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Date: Fri, 23 Mar 2012 19:40:41 -0400
Message-ID: <CAPYb0EHNvV7Xp8mP+S1zaQiZZRL-XZP9rrwqiGa4w_XTFxLXOw@mail.gmail.com>
Subject: Re: [geda-user] Solder paste/nopaste flag overlapping, and custom
 paste apertures
From: Bob Paddock <bob DOT paddock AT gmail DOT com>
To: geda-user AT delorie DOT com
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On Fri, Mar 23, 2012 at 6:31 PM, Colin D Bennett <colin AT gibibit DOT com> wrote:
>reduce mid-chip solder balls and tombstoning.

Tomb-Stoning is the result of miss-matched copper on each end.
One end has a temperature rise at a higher rate than the other.
Always try to balance the amount of copper on each pad, and more
importantly connected traces (was the pads proper are usually the same
size), so both ends heat at the same rate.

> I recently read about a patch by Andrew Armenia that allows
> shrinking the paste stencil aperture for selected pads (see [1]
> below).

If you are sending to a contractor they will usually tweak the stencil
to match their equipment profile no mater what you supply,
unless you supply the physical stencil which is unlikely, and even
then they still might do their own.


-- 
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