wanted spindle speed increaser for cnc milling machine

[Clive S]

A friend of mine needs to do some engraving usung his cnc mill. He is looking for something that will offer a 2or3-1 higher speed. His mill can accomodate a bt35, bt40 or int40 toolholders. I seem to remember that someone on here bought or made such a device. Any help in tracking something down would be much appreciated. Thanks, G.

Something like this;- http://www.mycncuk.com/threads/7735-...peed+increaser