I'm currently shopping for ballscrews and supports for my CNC lathe project (which will come shortly after I finish wiring my mill) and I have the opportunity to buy some modular NSK ball screw supports, model WBK35DFF-31.
These are heavy units made for 35mm precision rolled ballscrews, and each unit has 4 of these bearings:
http://www.consbrgs.com/details/108/108_1_16.html
already mounted and preloaded inside. It almost seems like the bearings would be worth the price ($50 a piece).
What I'm wondering is if I should get a couple of these, which are oversize for my use, and either get ball screws to match or put a bushing on the screw end to make them fit? These would surely be more accurate and solid than any support I could make myself, if a bit large and clunky for my use.
Alternatively I could buy one of them and use the bearing pairs for making my own supports (or something else, they're nice bearings) although I'd have trouble establishing the preload they seem to need.
Suggestions?
Erik