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I was trying to solder a new capacitor on my pcb and I had problems. At the end I think I burned the copper under the pcb mask and I am wondering if i totally destroyed my pcb. Here is a picture:

where u can see at the photo the brown stuff used to be a little copper which during the soldering just popped out almost burned.

the brown is plastic.

the up brown is the + of the capacitor and and the down brown is the - of the cap.

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    \$\begingroup\$ The first letter of a sentence is capitalized, and "u" isn't a word. \$\endgroup\$ Commented Nov 7, 2012 at 23:51
  • \$\begingroup\$ Evolution - The gradual development of something, esp. from a simple to a more complex form. \$\endgroup\$
    – NickHalden
    Commented Nov 8, 2012 at 0:06
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    \$\begingroup\$ The "up brown" and the "down brown". There is something disturbing about that. Scrape the soldermask at the edges to expose solderable copper. Once you get the cap back on there, don't touch it. \$\endgroup\$
    – Samuel
    Commented Nov 8, 2012 at 1:00

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You applied too much heat to the pads and they became detached from the underlying substrate (most likely fiberglass, not plastic).

I would use much less heat in the future and work at a quicker pace.

To fix, find the traces that would have gone to those pads. Scrape away some of the soldermask on these traces so you can solder to them.

Since the board is damaged, it's probably a good time to get creative to fix it. It looks to me like the traces are very near the damaged pads. I'd scrape some of the soldermask off and orient the capacitor such that it touches both newly-scraped trace. Then solder on a blob at each end .

Here's what I mean:
enter image description here

Scrape the dark green area to expose copper. Position the cap (if you are committed to using the original part - you can also replace with a leaded through-hole component and bend the leads to fit) so it will make a connection between the two. Also, it looks like the top trace continued where the lime-green box is, and is now broken. You will want to scrape away the solder mask there as well, and bridge the two traces.

Take this with a grain of salt, as I do not know your design or board layout and I'm just making guesses how to repair this exact board. I'm just offering techniques on how to remedy this in general.

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The photo is pretty poor quality, and it's not clear what it's supposed to look like. However, such things are not hard to fix. You may possbily have broken a trace at top to the left of the little "+".

PCBs make provide nice convenient pads for attaching parts too, but especially for a one off, you don't have to use them exactly as intended. Sometimes you can use a leaded part so that you can bend the leads in strange ways to hit the pads and replace broken connections. Worst case you can bridge any broken traces by soldering wire accross them, and solder wire to the pads and then connect the part to the other end. Keep those wires as short as you can.

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