Is the bridging occurring between connector pins?
What is the make and model of the wavesolder equipment?

It sounds like the problem might be caused by a area which is not being
fluxed. No flux always makes the solder icicle directly to the mask.

Are there solderballs on the board, and if so, are they attached or loose?

The more details the clearer the picture would be.  It the machine is an
Electrovert with an Omega wave attachment (lambda or contour wave), let me
know as there is a known assignable defect cause of bridging that I can
elaborate more on.





At 7:36 AM -0400 4/23/97, Elizabeth Falk wrote:
>Dear Technet,
>I have a customer who is reporting bridging on the solder side of the board
>after wave soldering.  I have seen the boards, and they look quite messy,
>with solder sticking to the mask as well as between component leads and
>pads.  The mask itself is adhering nicely.  The mask is PC501 from Haven,
>with C101 hardener.  This was recently discontinued by MacDermid and picked
>up by Haven.  The flux is no clean, ENFLUX NCF-8660, and is under pressure
>with nitrogen.  The wave itself is at 500 degrees F, with preheats set to
>get the board to 210 to 220 degrees F when it hits the wave.  The same
>design board with LPI ran fine, so I do not suspect a problem in another
>area of the process.
>
>No other customers are reporting this problem, and I am at a loss as to
>where to investigate further. The customer is not happy, and wants a
>resolution today!  If anyone has any insights, please let me know.
>
>Thanks,
>Elizabeth Falk
>Process Engineer, Beaverbrook Circuits
>
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Regards,


Phillip A. Bavaro
Senior Manufacturing Engineer
[log in to unmask]
(619) 658-2542


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