Cheap 56,000RPM milling upgrade (not a dremel :)

Hi all,

I found this great link while looking around, for about $150 you can
basically get a air-powered mini die grinder and hold it in a collet on your
mill with a special hollow drawbar for the air intake. This way you get
56,000RPM milling for 2/16" (3MM) and smaller end-mills. But you'll need a
beefy compressor... You need 28CFM to run it 100% duty cycle, but I think if
you turned down the pressure you'd just get a little bit lower rate.

http://www.homemetalshopclub.org/news/feb04/feb04.html#mill

For those of you in the UK, I found one for < 100 pounds

http://www.cromwell.co.uk/KBE2702543K?popup=yes

Just Google or Froogle for "micro die grinder".
I remember finding something similar (but bigger) for about $500, which had
an air inlet on the side, and a centrally aligned stub which would fit into
a collet, but this mini-mod seems a lot better/economical for the hobby
CNCist. With a 3mm ballnose cutter you'd be able to cut at a rate of like
1.5M/mm! As it is anyway, I only tend to need the high speeds for small
cutters, this would be ideal for parallel finishing on engravings.

Not affiliated with any of these guys, just seemed a very good idea.
Especially since it's a lot more realistic than trying to make my own pulley
for my desktop mill to try and get 4000RPM out of bearings only rated to
2100.

(Don't forget to wear goggles or, best yet, have a cabinet around your CNC
if you start running your endmills at these high speeds. When they ping,
they automatically home towards your face/eyes/soft tissue.

~Abby