Dan...
If you use an Angular Contact bearing you will need a housing for the bearing. If you use a Double Angular Contact Bearing (mostly used) you do not need a Thrust Bearing. Also you need to use a spacer between the bearing and the nut. Have a look at the NSK site at the bearing block arrangements.
Isel have an excellent Rolled Lead Screw 16mm that is ideal for a Z Axis and they sell for less than $100 with the ends already machined.
cheers |