--- In
Homebrew_PCBs@yahoogroups.com, Adam Seychell <a_seychell@y...>
wrote:
>
> Richard wrote:
>
>
> > Buy one decent spindle, and be done with the problem
> > forever. But the market is probably too small for anyone
> > to make such a thing; especially if nobody is willing to
> > spend more than $39.
>
> There seems to be the conventional electric die grinders at < US$150,
> and the > $2000 specialized CNC PCB drilling spinals, like those
made by
> Westwind. There is nothing in between. As you say the PCB hobbyist
> market is too small and I guess no one needs a 30000+ RPM electric
die grinder.
Well, I had never heard the term "die grinder" before reading this
thread. A quick google search reveals that inexpensive electric
die grinders run from 19000 to 27000rpm. I just bought a Proxxon
professional grinder IB/E rotary tool for $109, including shipping.
Some die grinders cost less; some cost more. One thing I noticed is
they all weigh more --some weigh twice as much as the Proxxon rotary
tool; some weigh four times as much.
Check out the die grinders here:
http://www.mytoolstore.com/makita/mak08-08.htmlI am guessing the weight would not be a factor if you use some kind of
balanced drill press. But it would be a factor if you plan to use
the tool in your hand.
Another factor is speed control. Do the die grinders have a variable
speed that you set with a rotary control like on the Proxxon? Or is
it all open-loop that runs the motor as fast as possible until it's
loaded?
Another factor is collet sizes. The die grinders seem to have a
single bit diameter; the Proxxon has six different diameters.
Is there an advantage to having speeds exceeding 30000rpm?