Mash Thickness & Dead Space With RIMS - Home Brew Forums

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07-22-2012, 04:39 PM   #1
BFM

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When calculating grain to water ratio does the dead space matter? I have a false bottom which would have about 1.5 gallons of water under it, but I also have a dip tube. So all of the water will be recirculated back through the mash. Do I calculate 0 dead space?

07-22-2012, 04:43 PM   #2
MalFet
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It depends on what you're measuring and why. If you're trying to use one of the calculators, don't count it as deadspace because the assumption is that deadspace liquid isn't reclaimed at the end of mashing and sparging. If, on the other hand, you're trying to figure out your water/grist ratio to keep your mash consistently stiff, you do need to consider it.
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07-22-2012, 04:47 PM   #3
BFM

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That makes sense, thanks! This was going off of the beersmith mash profile screen. So I'll just set it to 1.50 qt/lb. that should give me a goof "buffer" and not calculate for dead space or maybe <.25 gallons..

07-22-2012, 04:55 PM   #4
MalFet
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Quote:
 Originally Posted by NervousDad That makes sense, thanks! This was going off of the beersmith mash profile screen. So I'll just set it to 1.50 qt/lb. that should give me a goof "buffer" and not calculate for dead space or maybe <.25 gallons..
Hmm...I'm not sure what BeerSmith does, but for calculating water volumes you definitely don't want to treat the volume under your false bottom as deadspace.

Water to grist ratios don't actually matter particularly much. Just make sure you've got enough water to submerge your grains properly, particularly with small beers.
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07-22-2012, 05:02 PM   #5
tjpfeister

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You need to include the volume of deadspace in your temperature calculations (strike or infusion), but not in your grain to water ratio.
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07-22-2012, 05:04 PM   #6
tjpfeister

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You need to include "dead space" in all of your temperature calculations, such as strike or infusion. You do no include dead space in your grain to water ratio however.
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