District Cutlery did a shockingly good demo of what needs to be done here:

https://youtu.be/fdB8M7h___E

Very similar to my own process. Don’t worry about the thinning yet.

Your knife has a frown, rather than a smile, but the solution is the same. The edge needs to be ground straight into an abrasive until the profile is flat at the heel and sweeps up evenly to the tip. Without a power tool that means sawing the knife into the abrasive, back and forth. Laborious but simple. Then the knife needs to be sharpened.

With this sort of repair work it helps to mark the desired profile with a sharpie before starting, to avoid overshooting.

This is a task where a good sharpening stone won’t do, it gouges the stone. Bricks are cheap and surprisingly abrasive. It’ll gouge the brick, too, but that’s fine.

——

I would consider my time very well spent doing this.

I sharpen around thirty knives a year that aren’t mine and I refuse to commoditize my every breathing moment. I have never asked for a penny for sharpening, it’s pure love of the game.

How I sharpen is also tbh not a great business model, which makes having a moral stance a lot easier.