Hi Paul,
We run our solder pot at 465degF with no problems - but our assemblies have a relatively low thermal mass.
Check for:
1. Solderability of PCB
2. Solderability of components
3. Flux correctly titrated and applied evenly, but sparingly
4. Preheat PCB to 210-230degF topside
5. Dwell time in solder 2-4 secs at a reasonable depth (50-75% of PCB thickness)

Have fun!

Justin Braime
Process Engineer - Compuspec Industries
1a Niall Burgess Rd, Mt Wellington
Auckland, New Zealand
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ICQ# 54138771
Ph: +64-9-574 1990
Fax: +64-9-574 1988

----- Original Message -----
From: Paul Tomlinson
To: [log in to unmask]
Sent: Thursday, November 11, 1999 4:56 AM
Subject: [TN] Voids after Wave-Soldering!


Hi folks,

I am just learning about these matters, and this is THE place where
knowledge and experience abounds so please somebody help me with this.


I have just had my first ever boards waved and the results are not
encouraging.  What could be the cause of a volcano shaped void between the
component leads being soldered and the main body of the solder?


There is perfect continuity, the area at the tip and that around the board
are well wetted, but mechanically the joints are very weak and prone to
failure, the parts can actually be pulled out of the board without being
damage.


Could this be simply the result of a too low temperatured wave?  They used
465F.

                       |       |
                       |       |
                       |       |
--------------------- |       | -------------------
                     | |       | |
                     | |       | |
                     | |       | |
--------------------- |       | -------------------
           *         * |       |  *         *
          *         *V |       | V *         *
           *       * O |       | O  *       *
            *      * I |       | I  *      *
              *    * D |       | D  *    *
                *   *  |       |   *   *
                  *  * |       |  *  *
                    * *|       | * *
                     * |       | *
                      *|       |*
                       ---------

This ASCII art is extremely crude so I have attached both JPG and BMP files
of a much better drawing.

Tia,

Paul.



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