Copper pads on printed circuit board came off.

[topfli8979]

I was in the process of removing some fets on a printed circuit board, and I guess applied to much heat. The copper pads on the top and bottom came off the board, and are were destroyed. Now I cannot get the solder to adhere to the board properly. Is there a fix for this, or do I have to replace the board?

[tom66]

Re: Copper pads on printed circuit board came off.

You need to find the nearest copper connected to that, and strip the soldermask off, then solder to that. Pictures of the board would help.

[topfli8979]

Re: Copper pads on printed circuit board came off.

Here it is.

[tom66]

Re: Copper pads on printed circuit board came off.

You need to get a more in focus and closer picture, we need to be able to trace it through. Maybe you will have to remove some of those green caps to get access.

[topfli8979]

Re: Copper pads on printed circuit board came off.

sorry ffor delay, been out of town. Here is a closer more focused picture.

[mariushm]

Re: Copper pads on printed circuit board came off.

The trace goes from R5082 (the one below the text saying q5006 or q5008) to the hole .. carefully scrape off the insulation on that trace.
Get some thin wire, lay it over the trace so that one end is almost near the resistor solder, and the other side goes down into the hole. When you put the mosfet or whatver that was on the heatsink, its lead will press against the wire and will make good contact.
Now solder the wire and lead together and the wire to the wide trace (if you want, add a bit of solder to the resistor side and then solder the wire to that solder)

[topfli8979]

Re: Copper pads on printed circuit board came off.

Ok, what about the other hole on opposite side of the FET, or does it all trace back to one source.

[mariushm]

Re: Copper pads on printed circuit board came off.

Well, no offense but are you blind or unable to check? I can't see better than you from here.

I've explained how the first one works, follow the process the same way for the other.
Look around the hole for lighter green stuff, that's the copper trace under the insulation. Scrape that off and repeat.

[topfli8979]

Re: Copper pads on printed circuit board came off.

That is why i was asking if it is possible for both sides to come off one source, the opposite side does not have a lighter green trace.

[mariushm]

Re: Copper pads on printed circuit board came off.

Yes, it does have one.

All three holes have something, if not on the top, on the backside.

On the far right hole, there is something that looks like a trace going diagonally towards the corner of that white rectangle. I may be wrong and it could be just a reflection.

The center hole's trace may be going behind the heatsink under that thick white bar, or both center and right hole's traces may be on the other side of the board.

Just get some flashlight or some desk lamp and shine the light through the board and you'll see the traces, if you can't see them with your eyes alone.