Designers love to do BIG copper pours for several reasons: * Maximize heat spreading. * Increase EMI shielding. * Laziness.
The poor folk that solder the parts on boards HATE big copper planes near solder pads. During soldering, fat copper traces [or direct connection to the plane] suck away the heat that is supposed to melt the solder to form the electrical joints. So boards have lots of opens, partially-formed, or intermittent solder joints. Solutions available to these folk are hazardous: * Dialing-up the heat in the soldering machine to overcome this heat-sinking effect can damage the board or components. * Doing post-machine rework can damage the copper plating on the though hole wall, because it is very easy to overheat a solder connection that doesn�t solder well.
Your board designer needs to give you thermal relief on the pins that are giving you fits.
Thermal Relief. [1] Disconnecting the solder pads from the copper in the board ground plane, as much as possible, using the thinnest possible traces that will carry the electric current. [2] A wagon wheel-shaped relief pad etched in the copper of a ground plain around a through hole. Without the thermal relief, the plane robs the component pad and component lead from the heat required to fully fill the solder joint.
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