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Repairing or gluing a broken PCB board and circuit traces

Not bad work.
I would have been tempted to go point to point on some of those, especially with such long leads protruding from the board.
 
I never cover, top coat the work with anything.

Good solid wire holding onto a trace or pad has always worked in the past for me.

Could always add some solid wire into the shielding ground portion on the board to reinforce.
 
Your work looks very good.
Just to confirm, did you scrape the insulation off of the etch runs before soldering with the wire? A few of your connections don't seem to have the solder flowing through under the entire copper wire jumper runs.
 
I agree also that you don't need to do a conformal coat, or another leayer of epoxy on top. As long as the board has been bonded with CA, and you have scraped the etch runs and soldered across each break with reinforcing copper wire, and you install the board with all the right hardware, you should be fine.
 
Something to consider:
If you can drill small holes on each side of the crack AND find an epoxy that will 'flow' through the holes, that will anchor the epoxy, especially with epoxy on both sides of the board. See attached pic

Looks like you were able to use a large gauge wire for bridging, which should provide a mechanical link. With fewer broken tracks I have used #26 or #30 solid insulated wire to run "lead-to lead" jumpers to protect the circuit from later breakage.

Well done - - -
 

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dlucy said:
Edges held together with hemostats and instant cure (thin) CA applied. That worked well.

Bridges made with solid wire and solder. Not pretty but solid.

View attachment 1601147
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Now to make a plan on how to apply (and fence-like retain) 30 min epoxy on top of all that.
Click to expand...

Nice job! With the CA glue, and the "jumpers" soldered completely across the cracks with no gaps, the jumpers themselves will provide a lot of "reinforcement". If you have any "donor" boards around, you can cut some pieces to use as "splints" and epoxy them over the cracked areas sanding off any "coating" or copper for best adhesion. I "sandwiched" some cracked boards with pieces on both sides of the board for extra strength. The ends look like wide ground areas and won't hurt a bit to "sandwich-splint" them. With all the screws in place it should hold up just fine **as long as the RCA cables used do not plug in hard. Some are too tight and extra force is needed to insert them. If the owner's cables fit too tight, recommend replacing them, or if possible, "adjust" them so they plug in easy.
 
Good thought re: being able to sacrifice some of that ground area for splints. There does appear to be more than enough. (Could always jumper the splint w/ a short length of wire, to err on the side of caution.)

I might be reluctant to rely on the wire jumpers to provide rigidity. That transfers any strain to the traces, at the ends of the rigid wires.
I think I'd go as far as to use flexible, stranded wire, and only solder the ends, just to avoid that possibility of tearing up traces if the board sees any flex in the future.

I usually try my best to make repairs look indistinguishable from original, but this is the sort of repair where function should take precedence over form. Far better for it to be solid and remain trouble-free, than to be concerned about it looking "factory."
 
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