Hi Carrie,
These were hand soldered using a RMA flux. The plating wasn't damaged in my
opinion, how does tin plating become damaged by coating it with solder? Yes,
the thickness was increased, but that's why I say it surely didn't degrade
the interface between the mating header and the contacts.
This wasn't a widespread problem. Occasionally, the operator may have spent
a little too much time over a pin with their soldering iron trying to fill the
extra space in the oversized hole with solder, which allowed heat transfer
to occur throughout the pin and allow the solder to flow up the pin. Plus, the
oversized hole reduced the capillary forces that are available allowed the
solder to flow up to the contact area. How many times have you seen solder
just drop out of a oversized hole during wave solder? That's my take on why it
happened.
But I still don't think the entire socket needs replacing if we removed the
solder so that insertion of the header is accomplished.
-Steve Gregory-
Now Steve...You KNOW the customer is ALWAYS right, except for when we
need to educate them.
First, I would ask the customer WHY the rework is unacceptable.
They may actually have a valid reason.
Next, I would educate them. They may be concerned about flux getting
into the connector. Are you using OA or NC? They may be concerned
about damage to the plated surface. They may be trying to punish you
and teach you to do things right the first time even though we all know
people do make mistakes.
-Carrie
-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory
Sent: Wednesday, November 24, 2004 12:10 PM
To: [log in to unmask]
Subject: [TN] Samtec PCS2 Socket issue...
Hi All!
First of all, I would like to wish everybody a safe and happy
Thanksgiving!
I have an issue that I would like to bounce off of you all. We're
building an assembly that uses some Samtec "Power Combo Sockets", here's
the *.PDF link to it:
_http://www.samtec.com/ftppub/pdf/PCS2.PDF_
(http://www.samtec.com/ftppub/pdf/PCS2.PDF)
Due to the design of assembly, we had to hand solder these in. The hole
diameter in the board for the power pins of these sockets are .072",
Samtec recommends .058".
We experienced some sockets that had solder flowing up into the power
pin contacts to the point that prevented full insertion of the mating
header, so we removed the solder to allow full insertion using a solder
extractor.
The contacts for the power pins are Tin plated as you can see from
Samtec's drawing, so there really is no contamination from the solder
as there would be with gold plated contacts which the signal pins are
plated with
Now we're being told that our rework was unacceptable, and that the
sockets need to be replaced...I don't see what we did affects the
performance of the socket in any way.
If the mating header can be fully inserted, then electrical contact
should be fine in my opinion. If anything, I feel that the electrical
contact may have been improved slightly due to the tighter fit between
the header pin and the socket contact...it surely isn't degraded.
Am I out in left field about this?
I really appreciate any feedback!
-Steve Gregory-
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