<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">Mark <div>I have tried exactly as you suggest </div><div>Paint over copper then laser off and etch </div><div>It is written up in a few places on the web (see below) </div><div><br></div><div>I had some success but resolution was a bit to be desired </div><div>(I couldn’t do smd parts) so was not much of an advantage over std methods </div><div><br></div><div>I found the same with milling pcbs </div><div>Résolution was limited to through hole </div><div><br></div><div>I think Russel’s method with screen printing resist and using the transparency from rs components is most exciting for home prototyping <br><br>Be interested to hear how you get on </div><div><br></div><div><a href="https://www.instructables.com/Custom-PCB-Prototyping-using-a-Laser-Cutter/?amp_page=true">https://www.instructables.com/Custom-PCB-Prototyping-using-a-Laser-Cutter/?amp_page=true</a></div><div><br></div><div><br></div><div>David </div><div><br></div><div><br></div><div><div id="AppleMailSignature" dir="ltr">Sent from my iPhone</div><div dir="ltr"><br>On 7/12/2020, at 10:43, Mark Atherton <<a href="mailto:markaren1@xtra.co.nz">markaren1@xtra.co.nz</a>> wrote:<br><br></div><blockquote type="cite"><div dir="ltr">
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<p>Thanks Andrew,</p><p>The hydrogen peroxide/hydrochloric acid solution looks most interesting; never heard of it before.</p><p>My largest complaint back-in-the-day when using Ferric Chloride was the indelible orange-stain that the spills caused.</p><p>Anyway, I am looking into chemical-milling some thin copper sheet, and you may have solved one of the issues.</p><p>Just wondering about spraying a thin layer of paint on the copper. Removing the 'resist' using a laser cutter, then etching the remaining piece.</p><p>Anyone have any experience with a similar process ??</p><p>-Mark</p><p><br></p><blockquote type="cite">On 07 December 2020 at 09:14 Andrew Errington <<a href="mailto:erringtona@gmail.com">erringtona@gmail.com</a>> wrote: <br> <br><div dir="auto">Ferric chloride is nasty, and becoming increasingly difficult to get.<div dir="auto"><br></div><div dir="auto">Try hydrogen peroxide and hydrochloric acid (or hydrogen peroxide and vinegar). Instructions on the web. I have tried it and it works.</div><div dir="auto"><br></div><div dir="auto">Andrew</div></div><br><div class="ox-66116abc8d-gmail_quote"><div dir="ltr" class="ox-66116abc8d-gmail_attr">On Mon, 7 Dec 2020, 08:56 Marshland Engineering, < <a href="mailto:marshland@marshland.co.nz">marshland@marshland.co.nz</a>> wrote: <br></div><blockquote>Is this Ferric Chloride still available in NZ ? <br> <br> I have some ammonium persulfate but FC works at room temperature which makes <br> it easier. <br> <br> Cheers Wallace <br> <br> <br> _______________________________________________ <br> Chchrobotics mailing list <a href="mailto:Chchrobotics@lists.ourshack.com" target="_blank" rel="noopener">Chchrobotics@lists.ourshack.com</a> <br> <a href="https://lists.ourshack.com/mailman/listinfo/chchrobotics" target="_blank" rel="noopener">https://lists.ourshack.com/mailman/listinfo/chchrobotics</a> <br> Mail Archives: <a href="http://lists.ourshack.com/pipermail/chchrobotics/" target="_blank" rel="noopener">http://lists.ourshack.com/pipermail/chchrobotics/</a> <br> Meetings usually 3rd Monday each month. See <a href="http://kiwibots.org" target="_blank" rel="noopener">http://kiwibots.org</a> for venue, directions and dates. <br> When replying, please edit your Subject line to reflect new subjects.</blockquote></div>_______________________________________________ <br>Chchrobotics mailing list <a href="mailto:Chchrobotics@lists.ourshack.com">Chchrobotics@lists.ourshack.com</a> <br><a href="https://lists.ourshack.com/mailman/listinfo/chchrobotics">https://lists.ourshack.com/mailman/listinfo/chchrobotics</a> <br>Mail Archives: <a href="http://lists.ourshack.com/pipermail/chchrobotics/">http://lists.ourshack.com/pipermail/chchrobotics/</a> <br>Meetings usually 3rd Monday each month. See <a href="http://kiwibots.org">http://kiwibots.org</a> for venue, directions and dates. <br>When replying, please edit your Subject line to reflect new subjects.</blockquote>
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