my router build - advice needed

[jonnie]

For Machines like Plasma you'd say Unsupported are fine because there's no Cutting forces involved but Again Plasma can give off very Harsh dust that will Kill the Cheap Bearings in short order so it would be false Economy and more hassle in the long term.!!!

Point taken regards dust from plasma but I would not undertake a plasma build without isolating the rails from dust, not only that I would also isolate myself from dust/fumes since (dependent on metal) these byproducts are not very nice for the lungs or general health either. I would follow advice regards rail choice from more experienced builders but at the same time I would always strive to isolate rails as much as possible from dust of any kind as I dont think that bearings and dust are great bedfellows period - ok metal swarf may simply be pushed along as the vee ways on my old Boxford demonstrate but instinctively I would not trust any linear bearing against the ingress of plasma or wood dust without secondary physical isolation.

Thanks jonnie