---------- Forwarded message ----------
From: Marcin Jakubowski <joseph.dolit
...@gmail.com>
Date: Tue, Nov 24, 2009 at 10:36 PM
Subject: [RepLab] Re: Open Source Direct Metal Laser Sintering
To: replab@googlegroups.com
Friends,
Can we source suitable diode lasers of 1 watt for this purpose,
readily off-shelf?
Can you discuss the industry standards? What kind of power and spot
size do they need?
What are the limits to the effectiveness of laser sintering -
primarily access to powders? Are these powders economically feasible
to obtain?
It seems the laser can be done relatively easily. I question the
ability to get the proper quality control on powder at reasonable
cost.
Please shed some light on these issues.
Marcin
On Tue, Nov 24, 2009 at 5:21 PM, Sam Putman <atmanis...@gmail.com> wrote:
> On Tue, Nov 24, 2009 at 1:30 PM, VDX <vdi...@web.de> wrote:
> > Hi Sam,
> > ... thank you for the invitation - i'll read through and will post my
> > experiences here too ...
> > Like mentioned in the linked post i've already made some tests with
> > melting black rock-spheres of uniform size around 100 microns.
> > With my laser 2 Watts DC in a spot of 10 microns diameter was enough
> > to evaporate the spheres and make 'nanospheres' which aren't black any
> > more, but more of a translucent green.
> Nice! Sounds like you have far more power than you need.
> Do you know anything about the fabrication of these tiny rock spheres?
> I know one can produce a finely divided metal powder through
> precipitation, although what to do with the waste eluent can be a
> puzzle.
> > When working with other lasers (e.g. pigtailed diodelasers) you have
> > to calculate the energy-density in the spot - i have another 1Watt-
> > diodelaser with spotsize around 60 microns but much worser coherency.
> > I think for the same efficiency like the Yterbium-fiberlaser at 2
> > Watts i'll need a 60Watts pigtailed diodelaser!
> I know a diode laser is something that takes a clean room to build. Do
> you know anything about building Yterbium fiber lasers? What about
> blown glass for CO2 lasers?
> I know next to nothing about laser heads, and whether it's at all
> pragmatic to think in terms of designing a laser source that can be
> fabricated efficiently on a small scale.
> > When the exhausting is working, i'll make some more experiments with
> > plastic-powders, sand and other materials.
> > For sintering metals i'll need inert gas, what's the next step
> > then ...
> Make sure your exhaust system won't leak oxygen, then:
> Take over the world!
> Or: Make finished metal parts out of powder, with a laser!
> For extra credit, figure out how to make nanometer-scale metal
> particles from scrap.
> cheers,
> -Sam.
--
--------------------------------------------------
Marcin Jakubowski, Ph.D.
Open Source Ecology
http://openfarmtech.org/weblog
http://www.replab.org
marcin at replap dot org
Skype: marcin_ose
--------------------------------------------------
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