Re: [CAD_CAM_EDM_DRO] Re: Stereolithography machine

Hi Alan

I don't know what wavelength UV is required for stereolitho, but there is
one 337nm UV laser that is very easy to build. That is a nitrogen laser.
It is even possible to get the nitrogen in air to lase at atmospheric
pressure without a resonant cavity. Not real efficient that way, but it
will work.

I picked up an excimer laser, which normally operates in the UV using some
rreally nasty gas mixes, for cheap just thinking to part it out. It looked
so nice and complete I decided to try it out just using nitrogen--well I
guess the optics were close enough etc and it works very well. It puts out
nice strong pulses of UV, capable of causing bright flourescence on white
paper at some distance. I have no way to measure the actual power output.
Optics should be easier to find than for a CO2 laser.

I don't know if this would even be applicable, but up to now it's been just
a novelty with no application I could see.

Bob

----- Original Message -----
From: "Alan Marconett" <KM6VV@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Saturday, March 25, 2006 5:59 PM
Subject: Re: [CAD_CAM_EDM_DRO] Re: Stereolithography machine


> Hi Skull (?),
>
> I think we need the UV laser stuff first. The XY is easy enough.
>
> They appear to simply do a simple raster scan, so we need to convert
> "drawing" data to a simple raster format. BMP? There is software out
> there to do that.
>
> Then the STL controller would read the BMP file and output a line at a
> time The UV laser needs to be turned on/off in response to each bit in
> the scan line (starting to sound like Jon's photo plotter).
>
> Do a line in say X, then bump up a line in Y, and come back in X. After
> every complete "frame", we'd move a little in Z. Similar to way one
> scans with a digitizing probe.
>
> Any ideas on how to build a low cost focused UV laser?
>
> And it sounds like we then flood the work area with fresh epoxy. A
> little PERISTALTIC pump (the company I work for MAKES them) can do this
> job. Sounds messy!
>
> REMEMBER, we were just dreaming about home CNC a few years ago!
>
> Alan KM6VV
>
>
> skullworks wrote:
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Mat" <bergson7@...> wrote:
> >
> >>Hello friends
> >>I am trying build small stereolithography machine and we have
> >
> > problem
> >
> >>with Ultra violet laser for it. There are a couple sources for it
> >
> > but at
> >
> >>the moment all of them are quite expensive. I am still searching.
> >>
> >>
> >>Is there anybody who made or tried make this in the past ?
> >>Best regards.
> >>Mat
> >>
> >
> > I have never seen any home built STL machines, this may be because it
> > would need its own very unique driver/interpreter - I don't think
> > that anything like EMC or Mach could come close to driving that type
> > of system - unless a very special "repost" would convert STL into the
> > slice segments needed.
> >
> > But - if a set of drawings and an open source type project were to
> > ever surface...it would jump to the top of my TODO project list.
> >
> > I'm going to WESTEC on tues and will drewl over the
> > STL and other rapid prototype equipment, for now its just another
> > technology I can only dream about (and contract out).
> >
> >
>
>
>
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