--- In
Homebrew_PCBs@yahoogroups.com, "ben_englund"
<ben_englund@t...> wrote:
> I am in the process of making a cnc pcb engraver and it seems like
> the hard part is the designing. >
Ben: I have a time with PHOTOS on these home-brew sites! This one
doesn't like photos in the PHOTOS section, rather have them in the
FILES section. I won't go into the thinking, there.
Look in the FILES section for "Homebrew Equipment...", and click on
that. Then look for a file named DSCN0329, and click on that. That
will give you the photo of my PET-controlled PCB-drill/engraver. The
basic chassis is Baltic birch ply, precision cabinet-work. The white
surface is Formica. The quill is a 92W (aircraft instrument) 400 Hz.
3-phase motor in a "servo casing", and I designed a 400 Hz. generator
circuit to power that. Turns "synchronized" 12,000 RPM. So, will
punch up to 0.1" dia. carbide bits merrily into one layer of FR-4 at
a rate of about 1 hole per second, when within, say, 0.1" spacing. A
bit longer per-hole when 1" or more apart, of course! It was an
excellent learning experience, and still works, but PET is dying, so
I will have to convert to PC use, soon! (will use old laptop for
that!)