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Default Repairing flat cable


"isw" wrote in message
]...
In article ,
"Arfa Daily" wrote:

"isw" wrote in message
]...
In article ,
"N_Cook" wrote:

isw wrote in message
]...
I have a piece of gear that uses a "cable" consisting of printed
circuit
traces laminated between two pieces of dark orange plastic
(Kynar???).
The cable was torn in two, and I need to repair it. If I could
remove
about an eighth of an inch of the insulation on one side of each
end, I
could lap them and solder the conductors. The plastic it totally
resistant to every solvent I have on hand, and a 750F soldering iron
has
no effect.

Does anybody know of a solvent for the plastic, or some other way to
strip the traces?

Isaac

A small cylindrical centrided burr in a dremmel can be useful for
stripping
back, surprisingly controllable if you hold it the "right" way round
so
it
doesn't skud.

Or make up some fine wire plaited braid to replace the whole thing

It's in the lens assembly of a small camera. The cable is less than
0.25
cm wide, and has twelve conductors (I had to use a loupe to count
them).
Making a replacement is probably not in the cards.

Isaac


Don't you just HATE that sinking feeling you get in your stomach when
something like this happens, especially when it's a customer's unit ...
:-(


Yeah, and especially because I've fixed two of these cameras previously
(there's a design weakness in a supporting strut inside the lens; a bit
of brass tubing and some epoxy is all it takes). This time, the strut
was fine but somebody had spilled something like orange juice in the
camera, and the moving parts got all gunky and sticky. I think that's
what tore the cable.

Long experience of working with flexiprints of all descriptions, leads me
to
believe that you are really going to struggle to reliably repair one that
small and fine-pitched. I suppose it would be really silly to ask if
there's
any chance at all of getting a replacement ?


The only way would be to get a good cable from another scrapped out
camera (which this one now is). The cable terminates on the "sled" that
carries the anti-shake lens, and the driving coils for that are etched
right onto the orange plastic substrate; there are not any "terminals"
to attach replacement wires to...

Isaac


Ah well, some ya win, some ya lose ... At least if the owner has filled the
thing up with juice, there's justification for declaring it BER, and at
least it's not a problem that you have caused whilst repairing some really
simple thing. That one's the killer. When you've fixed the dirty volume
control with a lttle squib of switch cleaner, and then you drop your
screwdriver into the output stage ... :-\

Have a good 'un

Arfa