--- In
Homebrew_PCBs@yahoogroups.com, Leon Heller <leon355@...> wrote:
>
> On 06/04/2010 22:46, James wrote:
> >
>
> >
> > I find I get the best results doing a quick jab, using a high speed carbide bit with a drill stand I built out of a little precision slide it works great. Take a moment to line it up carefully and then plunge, a carbide bit turning around 20KRPM plunges through the FR4 board like a hot knife through butter.
>
> High-speed is best with tungsten carbide drills. My drill only does
> 18,000 rpm.
>
> Leon
> --
> Leon Heller
> G1HSM
>
I don't actually know the RPM of my drill, I used a nice Maxon precision DC motor which is rated 11K RPM under load at 24V, and I run it around 32V with very light load, it's nice and smooth and turns fast. Whatever the case, it drills a nice hole with carbide bits, and the only one I've broken since building this is a 0.020" when my finger twitched while I was holding down the PCB.