Mr. Gregory,

I would like to use a pre-formed tab to minimize labor costs and to
compensate for the 'lack of dexterity' the people who will actually be doing
the rework have (or don't have).

As far as 'wanting to add extra volume to the spheres' I think that I lack
the eloquence (or technical wordage) to put it differently ;)

The parts I want to replace are BGA CPU sockets (Pentium 4, Socket 478)
which have SMD capacitors soldered to the PCB, in the center area of the
socket.  A preformed tab, if such a beast exists, would save us the
time/cost of removing/replacement the components to avoid stencil co
planarity issues.

Thank you for your response.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Steve Gregory
Sent: Friday, April 02, 2004 12:18 PM
To: [log in to unmask]
Subject: Re: [TN] BGA socket placement

Hi David!

Not sure quite you mean when you say; "Pre-formed tab to add extra volume to
the spheres." Can you elaborate further?

You also say that you want to avoid adding solder paste, can I ask why? If
the ball-pitch, ball count, and ball pattern is pretty standard, you can buy
10
Flextac stencils from Circuit Technonolgy Center for around $50. They work
wonderfully too! Go to:

http://www.circuittechctr.com/products/201-3120.shtml

and check them out. I've got pictures up on my page of me using one to
solder
a Power PC BGA to a SMT-to-PTH adapter, which I'm sure if there wasn't
something like Flextac stencils around, would have been a real bear to do.

Give us a few more details...

-Steve Gregory-


> Hello Technetters,
>
> I have some BGA sockets which I am trying to solder to PCBs.
>
> The sockets have stand-offs which prevent the solder spheres from
collapsing
> and making a good mechanical/electrical connection.
>
> Ideally what I am looking for is a pre-formed tab to add extra volume to
the
> spheres.  I do not have an in-house machine shop to make a stencil to
apply
> paste and quite frankly I would like to avoid that course if possible.
>
> Thank you in advance for your help,
>
> David Tremmel
> Technical Manager
> Belmont Component Services
>


---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to
[log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to
[log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16
for additional information, or contact Keach Sasamori at [log in to unmask] or
847-509-9700 ext.5315
-----------------------------------------------------

---------------------------------------------------
Technet Mail List provided as a service by IPC using LISTSERV 1.8e
To unsubscribe, send a message to [log in to unmask] with following text in
the BODY (NOT the subject field): SIGNOFF Technet
To temporarily halt or (re-start) delivery of Technet send e-mail to [log in to unmask]: SET Technet NOMAIL or (MAIL)
To receive ONE mailing per day of all the posts: send e-mail to [log in to unmask]: SET Technet Digest
Search the archives of previous posts at: http://listserv.ipc.org/archives
Please visit IPC web site http://www.ipc.org/contentpage.asp?Pageid=4.3.16 for additional information, or contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315
-----------------------------------------------------