Homebrew PCBs

Having dome my induction at FabLab Manchester can I say that even their
fairly high power laser cutter (it does 4mm plastic) won't cut PCB because
the surface is too shiny and the copper conducts the heat away . They make
PCBs either by milling and drilling with a Roland Modello or by cutting glue
backed copped strip. I want to try a milling head in a normal flat bed
plotter.

> -----Original Message-----
> From: Homebrew_PCBs@yahoogroups.com 
> [mailto:Homebrew_PCBs@yahoogroups.com] On Behalf Of DmitriA
> Sent: 14 April 2011 16:09
> To: Homebrew_PCBs@yahoogroups.com; Homebrew_PCBs@yahoogroups.com
> Subject: [Homebrew_PCBs] Re: CD shaped PCB
> 
> 
> Sorry for shotting down an otherwise great idea, but having 
> played with these laser diodes quite a bit, specifically in 
> terms of cutting with the beam 
> <http://elabz.com/category/laser-cutting/>  ,  I would have 
> to say that there is just not enough energy in the beam of a 
> regular, off-the-shelf DVD or even Bluray burner to evaporate 
> paint off a copper-clad  FR (or any other solid material for 
> that matter). Copper transfers heat away from the laser 
> ablation point too well, in fact just about any non-porous 
> material does. That's why most of the stuff you'll see cut 
> with these laser diodes is foam.
> 
> Additionally, as others pointed out, the optics of the drive 
> are designed to be focused at a point in a middle of the CD's 
> thickness and even though the lens do adjust floating on the 
> electromagnetic mount, the adjustment would most likely be 
> not enough to focus on the surface (plus the pain layer 
> thickness) instead.
> 
> 
> But I do like the idea in principal and I am planning on 
> upping the energy quite a bit by installing a 1W laser diode 
> (IR or blue) and trying  paint evaporation again. It may just 
> work on a thinnest (0.7 mil's the thinnest?) PCB I can find...
> 
> 
> --- In Homebrew_PCBs@yahoogroups.com, "Boman33" <boman33@...> wrote:
> >
> > Here is a crazy idea that might just work:
> >
> > A first requirement is being able to cut out a PCB the to look just
> like a
> > CD.  It needs to be accurate and typically a lathe would be used.
> Apply a
> > layer of paint or other protective coating over the copper.
> >
> >
> >
> > Pop it into a CD burner that has the Light Scribe or whatever it is
> called
> > feature to mark CDs.  Take the layout and convert it to a 
> JPG and use
> the
> > marking software to place it on the CD.  Several small SMT PCBs will
> fit on
> > a CD.  "Write" the picture to the "CD" and hopefully it 
> will vaporize
> the
> > paint.  Afterwards etch the boards as usual.
> >
> > If the power is controllable, it might also be used to expose a
> photoresist
> > as an alternative.
> >
> > Bertho
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> 
> 
> 
> [Non-text portions of this message have been removed]
> 
> 
> 
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