet pulled apart to change from VFD to serve drive etc.

It sort of becomes a "might as well fix it now" option i think, then i can benefit immediately from the improved speed control etc. If i sell my tapping heads they would likely fetch enough to pay for the servo drive anyway :)