Fixed a weird failure on my Nikon MH-18a charger

Here's the back of the board.

And the front of the board. Big, heavy parts like C4 aren't glued down...

The gobs of ugly glue you see on many cheap one-sided paper phenolic circuit boards like this (and AV equipment and power supplies) helps prevent the following problem due to the lack of plated-through holes to hold parts in place.

Metal fatigue!

The copper around the pad on one of C4's legs fatigued. A little scrape with a penknife and a dab of solder later, and works like a charm.