Had a go using motorcalc sheet but does not look right.

[irving2008]

Bob,

Thanks for your kind words.

With big screws running at speed you need to locate the leadscrew axially as well as radially, otherwise there is a lot of force on the motor. Skate bearings are pretty poor axially. You either need a pair of deep-groove bearings or thrust bearings, which are cheaper. The diagram shows a simple bearing block that will hold the skate bearing surrounded by two thrust bearings. The picture shows one of my motor mounts, you can just see the thrust bearing against the cover plate, which on mine is screwed in place though not strictly necessary.

Thrust bearings can be got cheaply from TechnoBots who also have an eBay shop.