1/2/3 vessel convertible setup?

[wilserbrewer]

I also thought Bobby's #'s were optimistic, so I turned to my favorite rackers calculator, "Can I Mash it"

Well 20 lbs of grain at 2.6 qt/lb (13 gallon strike) yields 14.6 gallons.

Bobby's on the money...

 

[TexasWine]

I did the same and checked with my favorite, the priceless BIAB calculator. Looks like he assumes 0.079, which is in the ballpark of what Bobby said and also corroborates what I've heard, that the grain displaces about as much as it absorbs in a typical BIAB set up.

 

[BrunDog]

Fair enough. Any thoughts if that volume increases over time (e.g. grains swell and occupy more space)?

 

[TexasWine]

Fair enough. Any thoughts if that volume increases over time (e.g. grains swell and occupy more space)?

My hypothesis, it goes in the other direction. It seems that as all the nooks and crannies of the grain particles get filled with water, they would displace less of the water volume. It would be kind of like submerging an upside down beer bottle. If your turn it right side up and replace all that air with water, it takes up less room.

Just my thoughts. Maybe completely wrong.