MLT shape pros/cons

[ToastedPenguin]

Progressing towards AG brewing from partial extract brewing. I have seen several howto's for constructing an MLT using an insulated cooler and while I have seen both rectangular and round MLT used, most indicate the decision for the shape was based on availability/price of the cooler.

Are there any particular reasons for using a rectangular cooler vs a round cooler when building an MLT that I should be aware of? Off the shelf sparge arms seem to be constructed for a round MLT but building a sparge arm or doing batch sparging with a rectangular cooler seems to level that field.

Looking for issues or gotchas that may exist for either option, or even the whole cooler option for that matter.

Thanks,
David

 

[TheMan]

I don't believe there are any drawbacks of either. As you stated, price affected my choice. My grandfather had a free rectangle cooler...A buddy of mine has used both rectangle and round, I've not seen any real difference in his brewing nor heard him say one was better than the other.

 

[bassbone]

Price affected my choice, too.

The only difference really is that premade MLT stuff (Sparge arm, false bottom, etc) are made for the round cooler sizes. I went with a 48qt igloo and built a CPVC false bottom b/c it was VERY cheap (about $30 total vs $50 for just the round cooler) and had more capacity than any round cooler I've seen.

 

[jaythebassist]

It can make a difference in grainbed depth. Usually this isn't an issue with any shape 40-50 qt cooler, even with a lower gravity beer @ 5g. But if you buy a 96qt rectangular cooler, then you're gonna have one thin-ass bed while brewing any avg beer for 5g batch.

Straight outta Palmer's How To Brew:

The shape of the cooler is only important in that it determines the grainbed depth. It is important to have a minimum grainbed depth of at least 4 inches. The optimum depth at this scale is probably about 1 foot. If it is too shallow, it won't clear sufficiently; too deep and it will tend to get stuck. A five gallon round cylindrical Gott cooler works well for 5 gallon batches; it can hold 12 pounds of grain and the water to mash it. Naturally, the 10 gallon size is good for doing 10 gallon batches. These coolers have convenient spigots which can be removed to make it easy to drain the wort.

 

[ToastedPenguin]

It can make a difference in grainbed depth. Usually this isn't an issue with any shape 40-50 qt cooler, even with a lower gravity beer @ 5g. But if you buy a 96qt rectangular cooler, then you're gonna have one thin-ass bed while brewing any avg beer for 5g batch.

Straight outta Palmer's How To Brew:

So the real consideration then becomes which MLT shape/size can maintain a minimum of 4 inches, optimally 1ft for the boil/wort volume that is going to be retrieved. So an MLT that might do well with 10G volumes probably won't work for a 5G volume. This suggests that I may end up with my first MLT being for 5G volumes and if and when I go to 10G batches I will need to get a new MLT.

David

 

[TheMan]

If you get a 10 gallon cooler it will work well for most brews. And I would suggest it. If you like to do big beers anything less would be tough to make work. Mine is 7.5 Gallons and the most I can mash is 16 #'s. Most around here would advocate 10 gallons as the most useable.

 

[devilishprune]

Most of the time when I brew my grainbed is less than 4 inches and I haven't found issue with this yet.

 

[maida7]

It depends on how you sparge. With fly sparging the bed depth is very important. More depth the better. So tall narrow coolers tend to work better.

With batch sparging, bed depth is not a real concern. Any shape cooler will work well with batch sparging.

 

[jaythebassist]

If you get a 10 gallon cooler it will work well for most brews. And I would suggest it. If you like to do big beers anything less would be tough to make work. Mine is 7.5 Gallons and the most I can mash is 16 #'s. Most around here would advocate 10 gallons as the most useable.

+1

a 40-52qt cooler will work well for anything you'd want to make in a 5g batch. If you get a 20qt cooler, you'll just be upgrading when you decided to make that 1.080 beer. Not if, but when.

It depends on how you sparge. With fly sparging the bed depth is very important. More depth the better. So tall narrow coolers tend to work better.

With batch sparging, bed depth is not a real concern. Any shape cooler will work well with batch sparging.

+1

 

[ToastedPenguin]

+1

a 40-52qt cooler will work well for anything you'd want to make in a 5g batch. If you get a 20qt cooler, you'll just be upgrading when you decided to make that 1.080 beer. Not if, but when.



+1

Sounds like I will be going after one of those coleman extreme 52qt coolers.....thanks for the advice.

 

[Bobby_M]

It depends on how you sparge. With fly sparging the bed depth is very important. More depth the better. So tall narrow coolers tend to work better.

With batch sparging, bed depth is not a real concern. Any shape cooler will work well with batch sparging.

True. Palmer pretty consistently forgets to differentiate between fly/batch sparging when discussing tun design, etc.

The one minuscule consideration of grainbed depth with batch sparging is that a really deep bed would be harder to stir. Also, if you've got a monster rectangular cooler and you're going for a low gravity 5 gallon batch, it would be a good idea to prop a 2x4 under the side opposite the drain. It will take some of the "quasi dead space" out of the equation. I say "quasi" because even if your cooler will fully drain water during a dead space test, a large flat bottom cooler will actually retain extra wort while you're mashing. Tilting the cooler let's gravity work for you.

 

[maida7]

Sounds like I will be going after one of those coleman extreme 52qt coolers.....thanks for the advice.

If your doing 5 gallon batches I think that cooler will only work well with batch sparge.

Does anybody use this cooler and do a fly sparge?

 

[v2comp]

I use a 5 gallon igloo cooler with the simple stainless braid for 5 gallon batches because it was first mash tun and I still have it. I fly sparge with it and can easily do a 1.065 ish beer with a little preparation.
I have a rectangular coleman extreme with a drilled copper manifold for doing 10 gallon batches and big (1.070 and up) 5 gallon batches.
I fly sparge with both systems and consistently achieve +/- 80% effeciency and could hardly be happier. if I only were going to have (1) mash tun, I would probably go with a round 10 gallon igloo cooler with the braid. its simple, fairly inexpensive overall and will make all but the highest gravity brews you are likely to make.
this whole mash tun debate is highly contentious because many people dont like to admit when they are: just getting started and havent brewed enough, not a disciplined brewer, dont pay enough attention to the details, only want to relax and have a homebrew, or a mixture of the above! the truth is that most of us will make great beer if we just slow down and follow our procedures consistently. the mash tuns sizes and shapes are important, but not so important that they will ruin the experience unless the rest of your brewing regimen isnt set up correctly.
fresh ingredients, good grain crush, water quality, temperatures, mash PH and sparge water temps will go a long way towards creating a great fermentable wort. if you slack on any of those, you will still make good beer, but not what many of us strive for.

 

[jim81147]

Which cooler is the best insulated ? i have a 48 Igloo but I have to keep a water heater blanket around it to keep my temps fairly constant. I would sure like to find a cooler that i did not have to use any blankets. The fact that I brew mostly in the winter does not help matters any.

 

[ToastedPenguin]

Which cooler is the best insulated ? i have a 48 Igloo but I have to keep a water heater blanket around it to keep my temps fairly constant. I would sure like to find a cooler that i did not have to use any blankets. The fact that I brew mostly in the winter does not help matters any.

I obviously haven't mashed yet, but my target MLT is a coleman extreme cooler, probably a 48-52qt version. I have been using one of the 72qt ones for camping and it does keep stuff ice cold for days in the heat of summer. I think it will do the same for keeping in the heat and I have seen several people using this cooler for a MLT.

David

 

[maida7]

Which cooler is the best insulated ? i have a 48 Igloo but I have to keep a water heater blanket around it to keep my temps fairly constant. I would sure like to find a cooler that i did not have to use any blankets. The fact that I brew mostly in the winter does not help matters any.

In my experience, heat loss in a cooler is because the cooler is absorbing the heat. If you pre-heat the cooler properly you can eliminate this problem.

I'm gonna guess that your Igloo 48 is just as good as any other cooler. So no real reason to change.

The only coolers I have seen that are substantially better insulated are the green colored Coleman extreme 6 series. The green ones have much thicker walls. The blue Coleman extreme 5 series are regular walls. Perhaps some other brands also have thick walled coolers. I've only looked at the colemans.

 

[v2comp]

+ 1 on if you preheat you shouldnt lose much heat at all in an hour long mash. if your outside in the winter, you might have to insulate whatever cooler you use.

 

[sweet_corn]

I use a rubbermaid 10 gallon rectangular, with a batch sparge. I brew all winter in Wisconsin. it was the cheapest when I bought it. I have never lost more that 3 degrees during an hours mash. I preheat with 1 gallon of boiling water. I think the amount of heat loss is over exaggerated in most cases.