Did my first AG today.
Last time I brewed, I did a PM and got around 65% efficiency, so I figured I should have about the same efficiency. Nope. Last time I brewed, I had a boiloff of 1 gallon/hr, so I figured I should have about the same boiloff rate. Nope.
I got a 75% efficiency and a 1.3 gal/hr boiloff. So I was really going mad on Excel trying to figure what volume I should add/have at the end. I decided to increase the volume by adding water (larger batch volume to compensate for bigger efficiency + bigger boiloff ) and to increase the amount of hops (to compensate for the bigger batch volume). I forgot to add my immersion chiller @ 15 minutes... but I remembered @ 10... My thermometer got stuck for about 1-2 minutes, so my mashout was @ 177 instead of 170 so I removed the grain as fast as possible when I realized that (probably was at 177 for max 2 min).
And I think a minute amount of the black dust forming under my kettle while it is used went into my beer.