This is how big your Mash Tun needs to be

[Denny]

also, does this chart/information factor in the volume dispersion of a false bottom or a manifold? i really would prefer a round cooler because i think it will hold temps better just based on the physics of it, BUT....a false bottom in a 10 gallon cooler will take up some room......is that accounted for in this chart?

I use a 48 qt. rectangular cooler. I make 5 gal. batches, usually with 12-17 lb. of grain. I lose maybe 1-2 F over an hour mash, so I don't think you need to wrry about losing heat.

 

[malvado78]

Larger opening. Easier to stir and clean.

Trade off is a higher amount of dead space though that can effect efficiency.

 

[Denny]

Trade off is a higher amount of dead space though that can effect efficiency.

You're gonna have to explain that one to me. I've used a rectangular cooler for 426 batches now. I have no dead space and on yesterday's brew got 86% efficiency onto the fermenter.

 

[mendozer]

Trade off is a higher amount of dead space though that can effect efficiency.

i use a 36 qt cooler to split 10 gallon batches with a friend. The other day i did my first 5 gallon in it. Terrible efficiency, in the 60s! Could be due to dead space AND/OR the fact that I was using Mesquite pods as some of the grains so my grain bed wasn't much of a sponge. It floated up with water as I was sparging. We'll see what a 5 gallon of only grains looks like

 

[fish2night]

70 Quart Cooler... going to probably just brew-up a 5 gallon batch... Is the cooler too big? Will I have a problem with the grain bed?

 

[SpottedDogBrewing]

I fit 85.5lbs of grain with almost 30 gallons of water in a 150qt cooler! The only problem with that is moving it and dumping it

 

[Denny]

70 Quart Cooler... going to probably just brew-up a 5 gallon batch... Is the cooler too big? Will I have a problem with the grain bed?

No problem if you batch sparge.

 

[najel]

No problem if you batch sparge.

So when batch sparging, all the stuff you read about the grain bed being at least so many inches and no more than so many inches does not matter?
I'm asking because I have a 48 qt rectangular cooler that is very clean that I could use to build a lauter tun, but I am afraid that it will be too large since I am only planning on 5 gallon batches with OGs in the 40s to 50s.

 

[Pie_Man]

So when batch sparging, all the stuff you read about the grain bed being at least so many inches and no more than so many inches does not matter?
I'm asking because I have a 48 qt rectangular cooler that is very clean that I could use to build a lauter tun, but I am afraid that it will be too large since I am only planning on 5 gallon batches with OGs in the 40s to 50s.

You shouldn't have an issue, many on this forum use that exact setup.

 

[najel]

Great, thanks! I guess I will get to work building that thing then.

 

[Denny]

So when batch sparging, all the stuff you read about the grain bed being at least so many inches and no more than so many inches does not matter?
I'm asking because I have a 48 qt rectangular cooler that is very clean that I could use to build a lauter tun, but I am afraid that it will be too large since I am only planning on 5 gallon batches with OGs in the 40s to 50s.

You are correct...the traditional advice about grain bed depth does not relate to batch sparging. I've made 426 5 gal. batches in a 48 qt. cooler over the last 14+ years. If it didn't work I would have switched to something else a long time ago!

 

[Radegast]

Great chart! What's the max size for a no-sparge batch relative to these max batch sizes?

 

[mendozer]

i've also noticed that fly sparging with only a 5 gallon batch is hard because of what little water is coming in from the top of my tun. I guess i'll have to just batch when i do 5s and fly when i do 10s

 

[BrewmeisterSmith]

I've been attempting to 10 gallon batches in a 10 gallon igloo cooler. For an IPA that I'm about to do, it calls for 28 lbs or grain. If I calculate my strike water at 1.25 qt per pound, I come up with 8.75 Gallons needed. That doesn’t leave much room in the tank for the grain. I did a brown ale recently and ran into the same thing. I just filled my cooler with strike water as much as I could. I felt the batch tasted a bit thin. I also batch sparge. So, filling up the mash tun doesn’t leave any room for the mashout either. Anyone run into this problem and have a solution? Looking at the chart, I may have to invest in a bigger mash tun.

 

[nutty_gnome]

I use a 5 gallon cooler and since life begins at 60 (1.060 that is!) I never have room for a traditional mashout. Instead I drain roughly 1.75 gallons of wort from the cooler and bring it to a boil then return it to the cooler. This raises the temp of everything to 168-170 depending upon the day and recipe. It absolutely loosens the grain bed. After 10 minutes I start draining and batch sparging.

 

[Denny]

I've been attempting to 10 gallon batches in a 10 gallon igloo cooler. For an IPA that I'm about to do, it calls for 28 lbs or grain. If I calculate my strike water at 1.25 qt per pound, I come up with 8.75 Gallons needed. That doesn’t leave much room in the tank for the grain. I did a brown ale recently and ran into the same thing. I just filled my cooler with strike water as much as I could. I felt the batch tasted a bit thin. I also batch sparge. So, filling up the mash tun doesn’t leave any room for the mashout either. Anyone run into this problem and have a solution? Looking at the chart, I may have to invest in a bigger mash tun.

Short of a bigger tun (highly recommended), you can just skip the mashout. No big deal.

 

[mendozer]

i've never done a mashout, just sparge. I also strike with 1.75 qt/lb if that matters

 

[GrogNerd]

looking at the 36qt Coleman Extreme 5 and it lists interior dimensions at 19.75 in. x 7.75 in. x 10 in.

= 1,530.625 cubic inches
/231 ≈ 6.6 gallons ≈ 26.5 quarts

I majored in math, so arithmetic is not my strong suit, and anyone correct me if I'm wrong, but 26.5 quarts ≠ 36 quarts

where did the other 2½ gallons go?

which makes striking a perfectly reasonable 6.75 gallons in what SHOULD BE a 36 quart system a little difficult

 

[Denny]

Probably the volume under the lid, which you can't use. My 48 qt. cooler really holds about 9.5 gal., not 12.

 

[GrogNerd]

I can get the 70 qt version for about the same price

12½ x 24½ x 10½ interior = 3215.625 in³ = 13.92 gal = 55.6 qt

that'll work just fine

 

[johns]

nice thread

 

[justkev52]

There seems to be a huge uprising in the number of new all grain brewers and the persistent question is "how big of a tun do I need?" It depends on what your batch size, efficiency, and desired OG is. Here's the easy way for you to decide based on your needs.

Keep in mind that even if you think you might want to do both 5 and 10 gallon batches, odds are your really high gravity beers will be 5 gallon batches. Who needs 10 gallons of barleywine?

Just for example, a 10 gallon mash tun can do 5 gallons of 1.118 barleywine (~11% ABV) and 10 gallon batches of 1.060 IPA (~6% ABV). I personally think something in the 50-60qt range is most flexible in that regard if you don't mind a square/rectangular cooler.

If you want to figure for larger or smaller batch sizes, take the number in the "Max Gravity Units" column and divide that by your desired batch size.

That's cool. Thanks for the chart. All good to know.

 

[davebstock]

Excellent thread here! If I didnt see this, I would have been screwed on my next brew!

 

[rodduley]

Can somebody tell me how much volume loss would occur if you cut the top of a 15.5 gallon keg off where the skirt meets. In other words there would be no curve, only straight sides. I'm guessing less than a gallon but wanted to be sure. I'm wanting to make a straight sided Mash Tun for a "tippy dump" and am trying to figure how much volume it would be.

Thanks

 

[wilserbrewer]

Well, I just eyeballed a 1/2 keg in my garage and I would estimate that cutting as you would describe would reduce the capacity comapared to a full uncut keg by approx 3 quarts, even less compared to a keggle cut at a 12" top hole as typically cut. To get a better number would take filling it and measuring the water level to the skirt weld, then using a measured pitcher fill the remaining volume.

 

[helibrewer]

Just figure your strike water based on your ratio. Take your grain weight and multiply by 0.1 to get your "gallons" equivalent from the grain....add the two together and that's how big your MLT needs to be.

15 pounds at 1.5 qts per pound = 5.6 gallons strike plus 1.5 "gallons" of grain = 7.1 gallon MLT requirement.

 

[fc36]

Just figure your strike water based on your ratio. Take your grain weight and multiply by 0.1 to get your "gallons" equivalent from the grain....add the two together and that's how big your MLT needs to be.

15 pounds at 1.5 qts per pound = 5.6 gallons strike plus 1.5 "gallons" of grain = 7.1 gallon MLT requirement.

Couldn't have said it any better!

 

[SpeedYellow]

looking at the 36qt Coleman Extreme 5 and it lists interior dimensions at 19.75 in. x 7.75 in. x 10 in.

= 1,530.625 cubic inches
/231 ≈ 6.6 gallons ≈ 26.5 quarts

I majored in math, so arithmetic is not my strong suit, and anyone correct me if I'm wrong, but 26.5 quarts ≠ 36 quarts

where did the other 2½ gallons go?

which makes striking a perfectly reasonable 6.75 gallons in what SHOULD BE a 36 quart system a little difficult

FWIW, their measurements are off. I measured my 36-qt Coleman Extreme and it's about 8.0-8.2 gal (32-33 qt).

Just figure your strike water based on your ratio. Take your grain weight and multiply by 0.1 to get your "gallons" equivalent from the grain....add the two together and that's how big your MLT needs to be.

15 pounds at 1.5 qts per pound = 5.6 gallons strike plus 1.5 "gallons" of grain = 7.1 gallon MLT requirement.

Awesome way to boil this down!! :rockin: Seems to be a smidgen optimistic but perhaps that's just my measurements.

 

[Denny]

Cooler manufacturers usually include the volume of the concave space under the lid as part of the total volume. Obviously we can't use that for mashing.

 

[juggabrew]

Ok trying to understand, I'm new so if I'm only doing 5 gal batches no bigger than 1.090 I would need a 36 qt cooler

(90x5)/17=26.5 qt minimum tun

Is this correct? I want to have the option of both batch and fly sparging, does this play into it?