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From: "karl AT aspodata DOT se [via geda-user AT delorie DOT com]" <geda-user AT delorie DOT com>
To: geda-user AT delorie DOT com
Subject: Re: [geda-user] Solder mask commands?
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Comments: In-reply-to "Richard Rasker (rasker AT linetec DOT nl) [via geda-user AT delorie DOT com]" <geda-user AT delorie DOT com>
   message dated "Mon, 05 Feb 2024 12:01:11 +0100."
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Date: Mon,  5 Feb 2024 12:40:46 +0100 (CET)
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Precedence: bulk

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

One way to see what people do is to look att public footprints (also 
called land patterns), manufacture recommondations, what IPC publishes
and what people writes in blogs.

Now, the question is wheter the designer or the manuf. should do the
sizing, I wote the designer with the manuf. possible fine tuning or
informing the designer of bad choises.
 Perhaps your manuf. have had bad experience with bad designers.

Examples:
 Public footprints
  cvs.gedasymbols.org

 manuf.
  https://www.nxp.com/docs/en/application-note/AN1902.pdf 
  4.2.1.2 Solder mask guidelines for perimeter lands (page 13/50)

 IPC
  https://shop.ipc.org/ipc-hdbk-840/ipc-hdbk-840-handbook/Revision-0/english

 blogs
  https://www.protoexpress.com/blog/what-is-solder-mask-layer/

Regards,
/Karl Hammar