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Message-ID:	<4FC6FDFA.1020001@innocent.com>
Date:	Thu, 31 May 2012 01:13:30 -0400
From:	Gus Fantanas <fantanas AT innocent DOT com>
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To:	geda-user AT delorie DOT com
Subject:	[geda-user] Odd Behavior Around Vias
Reply-To:	geda-user AT delorie DOT com

I am using the gEDA package from the repos of Ubuntu 12.04LTS.  I 
finished a layout in PCB, but afterward I had to increase the total pad 
diameter around some vias at the request of the fab house.  After I did 
that FROM THE COMMAND WINDOW, the clearance of two vias (which just had 
the pad size increased) from the ground plane SHRANK to accommodate the 
increased pad diameters.  The ground plane on that board was connected 
polygons to minimize parasitic capacitances at a couple of spots; the 
ground plane was at considerable distance from each of the two vias, 
except in one direction.  After increasing their pad diameter, the 
clearance region of each via should have "eaten into" the ground plane, 
but that did not happen.

It was as if increasing the pad diameter (from the command window) 
"cheated" the via clearance check.  However, after pressing S on each of 
those two vias (to increase the size of their pads further) the 
clearance check from the ground plane "woke up."  Pressing CTRL-S on 
each via to reverse the previous increase MAINTAINED PROPER CLEARANCE!

Therefore, the end result of pressing S and then CTRL-S on each of those 
two vias was to change clearances from the ground plane.  Did I do 
anything wrong?  This cost $50 because the board fabbing house had to 
review the files again.  It was a high-density board.


Regards,

Gus Fantanas
PS. Yes, I inspected the gerbers before sending them to the fab house, 
the ground plane around those two vias did look a bit odd, but I trusted 
gEDA.  :)

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