Great instructable. My experiences with it:

1. Don't get bogged down in the exact ratio of citric acid (I used food grade powder from Amazon). On a couple of occasions, I used a higher concentration than the author: about 1:8 to 1:10, measuring both the powder and the water in a typical measuring cup. It worked great although I never saw much bubbling at all.

2. I used a small brass-bristled brush and as the author says: Scrub, Wait, Scrub some more. Or just be patient and leave in longer; but scrubbing is definitely going to speed the process.

3. My biggest challenge was finding a container that was long enough and shallow so that I didn't have to use loads of solution. Finally came up with a flimsy plastic one that some pastries came in. Used it for about 10 items.



Discovered that some old tools had lettering embedded in them that I didn't even know was there!