How do you BIAB with a smaller pot?

[losman26]

Normally I use a 15 gal pot for BIAB, which isn't a problem, but just installed a valve on my 20 quart pot, and am going to do a 2.5 gal batch. According to the BIAB calc, I'm supposed to put 4 gal of water for the mash. I'm thinking that there's no way this is gonna work with this pot without creating a huge mess.

Should I perhaps mash with 3 gal, and then sparge later with 1 gal? Would that be a good way to compensate?

[teutonic terror]

I have also done 2.5 gallon batches in a five gallon kettle.
What I usually do is mash with 1.25 qts per pound of grain.
I then do two dunk sparges at 168F in a bucket for 10 minutes. I will then rinse, if need be to reach boil volume!
I also squeeze the bag in between each sparge.

[Brewbirds]

We use two pots, mashing in one and dunk sparging in the other. Since we also have to top off it's a true BIAB but it works quite well now that we got dialed in.

[losman26]

We use two pots, mashing in one and dunk sparging in the other. Since we also have to top off it's a true BIAB but it works quite well now that we got dialed in.

So should I use 3 gals for the mashing, and then one gallon for the dunk sparging? How does it work? How do you calculate how much you put into each vessel?

[losman26]

I have also done 2.5 gallon batches in a five gallon kettle.
What I usually do is mash with 1.25 qts per pound of grain.
I then do two dunk sparges at 168F in a bucket for 10 minutes. I will then rinse, if need be to reach boil volume!
I also squeeze the bag in between each sparge.

That seems like a small amount of water when you compare it to all of the calculators out there.
I have 7 lbs of grain, so I'd only use 8.75 quarts for the mash? Seems about 1/2 of the water these calcs are telling me to do. I'm also doing a 90 min boil on this batch.

[joechianti]

No problem at all. I use a 16 qt pot for 2.5 gallon BIAB and it works fine. There's far more than one way to skin a cat, and whatever works for you is fine. I mash in about 2 gallons or so of water, then sparge with about a gallon, then do my hop boil. Works just fine every time.

[teutonic terror]

Just checked my last regular AG recipe in BrewSmith.
That is a traditional mash volume, just like using a mash tun.
I picked this method up from somewhere on the Mr Beer website or the Net, not sure where.
I think it was a BIAB website from Australia.
It was the only choice I had using an undersized kettle.
I have also done 5 gal batches in a 7.5 gal pot using this same method. Close to boil over on the boil, but doable!
I think what is most important is to know your boil off rate! Then you can figure your sparge and rinse amounts accordingly!

[Brewbirds]

BB2 says you shouldn't have to change your recipe if you are worried about head room. Grain displaces approx. .652 liters per kilogram so for your 7lbs of grain that is about 1/2 gallon. When you remove the grain bag you will loose approx 1 fluid ounce per ounce of grain. So you should have 7 1/2 quarts of headroom for your boil.

We can do a 7 lb BIAB in 2 quart pots which is actually less than 16 quarts from a space standpoint.

[philm00x]

If you have a fear about doing a full volume mash with a smaller pot, just use less water and then top off the fermenter when you're done w/ the boil. I usually use a water-to-grain ratio of 1.5 qt/lb like a regular mash and then squeeze the grain bag. When using a high amount of grain, I'll calculate on BeerSmith to have to add 1 gallon of water to the fermenter after the mash and boil, so that you do a partial volume mash. I have a 3 gallon pot and have done full volume mashes in it, but going up near the brim of the pot at the start of the boil. Keep a spray bottle of water handy to tame the hot break.

[losman26]

If you have a fear about doing a full volume mash with a smaller pot, just use less water and then top off the fermenter when you're done w/ the boil. I usually use a water-to-grain ratio of 1.5 qt/lb like a regular mash and then squeeze the grain bag. When using a high amount of grain, I'll calculate on BeerSmith to have to add 1 gallon of water to the fermenter after the mash and boil, so that you do a partial volume mash. I have a 3 gallon pot and have done full volume mashes in it, but going up near the brim of the pot at the start of the boil. Keep a spray bottle of water handy to tame the hot break.

The problem isn't the boil, it's the mash. I feel that once I put the grains in, it will over flow.

[Rebel_B]

Depends on the amount of grain, but I'll typically mash in with +/- 2-1/2 gallons of water, then sparging with 2 gallons; then a 90 minute boil...

[philm00x]

I guess it's one of those things that I've been taking advantage of BeerSmith to keep me from worrying about overflow when you put the grains in. It calculates how much mash water I need with a given water-to-grain ratio, and if it ends up being way too close to the capacity of my pot, then I'll make it so that I have to add a gallon to the fermenter after the boil so that I'm using less water in the mash and don't have to worry about the pot overflowing in the mash, or consequently the boil.

[mashani]

Reading this thread might help... lots of us do it in varying methods, all of which work.

viewtopic.php?f=13&t=210

EDIT: This might be useful too:

viewtopic.php?f=13&t=611

[losman26]

I ended up doing 3.5 gallons with the mash, and sparging. I took the wort and sparged the bag with the wort in my 15 gal pot. I then transfered to my 5 gal pot and sparged with one gallon. After some squeezing, I over shot my boil gravity by 10 pts, and had to add water to the boil. In the end, my SG before adding the yeast came out EXACTLY right, so I'm happy. I'm guessing that I will do sparging from now on, as it dramatically increases the efficiency. I'm guessing I hit at least 75%. Before this, I was in the low 60's.

[Foothiller]

For BIAB with up to 5 lb of grain in a 2-gallon cylindrical cooler, by moving the grain bag to a 2-gallon pot, draining the cooler into my 3-gallon boil pot, and sparging between two 2-gallon pots until I have my full boil volume. My weizenbock used 7 lb of grain, so I used that technique for 5 lb and mashed the other 2 lb in a 2-gallon pot and used a large strainer to drain it into the boil pot, as if it were a partial mash. A key is to use 1 to 1.5 quarts of mash water per lb of grain, however you can get to fit.