Mysticmead

Recipes 

weight of grain x absorption + boil off +trub loss + batch size = water needed.

try 10.5 x .074 + boil off + trub loss + batch size.

for me that would be 10.5 x .074 =.777 (round it to .75 gallon) + 1.5 gallon + .25 gallon + 5.50 gallon = 8 gallons of water needed. now of course that won't fit you 7.5 gallon pot much less the grains. What I would do it have 4 gallons of water in the 7.5 gallon pot, add the grains and mash, then transfer to another pot with the remaining water to dunk sparge. or get a bigger pot

jr14

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Thanks mysticmead. I actually read all 42 pages and I know this is approximately the tenth time you've posted that equation.

I actually have it on a post it note on my wall.

I'm going with your equation.

jr14

Recipes 

Well, I feel a little silly. I can always bring 6 gallons of water up to mash temp, then slowly add the grains. If the water gets too high, I can just open the spigot and let some water out.

Then I can heat my 2nd kettle of sparge water, and top up after the mash in complete.

stux

Recipes 

Better to take the water out first, put it in your second pot, add the grains, then add back the water.

I don't know it in US units, but grain displaces about 0.7L per KG.

So

Max Strikewater in L = Max Volume of Kettle in L - (Kilograms of Grain * 0.7)

Then when you've worked out your total water, subtract your strike water volume and use the remaining water to sparge with, doing it this way should get you 80-85% efficiency into your kettle

__________________
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jr14

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Thanks stux. In US, Your equation looked something like this to me.

Converted Grain Displacement .18 Pounds per gallon

Max Strikewater in Gal = Max Volume of Kettle in Gal (7.5 for me) - (Pounds of Grain (10.5 for me)* .18)

This = 1.89 Gal (I rounded up to 2). So I'm going to start with 5.5 Gal.

Riseabovebb

Recipes 

Hey all - looking for some help regarding my ability to brew the HopSlam clone recipe offered by Schweaty. Looking to do this as a no-sparge, but not sure if I have the capacity.

What I have available:

44Qt Bayou Classic boil kettle (with matching basket)

Grain bill per Schweaty is 19.5 lbs. with a starting boil size of 7.11 gallons. I used the formula offered by MysticMead a few posts above to determine my strike volume and came up with 8.69 gallons (I used Mystic's trub and evaporation figures as I'm new to BIAB).

I've looked at the 'Can I Mash It?' calculator on rackers.org (Green Bay Rackers--Mash Calculators), but I'm not 100% sure of the mash thickness ratio. I know I would enter 19.5 in the weight field. For the mash thickness, would I take 8.69 Gallons x 4 = 34.76 Qts and divide the 34.76qts by19.5lbs to get a 1.78 mash thickness ratio?

Using 19.5 lbs and 1.78 mash thickness ratio in the calculator tells me I would need 10.24gallons worth of space. If my math is correct, and 10.24 gallons of space is needed, should I attempt this (no sparge) in an 11 gallon kettle including the basket? I'm I asking for trouble?

Thanks in advance!

Matt

Antler

Recipes 

What I did when doing my first BIAB 6 gallon batch, was mash with ~4 gallons, then topped up to my pre boil amount after the mash.

JimTheHick

Recipes 

Or sparge with the two gallons. It's often mentioned that BIAB is no sparge, but damn it's pretty easy to pour the extra two gallons back through the bag while it rests on a grate over top of the kettle while heating to boil.

Seven

Recipes 

I brewed this exact same recipe using a 10-gallon kettle. My kettle was definitely maxed out but it worked. This turned out to be one of the best beers I have made so far. You should be able to do it with your 11-gallon kettle.

jr14

Recipes 

This is exactly what I was going to do as I had it suspended above the kettle.