I did use the Silver Sharpie and had terrible results. It burned off the PCB and floated just like India ink did. It left streaks of etched hairlines inside 1/8th inch traces. More than once. So...nope... no Silver Sharpie for me. I thought maybe it was an age issue becuase I do use silver sharpies to write on black plastic cases..... so I tried a second time using a brand new fresh silver sharpie... and got floaters. My test method is VERY consistent. The copper PCBs all come from the same source. I scrub until shiny and scratches with very fine sand paper then wash clean with acetone. THEN apply thin ink line for testing. I make one pass with a marker and usually leave just enough pigment to be translucent and then I apply a second coat..... usually then being the dark color its supposed to be. BUT the enamel craft paint went on translucent where thin... dark black where thick (paint brush) and I noticed that even those very thin layers blocked etching.... much better than my silver sharpies ever did. MY etch mixture is 100ml of 3% hydrogen peroxide and 50ml of 30% muriatic acid. My etch time is usually about 6 minutes. It has been extremely consistant results again and again so I am very pleased with this process. My quest for a good etch resist is driven by the fact that the readily available sharpie products failed me.... drying out before I was finished touching up a board.... and then the silver floaters and streaking. The sharpies drying out might be just be because I take much much longer to trace over toner traces than normally done by the rest of you all with good vision. So if I have to resort to a wetter etch resist...like craft paint in a bottle... then I'm OK with that idea. On 12/01/2016 09:05 AM, AncelB mosaicmerc@... [Homebrew_PCBs] wrote: > > Use a Silver sharpie for touch ups or simple circuits. Over the counter > goodness, needing no extras or special skills. > > > ------------------------------------------------------------------------ > Posted by: AncelB <mosaicmerc@...> > ------------------------------------------------------------------------ > <https://groups.yahoo.com/neo/groups/Homebrew_PCBs/conversations/messages/35278;_ylc=X3oDMTJxbG5uMDU0BF9TAzk3MzU5NzE0BGdycElkAzQ1MDUzNjEEZ3Jwc3BJZAMxNzA1MDgzMjkxBG1zZ0lkAzM1Mjc4BHNlYwNmdHIEc2xrA3JwbHkEc3RpbWUDMTQ4MDYwMTE0MA--?act=reply&messageNum=35278> > > > > > > > > >
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HOBBY CRAFT ENAMEL WORKS silver sharpies did not work for me
2016-12-01 by Rob