--- In
Homebrew_PCBs@yahoogroups.com, "lcdpublishing"
<lcdpublishing@y...> wrote:
> Speed isn't that critical for PCB material - It drills fine at 800
> RPM and at 3500 RPM and at 20,000 RPM. When drilling on my drill
> press, I use around 1500 RPM or so, it's quiet and works well.
Yeah, I didn't know anything about the recommended higher speeds until
I got in here. I've never counted, but I would guess I've done several
thousand holes already, and have been running even below what you're
talking about. I'm usually at the lowest, quietest setting on my
benchtop press which is only 620rpm. I'm a bit careless about it at
times, and will use anything on hand, from HSS to carbide, to diamond
burrs.
My usual bit breakage is also with stupid stuff like repositioning the
boards while the tip is blocked by something. The backers have been
lots of stuff, from melamine up to soft pine, but I'm trying to get in
a habit of keeping new clean, flat backer material (maybe tempered
hardboard).
BTW, I've drilled 'into' my finger with a Dremel on high speed before.
It left a perfectly cylindrical hole about 1/16" dia. by almost as
deep. It was really gross to look at, and didn't bleed (just stung).
-George