Re: Stereolithograpy revisited

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "turyga1963" <TIntruder@...>
wrote:

>
> In order to drill a hole in the right place, it has to sync
> perfectly with the correct laser pulse and be absolutely steady when
> it does.

no one mentioned drilling holes.

> If you plan on using galvos effectively, you also better plan on
> buying a really big and heavy granite optical bench to mount
> everything on and provide rigidity for the entire system, galvo,
> motion, and beam path.

Most commercial laser cutting systems (see synrad.com etc) using
galvos have nothing like that.

> Hmmmm...better budget for environmental control system that keeps
> the temperature +/- 2 degrees too.

Laser marking systems are commonly used on the shop floor.

I agree with your overall point but as commercial STL machines are not
operated in refrigerated rooms and do not have granite bases I am not
sure where you are getting this from. Perhaps micro via drilling needs
this, STL I doubt.

Graham

>
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@> wrote:
> >
> > Graham Stabler wrote:
> >
> > >--- In CAD_CAM_EDM_DRO@yahoogroups.com, juan gelt <juangelt@>
> wrote:
> > >
> > >
> > >>has everybody had a chance to expound on his opinions?
> > >>very well, now here are some facts:
> >
> >>http://www.technology.niagarac.on.ca/people/mcsele/lasers/index.htm
> l
> > >>
> > >>
> > >>
> > >>
> > >
> > >Firstly your assumption is that just because you can make a UV
> laser
> > >it must be suitable for stereo lithography but I doubt you have
> any
> > >idea if that is the case or not. I don't.
> > >
> > >
> > >
> > Yeah, the Nitrogen transmission line laser is usually run at 1 -
> 10 Hz
> > rep rate.
> > It would be pretty hard to do any real assembly with only 10
> pulses per
> > second.
> >
> > >What I should of said was we can't afford galvos anyway, my real
> point
> > >being there is not much point worrying about issues pertaining to
> > >technologies that are out of our reach (practically). I was
> refering
> > >to the post directly before mine only.
> > >
> > >
> > >
> > Actually, galvanometer-mirror drivers can be found on the surplus
> market
> > (they
> > used to use them in direct-writing oscillographs 50 years ago) and
> they
> > wouldn't
> > be that hard to make, either. I have some little ones, basically
> two
> > wires suspended
> > in a magnetic field, with a tiny mirror glued in the middle of the
> wires.
> >
> > Jon
> >
>