Bearing Material

Hi List,

I am in the throws of designing and building a CNC router/PCB driller and an
not sure as to what material to use as a bearing/guide material. The loading
is quite small but it should locate along a square section aluminium guide
rail. I am looking for a material that can be machined, is available from a
local engineering material suppliers and is also hard and shiny like
Bakelite and will not wear when used against Aluminium. I thought of using
Nylon but I think this would be a little soft.

Terry