Four corny kegs arrived this week. They were in great physical condition but covered in years of sticky coke syrup.
I cleaned them removed all the stickers and still gunky.
So I busted out the orbital sander. Started with 180 grit, I cleaned em up, went to 320 grit, then ended with 600 grit. They look like new-ish. They are still old soda kegs, hope they like a soft end to a long life.