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Date: Sat, 24 Mar 2012 15:24:14 -0700
From: Colin D Bennett <colin AT gibibit DOT com>
To: geda-user AT delorie DOT com
Subject: Re: [geda-user] Solder paste/nopaste flag overlapping, and custom
 paste apertures
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On Fri, 23 Mar 2012 19:40:41 -0400
Bob Paddock <bob DOT paddock AT gmail DOT com> wrote:

> 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.

Hi Bob,

That's very interesting.  I have never given thought to balancing
the copper mass near the terminals of a chip component before.
I'll add that to my design workflow checklist and keep it in mind.

Regards,
Colin