Again, if you know what you are doing, it only takes a few minutes to
brighten up a chain. Now, mind you, I'm not talking about a chain that
hasn't been sharpened in a long time, that takes time to regrind into
decent shape. I was taught early in life that if you file your chain
often, it doesn't take but a few minutes, and makes cutting SO much
easier. If you let it get dull, then it takes a long time to file
sharp.