Steve,
You might tell them you have reduced the possibility of "tin whiskers"
with the solder.
David A. Douthit
Manager
LoCan LLC
Steve Gregory wrote:
>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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