Hi Technetters,

In my haste last friday, I posted this question and after reviewing it,
I realized it was somewhat ambiguous.  Please excuse my reposting, but I
really need some input on this.

My question is:

In testing the lead solderability of a component, if the solder test pot
is a 570 deg, would this be sufficient to burn off oxides on the leads
and give an indication of acceptable lead solderability in the absense
of flux?

We have been having some problems with the vendor who supplies these
parts. The crux of the problem is that when we try to run these parts
through the wave solder machine (pot t=480 deg, noclean flux, sprayed, 2
stage preheat 725deg, Sn63 barsolder), we get certain lots that fail to
solder properly.  The QC tech set-up this procedure last year before he
left and it was in place before I arrived.  His procedure was as
follows:

Apply power to test pot.
Use same bar solder used in wavesolder machine.
De-dross pot.
Dip component leads in solder for 5 seconds.
Evaluate part.

For the most part, this has worked.  However, when I took over the
responsibility and found that the procedure had no traceable standard, I
could not get our claims of unacceptable solderability to stick.

In an attempt to validate the current procedure, last year, I sent a
sample of resistors from a lot that failed to an outside lab and they
confirmed the indication of failures.  We used ANSI J/STD-002 test
method A.

I have evaluated ANSI J/STD-002 test method A ( I have not had time to
find out if there is an appropriate IPC standard) and we will be using
this, but the vendor is screaming because we were not using a "true"
procedure.  I am having difficulty getting the vendor to fix the problem
without some sort of traceable standards.

My findings point to the wire stock that is being used is old and has
been exposed to moisture and other atmospheric contaminants and the wire
has oxidized, causing poor solderability.

Any input will be greatly appreciated, since I have to meet with the
vendor tomorrow to resolve this.

Thanks in advance,

Jared Lang
Manufacturing Engineer
Minarik Corp.
Glendale, CA.
818-637-7434