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Date: Thu, 27 Feb 2014 15:15:48 -0500 (EST)
From: Stuart Brorson <sdb AT cloud9 DOT net>
To: geda-user AT delorie DOT com
Subject: Re: [geda-user] Via under a pad?
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Precedence: bulk

Yes, it's generally bad practice because the vias will suck solder
down into the hole and away from the pad during reflow.  This will
leave the part with little or no solder holding it to the board.

If you do want to do it, you need to calibrate the amount of solder
paste placed on the pad to accomodate for the fact that a variable
amount of the solder will go down the via hole.  Not a good idea to do
this in general since it's hard to gauge the solder loss accurately.

Hope this is useful,

Stuart



On Thu, 27 Feb 2014, Rob Butts wrote:

> Is it bad practice to put vias under pads?  These pads are twice as big as
> the vias.
>
> Just curious.
>