To set the scene, I have a slightly dodgy home-made mash tun with a false bottom a bit like this:
http://www.instructables.com/id/Build-Y ... 0-STEP-1-/
It holds it's heat well though for 90 mins and has produced some good results so I don't knock it - it's the workman not his tools going wrong here I think! Under the false bottom it holds approx 3 litres. The dead space (what doesn't drain isn't much so I'll say approx 0.5l for example's sake)
For illustration purposes, please assume I'm aiming for 23l final wort to brew, made with 4kg grains. (So I probably need approx 28l to boil.)
So, questions:
1. How much water to use for mashing? I've seen reference to using anywhere between 2-3 litres per kg. So assuming a 4kg mash, between 8-12 litres. I assume I shoudl also factor in the 3 litres under the space to 11-15 litres in reality? Any ideas on best ratio or is 2.5 l/kg as good a starting point as any other?
2. This is where I really think I start to fall down. With this type of mash tun what's better - fly or batch sparging? I have been attempting fly until now, slowly pouring over the grains for ages and draining very slowly. It's taken ages - well over an hour and I suspect I'm not doing it 100% right. So I'm thinking I'd like to try batch...
3. I assume next is to drain my existing mash - does this need to be done slowly or a particular rate?
4. Does any need to go back in (lautering?) and if so how much? Just once? What's the idea behind it?
5. If attempting a batch sparge, what next? 2 equal volumes are best apparently? So My initial drain on a 2.5l/kg mash might be approx 13l less 4l grain absorbtion and 0.5 l dead space = 8.5l. So allowing 2 batches of 10l would be okay to get approx 28l at the end? How long should the batch sit for and should it be stirred at all or just left? Should any go back in as per q4 above?
6. Presume the 2nd batch should be as per the first?
7. Any other comments/suggestions?
Thanks in advance.
