I'm about to make a microwave test PCB for the first time, using tone transfer. The PCB size is about 4"x4" with the bottom layer is served as a ground plane. How do I mask the bottom layer so the copper remained intact during contact with ferric chloride? Vaseline? Masking tape? Huge tip marking pen? Some kind of chemical etching resist? TIA Lanny
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How to mask bottom layer from etching?
2008-06-11 by lnphoenix