Hey all- We use selective wave solder pallets extensively to solder through-hole leads, as almost all our boards are mixed tech. A couple types boards consistently show a single short on the trailing edge of large through-hole connectors. One board always shorts on the trailing pins of a PGA socket, while the other always shorts on the trailing edge of a 40-pin dual-row female header. No amount of tweaking the wave machine settings affects the short. My theory is this: When the solder leaves the larger pallet openings, it has nothing to "snap" to. Therefore, it "snaps" to the last couple of pins it leaves. I have made sure that the solder flows off the back of the wave at the same speed as the conveyer. Has anybody else seen, or heard, of this problem with selective solder pallets? The advantages of reflowing bottom-side components make wave soldering the whole bottom-side unfeasible. Speaking with the pallet house has left us with grooved pallet bottoms and chamfered openings; but the problem remains. Is there a way to alter the selective wave solder pallet openings to avoid these "snap-back" shorts?