New to the site however I've been playing with recipes here for a few months and just never tried getting my beer nerd brew day info correct. I'm having trouble fine tuning my equipment profile and understanding what factors affect the preboil amount. Don't know if this helps figuring my issues but I BIAB in a keggle and have figured most of my numbers by entering past brews into the brew day and going back and forth tuning them so the site hits my numbers I've recorded. I've figured my grain absorption is between .5 and .6 qt/lb and this typically gets me to what my starting water amount was in the brews. Problem is the preboil water amount seems about a 1/2 gal lower than what I physically have had in the keggle and wonder if anyone can help me or point me to a tutorial that explains everything. Eg: 11.88lb grains into 8.9 gals of water. BF preboil says it shopuld be 7.4 gal however I had 7.9 gal. I've tried to figure it out myself for the last few days playing with the numbers, reading the forum and FAQ and know I must be close, just not quite there yet and need someone to "talk me off the ledge" before I say to hell with it. Could it have something to do with the kettle dead space? I haven't played with that yet. Sheesh!