So I finally got around to brewing my first BIAB this weekend. This was also my first all grain. I would like to thank kartoffel for making this possible.

Mashed 2KG of Maris Otter in 16.6L (20C) of water.
Pre-boil volume was 15.53L (100C) @ 1.034 SG

26G Fuggles (4-5.5%AA) @ 90min
10G Fuggles (4-5.5%AA) @ 10min

Post-boil volume 11.17L (100C) @ 1.050 SG
8L in Fermenter with 4L foam on top. So 8.01L perhaps ... including 1-2L of trub at the bottom

The hydrometer sample tasted good... a bit more bitter than I expected, but still good.

2KG of grain... 6-7L of beer I'm happy.

Lessons:
11L of boiling water takes a long time to cool off in a water bath with no ice.... I need to make some ice next time. I gave up once it got to 25C

I'll try a hop bag next time... lots of green sludge at the bottom of the kettle. The worst is the fluffy stuff (break material?)

Questions:

1) During the mash the grain bag was dripping out of the pot. There was a few centimetres of head space but it was wicking up some water and dumping it all over my stove. So I had to keep wiping it up the whole time. I was guessing I lost a 2-3 cups of liquid over the 90 minutes, but the measurement I took don't show that. I.e I lost ~1L including grain absorption. Is the dripping normal? How can I stop it?

2) It took a long time to cool down the hydrometer samples... I put a cup in a water bath in my freezer with a few ice cubes in the water bath. Is there a secret faster way?

3) My gas stove was at max for the whole boil. I floated a bowl for a while and I got the knob down to 3/4 with a still having a vigorous boil. So bowl or no bowl? Evaporation was 4.36L according to my measurements. The calculator says the boil off should have been 5.56L for my 33.2CM canning pot. I'm trying to gauge what my max batch size if on my stove.

4) There was lots of trub in the Hydrometer jar... especially the post boils one. more than half the jar after settling for 5 minutes. Does it make a difference?

5) I think I got 6-7L of clear wort in the end... Then I panicked trying to get more and I syphoned most of the liquid trub at the bottom (break material?). Question is is getting 3-5L of trub on that size batch normal of should I have let it settle longer?

Sorry for all the question.

Congrats that it went well. Wirfloc tablets at 15min to end of boil and a good stir and long wait usually help make the wort pretty clear. I try to take my sample from the clear wort after it has settled. I do chill with an IC though as I'm worried about what happens to my flameout hops since most of my beers are hoppy (I guess this is negligible for some people?)

1. maybe hold back some water from the mash and do a maxi-biab or just add water back to the boil depending on your efficiencies.
2. I get mine down to about 80-90 and then use temp correction to save some time.
3. You can adjust your boil off and compensate for it. I'm not sure if the calculator you have adjusts for that, but I'm sure someone else could elaborate on that for you.
4. I don't know but I have had it happen before and never felt good about it. I really try not to have that happen these days. For preboil it's pretty hard though I never have clear wort pre-boil and only have had really clear wort post-boil when I waited a good long time and used a whirlpool and wirfloc.
5. I try to wait as long as possible but I frequently do get some of that fluffy stuff (which I have only ever seen in BIAB) into my carboy. Perhaps it's good for the yeast but it takes a lot longer IMO for the beer to clear up in the carboy then. I use gelatin which seems to help a little bit though.