Hi,
im building a small CNC type machine using steppers and belts to move
a dremel in 3 axis, controlled from parallel port. I will use eagle
pcb and then create a gcode file for mach3 to route the isolation.
for moving a laser diode around you will not need any torque at all,
so it would be possible to get away with using a few small stepper
motors from printers or using the assembly from flatbed scanners to
perform x and y movement. but it will be very slow.
if you google up 'orbit picstep' you will find a very nice stepper
driver that has step, direction & enable signals.
I know of UV sensitive boards, where can i get the red sensitive ones
as mentioned before?
-Michael
--- In
Homebrew_PCBs@yahoogroups.com, "roel_cnc" <atmelletje@...>
wrote:
>
> --- In Homebrew_PCBs@yahoogroups.com, "Andrew" <andrewm1973@>
> wrote:
> >
> > >> Roel CNC wrote:
> > >>
> > >> i like the idea of making me own laserplotter.
> > >> tested: a pointerlaser (some cheap thing)
> > >> with an extra focus lense, a red sensible
> > >> film gave me super fine lines (close to a
> > >> single cloth fiber).
> > >>
> > >> did any of us fouling around with this idea !!
> > >>
> > >> tips and suggestions always welcome:)
> > >>
> >
> > > Roel also wrote:
> > > Hi all,
> > > M i started this toppic - got lots of replys
> > > on it with ideas :)
> > >
> > > i gonna use Cunningfellow's pll thing some
> > > stepper for the laser and a dma-16 card -
> > > high speed dio card up to 250kB/s some code
> > > compiled (TPascal)that eats the the 274 (gerber)
> > > files and output to the drum
> >
> > Roel - I have done a bit more work on the PLL
> > thing. That one posted so far was just a test of
> > concept / prototype. There are a few things
> > un-needed and a few other things that are needed.
> >
> lots of schematics on the net for pll that can be used i think
>
> > It was built to do some tinkering with a
> > commercial DC servo motor I had lying around.
> > I finally want to just use a DC brushed motor
> > with some optos ripped out of mice (to make it
> > easier for others to get parts to build)
> >
> > Also - I was planning on getting the data out of
> > a USB port (via an FT232) instead of some custom
> > hardware in the PC (again ease to duplicate).
> >
> > The FT232 can do 4 Mb (which is same ballpark to
> > 250 KB). However if you compress the 1000dpi
> > data even with a simple algo like G3 fax you can
> > fit the data stream down 100 kilo baud (assuming
> > 1000dpi and 10" x 10" board in 10 minutes)
> >
> > I have sourced some toothed belts and linear
> > shafts for moving the laser head. I have also
> > found a source of cheapish lasers that can be
> > focused down to small enough dot size if I can't
> > find a simple repeatable solution for people to
> > do the same with a cheap laser pointer.
>
> i was thinking to use a ldiode from a dvd burner they
> can trow up to 70mw and with a good lense a super ultra thin line
> >
> > Very interested in your thoughts on the carraige
> > part. You seem to have a lot more experience
> > than I with CNC things (and PVC etch tanks).
>
> > Do you think at 1000 (or 2000) DPI that there will
> > be a sticktion problem? Do you think the tooth
> > belt idea is going to be good enough or do you
> > think that I might need to use a very fine pitch
> > leadscrew?
>
> a lead screw for this job will be expensive i think
> first touhts was to use a beld but after some thinking
> a steel wire is super stiff and easy to gear
> >
> > I have done some software on the PC to read a
> > BMP file compress it and send it out to my
> > hardware. I was just going to use and external
> > gerber to BMP thing. However - I have no
> > objections to reading geber directly if you would
> > like to work together on the project.
> >
>
> > The only other though I had from the PC side
> > was to maybe write a GDI driver. That might be
> > a bit out of my league though.
> >
> > andrewm (or cunningfellow to some)
> >
> email me if you like Andrew or maybe msn its faster hey'
>
> gr Roel
>