What to do with this burned board

[glebert]

Hot Rod Deluxe that someone kept pumping fuses into. Amp is mine now so I can do whatever I want with it. It looks to me like the burn material goes pretty much all the way through, so I assume I am going to have to cut out a section. I'm a bit worried if I cut out the burned section that it will weaken the whole board, and the preamp tubes on the left side don't have great standoff mounting. Any tips?

[The Dude]

I'd cut it out and run appropriate jumpers. IMO, the standoff near the burnt part of the board should be enough to provide stability.

[eaelec]

I would not cut out the burnt area, I'd replace the burnt resistor with a chassis mount type (if the correct resistance value is available) and run wires to the solder side of the board. Then repair any other damaged traces with wire jumpers as The Dude said.

[olddawg]

If you can’t find a piece of junk board to use, use perf board. After you cut the burnt part out use the piece as a patch with 5 minute epoxy. Then run your numbers across it. I’ve done this many times and it really helps with the board integrity. It’s best to cut it out with a hole drilled in each corner first. It will keep it from cracking. I usually used a Dremel with a circular cutting blade to cut out the area.

[SoulFetish]

I would not cut out the burnt area, I'd replace the burnt resistor with a chassis mount type (if the correct resistance value is available) and run wires to the solder side of the board. Then repair any other damaged traces with wire jumpers as The Dude said.

You can’t keep that carbon on the board, it is conductive. There are high voltage traces running through the affected area which is now contaminated.

[Mick Bailey]

+1.

You have to cut out that section entirely otherwise it will fail again. Firstly, photograph and draw out the traces so you know exactly where everything needs to go.If you're concerned about the board integrity you can epoxy in a piece of plain FR4.

I've had them burnt so badly I've had to cut off the end of the board and mount new octal chassis sockets and wire up a new power amp section on tag strips. There aren't too many components.

Edit: Just noticed olddawg had already mentioned patching the board.

[Chuck H]

Posts 4 and 6. There's always a way to reinforce the board. Of if not then a way to stabilize the tube socket. A lot of epoxies soften with heat. And not always a lot of heat. So do check that figure before settling on any adhesives.

[glebert]

Thanks for the replies. I am definitely going to cut out the section and epoxy in some perf board. That will give me a place to mount those couple components and give the board some strength.