Sorry, I chose this post as the most recent of yours to reply to; I used to dabble in trying various methods of DIY PCB's and I did try the plotter method with a 7440, trying to figure out which Staedler red pen will suffice,(argh!) but I couldn't do double-sided boards without figuring how to register the board in a way for the plotter to do the second side.
Even with a laser, I'm not sure if this an obvious issue or not a concern as you are only doing single-sided work.
For me, I find Sunday coupon pages printed on my old laser printer adequate enough but the real issue that eludes me from quick PCB fabrication is through-plating.
I am intrigued though, why did you stop going with the direct laser method? The pictures you provided were most impressive but perhaps you ran into the same issue with double-sided boards?
--- In Homebrew_PCBs@yahoogroups.com, mlerman@... wrote:
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> I'm interested in the optics, too. If we could produce a spot of .001 inch or so, we could use it to remove paint resist from a pcb, just like a cnc router. Then etch and done. The plotter can be a simple xy - used ones with a resolution of .001 inch seem to be readily available.
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> Mark
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