Re: Calcomp Plotter suitibility for XY

Brad,

I missed the point! you have servo motors in the Calcomp! Do you have
a schematic? It's going to be tougher to isolate to the analog "error"
signal you would need to provide. Looks like sending motion commands
via the serial port WOULD be easier!

Makes me think of the "daisy wheel" printers I have been saving for 15
years. Great servo motor (with funny encoder) and driver parts, if I
could "lift" that hardware out of the printer, I might have something
for a "future" big mill project. In fact, I have a box of similar
motors. I was using them as drive motors for a BIG robot. PWM and
H-bridge drivers anyone? Then again, Gecko drives would be the MODERN
way to drive them.

So much hardware, so little time...

Alan



Alan Marconett KM6VV wrote:

>
> Brad,
>
> The Calcomp plotter must have some fair sized steppers. I suppose one
> could compute the x & y scales, and drive it like an HPGL plotter! Pen
> UP/DN could run a stepper between two preset limits for Z. 15:1 might

be

> s.l.o.w., but OK for starters. Are you intending to drive a Sherline
> mill, or your own xy table?
>
> "Heuver, Brad (B.R.)" wrote:
> >
> > I've recently scrapped out a Calcomp 1043GT plotter. It was

able to

> > be controlled with the joystick prior to scrapping, but always had

pen

> > related errors, and was given away by a local school in an obsolete

computer

> > related giveway. It has servo motors, with optical shaft encoders,

and a

> > relativly nice power supply, and servo control board. There are

multiple

> > ports for remote plotter control, and keyboard connections. The

motors are

> > equipped with a small, fine tooth gear, that drives a much larger

gear in an

> > integrated unit. They appear to have a ratio of at least 1:15 ++.
> > Has anybody used a plotter like this for conversion to a CNC
> > controled X/Y device, drill, O/A cutting torch, minimill... It

looks like

> > with the proper driver modifications it could be controlled directly

from a

> > serial cable, with no other electical hardware needed. I would have

to get

> > it out of fault mode, and able to take direct commands, probably with

HPGL.

> > ?
> > What says the collective wisdom of the group?
> >
> > Brad Heuver