>Something that since I have extensive experience with, and the destruction >one can cause trying to dispose of spent ferric chloride, I do NOT want to >be involved with ever again.
The guys here etch PCBs with a mix of muriatic acid and hydrogen peroxide, which is much easier to deal with. Google "muriatic acid pcb etching" for more info-- our version is here: http://milwaukeemakerspace.org/2012/04/pcb-with-lasered-paint-resist-and-fast-sponge-etching/ Note that we're using 30% H2O2 rather than the 2% you typically find at a pharmacy (I don't know where they buy it). Supposedly you can "regenerate" the acid mix by bubbling air through it, but we've never gotten that to work, so we just mix up a new batch each time. Instead of photo resist, we use black spray paint, and etch the paint away with a laser cutter. We've tried cutting circuit boards with a CNC engraving machine, with varying results. The main problem seems to be keeping the board absolutely flat-- it tends to warp, and then you don't get a consistent depth of cut. There is a method of "height mapping" the board ahead of time, and using the computer to compensate while engraving. I don't know the details, but it does seem to work. I think it's a plug-in for Mach3. Very careful mounting might also work. ------------------------------------------------------------------------------ Sponsored by Intel(R) XDK Develop, test and display web and hybrid apps with a single code base. Download it for free now! http://pubads.g.doubleclick.net/gampad/clk?id=111408631&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
