Matt...

You're really in the guess-timate zone doing it this way. What you'll be
doing is taking two gravity readings and then coming up with something
approximating an average. You're really much better off doing a slow,
steady sparge and collect the runnings in one boilpot. Many years ago I
tried doing something like what you're contemplating and ended up with
some contamination problems in the second runoff batch. I like your
grain to water ratio, however.

Are you planning to do a PH test along the way?

Ken

Matt Schmidt wrote:
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>Is there a way to determine gravity of the sparge?
>My plan, & I will do this twice to collect the desired volumes.
>mash 12# grain with 3 gallon H20.
>Collect the first runnings in one bucket and then collect the sparge
>in a seperate bucket.
>I should then have approx 5 gallons of high grav and about 6 gallons
>low gravity liquor.
>
>how do I predict gravity / volume before and after boils?
>If I'm shooting for OG 1.05, and my 6 gallons are say 1.045, how much
>should I expect to collect in order to get 1.05.
>Are there formula for this?
>
>TIA
>
>~Matt
>
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