[sdiy] SMD experiences

[Colin f]

> What's a "thermal relief pad" and why would I only need one 
> for through-hole?

If your thru-hole has no relief, it can feed too much heat into the inner
layers, increasing the risk of de-lamination.
It can also suck too much heat out of the joint during soldering, causing a
cold joint.
This applies to fills on top and bottom layers too, particularly where you
have a component that can soak up a lot of heat itself, such as the legs on
a vertical pot.
Maybe not so much of a problem where you are hand, rather than
wave-soldering.

Cheers,
Colin f