Blanchet,Richard wrote:-
>Hello,
>
>This question might sound pretty basic to many of you but here it is:
>
>We have a brand new wave soldering machine but we are having problems
>getting rid of bridges. We tried to increase (or lower) conveyor speed, add
>more flux, lower the wave, but nothing seems to work. Rotating the PCB 180o
>doesn't help either. The bridges are either in the X or Y direction
>(sometimes both) and, in one case, the connector leads have a pitch of about
>0.080".
>
Hello Richard,

It sounds as though this might be temperature related and the connectors
are cooling the solder too rapidly.

Just a few thoughts. Look critically at the wave. I like a dynamic
leading edge with a rapid flow rate with the trailing edge almost static
to wick off excess solder as the board exits. Check the temperature of
the solder along the wave to ensure it is hot enough and has an even
temperature. Try and increase the contact time in the wave by lowering
the conveyor or raising the wave height, and try to get at least 2-3
seconds of contact with the solder.

If the soldering parameters are correct then the holes should fill with
solder. If this is happening in other areas but not on the connectors it
may be the connector lead solderability or just a heat sink effect..


Paul Gould
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Isle of Wight,UK