I would look at hacking one of your old plotters. Remove all but the motors and possibly the power supply. If they used stepper motors you are in good shape just get a low cost two channel stepper driver bord off ebay then drive it Mach3 software. Now it will dance to G-Code which is very close to Gerber.
If they were built with servos you need to find a low cost servo driver like the open source UHU servo board.
Or even change the motor out to low cost steppers.
Then mount a laser diode on the pen holder.
Sounds like a fun project.
Craig
--- In Homebrew_PCBs@yahoogroups.com, "Boman33" <boman33@...> wrote:
>
> I currently have, and I have used several other models of HP pen plotters,
> but they are old and all of them were analog and took a varying voltage as
> input. In other words, not easily controlled by a computer without
> additional digital to analog converters.
> Bertho
> ======================================
> From: designer_craig Sent: Saturday, February 05, 2011 14:25
> PC stock would not work in a larger HP plotter, you have a grit roller and a
> rubber pinch roller. It depends on the grit pattern digging into the paper.
> Alos the paper bed is curved. You also need a roller set at the other side
> of the paper or it will not run straight.
> Best bet is to find a smaller 11 x17 flat bed HP pen plotter. They had an
> electrostatic system for holding the paper down and a gantry pen holder
> system.
> Craig
>
> --- In Homebrew_PCBs@yahoogroups.com, Mark Lerman <mlerman@> wrote:
> > Yes, I had heard about the indentation. I assume the indents are on
> > the bottom so that I could mount the pcb on paper or cardboard?? Can
> > a pcb fit mechanically without modification?
> > Mark
> >
> > At 04:19 PM 2/4/2011, you wrote:
> > >Note:
> > >The pen moves in the X plane and the PAPER moves in the Y plane. A PCB is
> > >rigid so you would need to attached to the equivalent of a paper carrier.
> > >
> > >The plotter technology is clever with the grit wheels actually indenting
> the
> > >paper on the first pass so the paper on future passes back and forth
> track
> > >the previous indented markings.
> > >
> > >A long time ago I played around with this idea but I was using a fiber
> optic
> > >cable to keep the laser stationary and the weight down for the pen
> assembly.
> > >Today lasers are much smaller.
> > >Bertho
> > >==============================
> > >
> > >From: Mark Lerman Sent: Friday, February 04, 2011 15:38
> > >At 03:25 PM 2/4/2011, you wrote:
> > >
> > > >--- On Fri, 4/2/11, Mark Lerman <mlerman@> wrote:
> > > > > From: Mark Lerman <mlerman@>
> > >homebrew_PCBs@yahoogroups.com
> > > > > Date: Friday, 4 February, 2011, 18:52
> > > >
> > > > > work. Questions:
> > > > >
> > > > > 1 - How good is a plotter's resolution?
> > > >
> > > >Just a quick answer: the basic resolution of HPGL, the
> > > >HP plotter language that nearly all plotters use, is
> > > >40 steps per mm. So, if you add 40 to a co-ordinate,
> > > >the pen moves by 1mm. Now, I don't know if this is
> > > >the mechanical resolution of the plotter, but it sets
> > > >an upper limit to resolution, at least.
> > >
> > >Thanks - that would be .001 inch (1 mil) per step, more than adequate!
> > >Mark
>