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Date: Mon, 5 Feb 2024 12:01:11 +0100
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Subject: Re: [geda-user] Solder mask commands?
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I submitted the modified board, and all is well now -- but I still got 
into a bit of a discussion about this solder mask oversize/expansion thing.

I remarked that this was the first time in many decades that I was asked 
to set the solder mask oversize to zero, however the person from the PCB 
house said that zero oversize has been the industry standard for at 
least 20 years, ever since the lithographic workflow wasn't exclusively 
based on photographic films any more. But when I look up best design 
practices for various PCB design packages and other sources, I still see 
a small (usually 4 mil) expansion size mentioned.

So what is it? Would it be a good idea to henceforth use zero oversize 
solder masks? What do people around here do?

Thanks for any thoughts.

Richard