PCB Routing - Dremel

Hi;

I recall seeing some threads regarding the choice of Dremel drill
for PCB routing, something about one (or more) of the models has
thrust bearing which would prolong it's life if you use it as a high
speed Router Spindle on a Sherline Mill - any ideas ???

Didn't someone design a adaptor to attach a dremel to the sherline Z
axis ??

Any help greatfully appreciated.

CrankShaft.