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Mash tun too small

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Blauwkonein

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I have a mash tun of 6.6 gallons and my recipe (batch sparge) consists of a 14 lbs grain bill, which with a ratio of 1.25/1 comes down to adding 17.50 qt of strike water and then sparging in two steps of 2.56 gal and 2.56 gal. I am afraid the strike water won't fit in my mash tun..

What are my options here? Lowering down to an 1/1 ratio? I have a second (6.6 gallon) cooler, so I also consider fly sparging. It is my first all-grain batch however, so I have no experience in that. Would fly sparging mean less water in the mash tun at a given time? If yes, how much?
 
Using the Green Bay Rackers "can I mash it?" calculator it seems like you'd only use 5.5 gallons of your mash tun at 1.25 qt per pound. Sounds like you're fine.

http://www.rackers.org/calcs.shtml

Yeah, that's what I got out of it as well. But when I filled up my mash tun with the grains to test, it was already quite full. How much water would actually fit in the grain bed? That is the main concern. Also, I don't understand how my Beersmith recipe comes out at 17,5 Qts strike water, which is already 4.3 gallons, and then the Rackers tells me I'm going to use 5.5 gallons in total. Maybe I am missing something here, as I am used to a metric system myself. But it does not make sense to me
 
Yeah, that's what I got out of it as well. But when I filled up my mash tun with the grains to test, it was already quite full. How much water would actually fit in the grain bed? That is the main concern. Also, I don't understand how my Beersmith recipe comes out at 17,5 Qts strike water, which is already 4.3 gallons, and then the Rackers tells me I'm going to use 5.5 gallons in total. Maybe I am missing something here, as I am used to a metric system myself. But it does not make sense to me

I don't think the Rackers calculator is accurate. I've measured the volume of 1lb of grain and it comes to 0.18 - 0.2 gallons per pound. 14lb x 0.18 = 2.52 gallons just for your grain.

Add the water to that @1.25qts / lb = 17.5qts = 4.38 gallons.

2.52 + 4.38 = 6.9 gallons needed.

Far off from the Rackers calculation.

My guess is your mash tun is too small unless you do a thicker mash.
 
beersmith is accurate. Just adjust your mash thickness until you get it to fit. You will be pushing the limits of your tun either way. consider sticking a little hotter adding 3/4 of your water then your grain do all your stirring while you have some space to work with then add the remaining 1/4 of your strike water otherwise you may find yourself making a huge mess trying to properly stir that mash.

I used a 5g mash tun for a handful of batches then I got tired of all the extra sparge steps and went to a 10g.
 
Yeah, that is exactly what I thought. Could I go 1/1 (in that case 2.52 + 3.5 = 6 gallons)? How exactly does this work, in which stage do you make up for the less water that you used to reach your pre boil volume? In the sparging, or?
 
Yeah, that is exactly what I thought. Could I go 1/1 (in that case 2.52 + 3.5 = 6 gallons)? How exactly does this work, in which stage do you make up for the less water that you used to reach your pre boil volume? In the sparging, or?

Yes, 1:1 would work.

Yes to your second question as well, you make up the wort volume when sparging.
 
Yeah, that's what I got out of it as well. But when I filled up my mash tun with the grains to test, it was already quite full. How much water would actually fit in the grain bed? That is the main concern. Also, I don't understand how my Beersmith recipe comes out at 17,5 Qts strike water, which is already 4.3 gallons, and then the Rackers tells me I'm going to use 5.5 gallons in total. Maybe I am missing something here, as I am used to a metric system myself. But it does not make sense to me

I don't think you're accounting for water absorption by the grain.

On the Beersmith forum Brad Smith states 1 pound of grain absorbs .12 gallons of water.
 
Yeah, that's what I got out of it as well. But when I filled up my mash tun with the grains to test, it was already quite full. How much water would actually fit in the grain bed? That is the main concern. Also, I don't understand how my Beersmith recipe comes out at 17,5 Qts strike water, which is already 4.3 gallons, and then the Rackers tells me I'm going to use 5.5 gallons in total. Maybe I am missing something here, as I am used to a metric system myself. But it does not make sense to me

I don't think you're accounting for water absorption by the grain.

On the Beersmith forum Brad Smith states that a pound of grain absorbs .12 gallons of water.
 
Do you already have the grains milled and mixed together? If not, there is another option available no one has mentioned yet that I have done before. You can simply reduce the amount of pale malt to get to a better ratio that will work for you. Then, once you are in the kettle, add some light DME or LME to get to the intended gravity. Just use your favorite recipe calculator to figure out how much DME or LME you need to add in the kettle.

Before I upgraded to a 10 gallon mash tun to replace my 5 gallon, I brewed a double IPA with this strategy. No shame in using some DME or LME if it still makes good beer!
 
Yeah, that's what I got out of it as well. But when I filled up my mash tun with the grains to test, it was already quite full. How much water would actually fit in the grain bed? That is the main concern. Also, I don't understand how my Beersmith recipe comes out at 17,5 Qts strike water, which is already 4.3 gallons, and then the Rackers tells me I'm going to use 5.5 gallons in total. Maybe I am missing something here, as I am used to a metric system myself. But it does not make sense to me

I don't think you're accounting for water absorption by the grain.

On the Beersmith forum Brad Smith states that a pound of grain absorbs .12 gallons of water.
 
beersmith is accurate. Just adjust your mash thickness until you get it to fit. You will be pushing the limits of your tun either way. consider sticking a little hotter adding 3/4 of your water then your grain do all your stirring while you have some space to work with then add the remaining 1/4 of your strike water otherwise you may find yourself making a huge mess trying to properly stir that mash.

I used a 5g mash tun for a handful of batches then I got tired of all the extra sparge steps and went to a 10g.

I'm gonna go for this method, as it's the only option right now. I live in Tbilisi, Georgia, so shipping DME from the US is too expensive. So is shipping a 10 gallon cooler ....

I will adjust my mash thickness to 1:1, meaning I mash in with 3.5 gallons, and add up the rest in the batch sparges (2x 3.0 gallons). In steps, I add 3/4 of the water (2.63 gallons), then add the grains, stir up, then add 1/4 of the water (0.87 gallons). Let it sit for 45 minutes according to the recipe, drain, (vorlauf?), batch sparge twice.

Two questions on this:
1. What do you mean with 'consider sticking a little hotter'? A higher strike water temperature (I'd mash at 153 F now)?
2. Should I vorlauf when draining?
 
Sorry that was a typo. I meant striking. Because you are mashing thinker the water will need to be hotter initially to heat the grains to your strike temp. Beersmith should figure that all out for you though if you adjust the ratio in the program.

I would vorlauf before I run into the kettle to set the bed and keep as much grain particulate out of my wort as I can. Some say this is unnecessary but I have always done it.
 
Why not just do a smaller batch? Doesn't have to be 5 gallons.

Three gallons of good beer beats five gallons of marginal beer because you pushed the limits of your system.

All the Best,
D. White
 
14 pounds of grain and 17.5 quarts of water will use 5.5 gallons worth of space in your cooler. The rackers calculator is accurate, and Beersmith gives me the same number. If it's indeed a 6.6 gallon cooler, you'll have plenty of space.

When you drain your first runnings, you'll have plenty of space to add your first 2.56 gallons of sparge water. After draining that, you'll have plenty of room for your second 2.56 gallon sparge.
 
Well, that's what I thought. The cooler was 25 liters as advertised (6,6 gal), but after throwing in the 14 lbs of grain, I think max 8-9 quarts of water fitted in there. I am kind of sure now that despite telling me this was a 25L cooler, it is probably not more than 18L (just under 5 gal). Welcome to Georgia :)))

I'll stick to smaller batches and build a mash tun out of a 50L keg in the meantime. Would it be a problem to do a 3 gallon batch in a 10 gallon brewing pot by the way? In terms of evaporation or so?
 
I'll stick to smaller batches and build a mash tun out of a 50L keg in the meantime. Would it be a problem to do a 3 gallon batch in a 10 gallon brewing pot by the way? In terms of evaporation or so?


I'd suggest a larger cooler over the keg, easier to maintain temps, jmo.

A 3 gallon batch in a 10 gallon pot is not a problem, just account for a bit more boil off.
 
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