Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, Adam Seychell <a_seychell@y...> 
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:)
> > 
> > gr Roel (holland) 
> > 
> > 
> 
> Are you talking a rotating drum laser photoplotter ?
> 
> Any idea of suitable low cost (<$5 A3 sheet) red light 
photosensitive film ?
> 
> There is also the problem of developing red light sensitive films!
> 
> Alternative is green, blue or even UV laser diodes. Choice depends 
on 
> photofilm and laser diode availability. Maybe the best approach is 
to 
> look at traditional black&white photographic films, and then decide 
on 
> suitable laser diode wavelength. Use common B&W films that are 
processed 
> with a standard red safe lights.
> 
> At say 20um wide pixel, that gives 15000 drum revolutions to scan a 
> length of 300mm.  If drum spins at 1000 RPM, thats 15 minutes to 
> complete, which is acceptable.
> Regarding film mounting, it is ideal to have the film placed on the 
> inside of a drum cylinder. The drawback with this approach is 
building 
> single sided bearing mount system for the drum. I guess thats all 
up to 
> degree of mechanical balancing.
> 
> Would be interesting hearing ideas too.
> 
> Adam
>
hi Adam,

Drum type would be nice but controlling and software tooks a great 
deal of time to create i think !
must be somthing like a tv set creating a image on the screen with 
sync goto next line :) lol


gr. Roel