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channelmaniac
September 2nd, 2009, 03:09 PM
I figured this would count as vintage since SMT chips have been used by IBM since the old PS/2 day. ;)

A customer sent me a board for repair that was damaged physically in shipping. Here's the write up on how I repaired a board that had a surface mount chip scraped off of it - along with most of the solder pads.

http://newlifegames.net/nlg/index.php?topic=61.msg36444#msg36444

Enjoy!

And... there are more techniques in that thread you may enjoy.

If you have some repair techniques you'd like to share, add 'em to this thread and we'll have some documented here for other VCF users!

RJ

Chuck(G)
September 2nd, 2009, 09:22 PM
Nice job!

Now let's see you do the same repair on the big TQFP to the northeast of your repair... :p

channelmaniac
September 2nd, 2009, 10:01 PM
HAHAHAHAHA - no. ;)

I just told a guy last week that a board he sent me was unrepairable. Someone hamfisted a chip into place and there were multiple pulled pads that were pushed sideways and soldered to the next pad.

Sometimes it's just too much work.

However, the difference between that board and the one I showcased the repair on was that the unrepairable board could be had used for less than $60 shipped. The board I repaired is still worth several hundred dollars.

:cool:

tezza
September 2nd, 2009, 10:05 PM
Good advice. Thanks for writing it up.

Tez

Chuck(G)
September 3rd, 2009, 09:29 AM
RJ, you do my heart glad. Too few things are repaired nowadays--they're just placed into the waste stream.

At one time, those in the repair trade were valuable contributors to the economy. Now, that function seems to have been taken over by foreign manufacturing. Maybe the profit margin's bigger. People don't have TV's or computers repaired--they junk them--and yet, most repairs are fairly simple.

We're going to drown in our own garbage.

dave_m
September 3rd, 2009, 12:00 PM
I figured this would count as vintage since SMT chips have been used by IBM since the old PS/2 day. ;)

A customer sent me a board for repair that was damaged physically in shipping. Here's the write up on how I repaired a board that had a surface mount chip scraped off of it - along with most of the solder pads.

http://newlifegames.net/nlg/index.php?topic=61.msg36444#msg36444

RJ

RJ, for high reliability aerospace boards, the specs say you cannot repair boards with "jumper wires" (Air Force worries they will come off under high g's and vibration). But occasionally, we called out for the use of "bonded surface conductors". Of course we do not use nail polish to bond the wires, we call out for "epoxy recipe 63" from our Materials & Process lab. Our fix sounds a lot more formal, but your fix seems just as good. ;)
-Dave

channelmaniac
September 3rd, 2009, 12:21 PM
Thanks!

I just do old computers, game consoles, and arcade games! I try to stay FAR away from things that could cause a life to be taken. ;)

Chuck(G)
September 3rd, 2009, 12:56 PM
Manual rework of PCBs used to be a lot more common, probably owing to the cost of multilayer PCBs (what do you do if you've got 10K of them sitting in the stockroom?) and the cost of layout work (A guy (usually Asian) with a loupe, X-acto knife, tape and India ink cheerfully earning his keep).

One of the Olivetti 286 ISA cards that Lance was offering awhile back has a staggering amount of rework on it. (It's also a bit bizarre in that it was laid out to use either SMT (on the wiring side) or through-hole (on the component side) discretes, with the result that a lot of caps and resistors are buried underneath ICs.)

I'm trying to recall the name of the machine-produced stapled-wire boards done in the 60's and 70's. It seems that the aerospace folks used them quite a bit.