Thread: Custom Quill

Technically you are on the right track, Dave. But this is a needle roller bearing which needs to run on a precision ground spindle which is hardened. THe bearings in your spindle have an inner track which fits on the spindle, this one doesn't. You can buy the ground and hardened inner bush for these but that then looses you a few more millimeters in ID. Going don the hardened spindle track is a no-go for me or most of our home workshop capabilities (except for a few here).
I would pull the spindel apart, note the bearings that are in there and see what their axial load capacity is before going any further. I don;t know how that compares with the needle rollers you found.
You should find that your spindle has a separate thrust bearing (either end - maybe both for turning) to take axial load, so those forces are separated.
Just keep in minf that this machine is not very rigid at all (no solid bed) and the quill is pretty small. Whatever you do will not improve on that. This is not a machine to invest heavily into in terms of effort, money and time. Modifications to make it more useful is one thing, but a complete redesign of the drive and quill would be a waste.
You'd be better off looking for a much more substantial and rigid machine to start with.
Sorry to sound like a 'stick in the mud' but I'm also being practical.