The Flat Spot Tool

I made this tool ages ago for a different wheel, but it's nice to get a photo of it and document the process.

It's dreadfully simple.  When you get a flat spot on your rim, you need one of these to punch it back out again.  It's welded out of bike bits and some threaded rod.  Do up the nut to push the rim away from the hub (until it expands more than it was flattened) and let it sit for a while.

You can also do it with a rubber mallet and a good eye, but this is simpler and tends to work better.