BIAB calculator challenged......

[gizmodog51]

i have taken the grain wt and hop schedule, mash in temps and boil volume & boil time from the sticky tutorial on BIAB brewing and used them with the BIAB calculator but i do not arrive at the 7.5 gallons of water as @ the tutorial recipes states.
the biab calculator shows me water volume 9.91
strike temp 152,47 for a 154 mash?
post boil volume 7.07 gallons not the 5.5 as @ recipe.

can some one tell me what i'm doing wrong?

thanx
GD51

 

[acidrain]

There are several calculators... which one are you using (link please)?

 

[weirdboy]

How many pounds of grain in the recipe?


If you are using beersmith as your calculator, you should know up-front that it gets that stuff all wrong.

 

[gizmodog51]

There are several calculators... which one are you using (link please)?

thanx for the reply........this is the link:http://www.simplebiabcalculator.com/

GD51

 

[gizmodog51]

How many pounds of grain in the recipe?


If you are using beersmith as your calculator, you should know up-front that it gets that stuff all wrong.

this is from the sticky in the all grain /partial mash topic line :

Modified Recipe
--------------------------
Recipe Type: All Grain
Yeast: Irish Ale (Wyeast Labs #1084)
Yeast Starter: Yes
Batch Size: 5.50 gal
Boil Size: 7.50 gal
Estimated OG: 1.056 SG
Estimated Color: 34.2 SRM
Estimated IBU: 16.3 IBU
Brewhouse Efficiency: 70.00 %
Boil Time: 60 Minutes
Mash In: 60 Minutes with 7.50 gal of water @ 159.3 F
Mash Out: 10 Minutes with 0.00 gal of water at 170.0 F

Ingredients:
---------------
9.00 lb Pale Malt (2 Row) US (2.0 SRM)
1.00 lb Barley, Flaked (1.7 SRM) Grain
1.00 lb Roasted Barley (300.0 SRM) Grain
0.75 lb Caramel/Crystal Malt - 20L Grain
0.50 lb Caramel/Crystal Malt - 40L Grain
0.50 lb Chocolate Malt (350.0 SRM) Grain
0.70 oz Cluster (60 min) Hops
1.00 oz Goldings, East Kent (10 min) Hops
0.25 oz Williamette (2 min) Hops
8.00 oz Cocoa Powder (Boil 5.0 min) (pre-mixed with hot water)
1 Pkgs Irish Ale (Wyeast Labs #1084) Yeast

Total Grain Weight: 12.75 lbs


GD51

 

[weirdboy]

OK well the grain is going to absorb about 1.25 gallons of water (actually a bit more), assuming you squeeze the bag pretty well and collect the runoff. So that means you need at a bare minimum:

5.5 (batch size) +
1.25 (losses to grain absorption) +
1.0 or more (boil-off)
----
7.75 gallons, assuming you have absolutely no trub losses (fat chance) and boil off water at exactly 1 gallon per hour...that really depends on your particular system.

On my system (which does boil-off pretty close to 1 gallon per hour), I would use more like 8.25 gallons to account for trub losses, a bit of spillage, and the wort that remains in the hoses & chiller after transferring to the fermenter.

I usually just sort of estimate my strike water temp, but I would probably heat the strike water to about 157F or so and stir in the grain. You may end up a bit low or a bit high, but it is pretty easy to make small temperature adjustments in BIAB, which is why I don't worry about dialing it in too accurately.

 

[acidrain]

I entered all your info into the calculator and got 7.91 gallons, 161.85 strike temp, for a 5.25 gallon batch.

 

[RM-MN]

Dang, I've been doing this BIAB thing all wrong. I just made two batches with about 11 pounds of grain each using full volume for mashing and managed to fit it all into my 7 1/2 gallon pot. By the end of the boil I had about 5.25 gallons of wort. Now explain to me how I fit the 9.91 gallons (shown in the OP's first post) or even the 7.91 gallons shown in post #7 into my 7 1/2 gallon pot.

 

[william_shakes_beer]

I use Tasty brew for all my calculations and have always been accurate. (strike temp, mash volume, etc) If you are geting bad numbers, perhaps its time to build your own spreadsheet. That's what I did. Not because I mistrust the online calculators but because my brain needs to process the raw data and understand where they are coming from. The math is not complicated, and I believe it makes me a more intuitive brewer.

 

[divrguy]

How many pounds of grain in the recipe?

If you are using beersmith as your calculator, you should know up-front that it gets that stuff all wrong.

Not really... You have to set up Beersmith correctly for BIAB. It takes some testing for your equipment but the Beersmith website shows you how to dial it in.

Dang, I've been doing this BIAB thing all wrong. I just made two batches with about 11 pounds of grain each using full volume for mashing and managed to fit it all into my 7 1/2 gallon pot. By the end of the boil I had about 5.25 gallons of wort. Now explain to me how I fit the 9.91 gallons (shown in the OP's first post) or even the 7.91 gallons shown in post #7 into my 7 1/2 gallon pot.

There are more than a few ways to BIAB but if you really want to true BIAB, you need to add all of your water up front. Which means my 8 gallon pot doesn't usually work for a full 5 gallon brew with a sizeable grain bill. But, you can easily modify it by using a couple of kettles and sparging, doing sort of a partial boil or tossing in a bit of DME or LME to make up the difference so you can use your 7.5 gallon pot. I also scale some of my recipes down a bit to a 4 gallon just so I can use a smaller pot. But that means less beer... But in my case, I also do 1-2 and 3 gallon batches so I can have a variety.

 

[weirdboy]

Dang, I've been doing this BIAB thing all wrong. I just made two batches with about 11 pounds of grain each using full volume for mashing and managed to fit it all into my 7 1/2 gallon pot. By the end of the boil I had about 5.25 gallons of wort. Now explain to me how I fit the 9.91 gallons (shown in the OP's first post) or even the 7.91 gallons shown in post #7 into my 7 1/2 gallon pot.

You have a different boil-off rate and I'm willing to bet you don't leave a quart or more of trub sitting in the bottom of the kettle.

 

[weirdboy]

Not really... You have to set up Beersmith correctly for BIAB. It takes some testing for your equipment but the Beersmith website shows you how to dial it in.

Let me rephrase that...I previously did BIAB in Beersmith v1 and never had a problem with it. Then I upgrade, and did mostly stuff with a separate MLT until late last year, at which time I went back to BIAB. So, I select BIAB equipment for my equipment, I select BIAB mash profile for my mash, and all of the numbers that it gave me on the brewsheet were wrong. It was coming up with impossible numbers. e.g. I set my target batch size to 5.25 gallons, and it tells me I should have 7 gallons post boil.

I was able to get it closer by a lot of tweaks to the default equipment profiles, but it still have weird numbers coming out for some of the volumes. So I ended up making my own spreadsheet and nowadays I stick by that because I know it works well for my system. Brad may have then subsequently gone back and released a new version that addressed these issues, but out of the box it was worse than useless; it actually gave people incorrect instructions.

 

[divrguy]

Let me rephrase that...I previously did BIAB in Beersmith v1 and never had a problem with it. Then I upgrade, and did mostly stuff with a separate MLT until late last year, at which time I went back to BIAB. So, I select BIAB equipment for my equipment, I select BIAB mash profile for my mash, and all of the numbers that it gave me on the brewsheet were wrong. It was coming up with impossible numbers. e.g. I set my target batch size to 5.25 gallons, and it tells me I should have 7 gallons post boil.

I was able to get it closer by a lot of tweaks to the default equipment profiles, but it still have weird numbers coming out for some of the volumes. So I ended up making my own spreadsheet and nowadays I stick by that because I know it works well for my system. Brad may have then subsequently gone back and released a new version that addressed these issues, but out of the box it was worse than useless; it actually gave people incorrect instructions.

Dude... I totally believe you. When I first started doing BIAB, Beersmith was so far off I couldn't believe it. I had to read like 10 posts from guys who were experiencing issues. Originally, I just used a BIAB spreadsheet. But, after some tweaks, reading, tweaking and so on. I finally figured out my profile for all of the different batch sizes and equipment profiles and it works. There's also a grain absorption number in there I had to set because I had to kind of match it to how much I squeezed. I do remember it being a total PITA and don't even know if I could replicate it easily with a new pot. But it is possible. Now it gets me to within less than a quart on a big batch and a few ounces on a smaller one. Good luck with yours!

 

[gizmodog51]

OK well the grain is going to absorb about 1.25 gallons of water (actually a bit more), assuming you squeeze the bag pretty well and collect the runoff. So that means you need at a bare minimum:

5.5 (batch size) +
1.25 (losses to grain absorption) +
1.0 or more (boil-off)
----
7.75 gallons, assuming you have absolutely no trub losses (fat chance) and boil off water at exactly 1 gallon per hour...that really depends on your particular system.

On my system (which does boil-off pretty close to 1 gallon per hour), I would use more like 8.25 gallons to account for trub losses, a bit of spillage, and the wort that remains in the hoses & chiller after transferring to the fermenter.

I usually just sort of estimate my strike water temp, but I would probably heat the strike water to about 157F or so and stir in the grain. You may end up a bit low or a bit high, but it is pretty easy to make small temperature adjustments in BIAB, which is why I don't worry about dialing it in too accurately.

thanx for the reply......
are there any forumlas to determine grain absorption per lb?
i have not seen this kind of info in the dave miller book that i used to learn with.
i'll research this i'm sure the formulas can be found....and i imagine I'm probably being too anal over all this since BIAB is supposed to be simplicity.

aprreciate everyones replys......

GD51

 

[gizmodog51]

I entered all your info into the calculator and got 7.91 gallons, 161.85 strike temp, for a 5.25 gallon batch.

i found this today on the internet...i know it's not for BIAB but i think it will help me to understand whats happening and how to calculate for the water losts.

http://www.brew365.com/technique_calculating_mash_water_volume.php

GD51

 

[weirdboy]

thanx for the reply......
are there any forumlas to determine grain absorption per lb?
i have not seen this kind of info in the dave miller book that i used to learn with.
i'll research this i'm sure the formulas can be found....and i imagine I'm probably being too anal over all this since BIAB is supposed to be simplicity.

aprreciate everyones replys......

GD51

For BIAB the grain absorption rate can vary depending on how your system works, how much you squeeze the bag, etc.

For my system I use .10 gallon/lb. and get pretty close. I have seen figures as low as .05 gallon/lb thrown around before, but to me that seems like you'd have to do an awful lot of work to get that much liquid back out. I'm lazy.

 

[acidrain]

Dang, I've been doing this BIAB thing all wrong. I just made two batches with about 11 pounds of grain each using full volume for mashing and managed to fit it all into my 7 1/2 gallon pot. By the end of the boil I had about 5.25 gallons of wort. Now explain to me how I fit the 9.91 gallons (shown in the OP's first post) or even the 7.91 gallons shown in post #7 into my 7 1/2 gallon pot.

Because 11 lbs. is not 12.75 lbs.
My BIAB brews are typically in the 13 lb range, and the full volume water that my system needs does not fit in my 8 gallon kettle, which means I go to my 15 gallon kettle, which means my boil off rate is much higher, which means I need even more water.
Every bodies system is different, so no, it doesn't mean you're doing it wrong, it just means your system is different.

 

[ThePonchoKid]

I'm willing to bet you don't leave a quart or more of trub sitting in the bottom of the kettle.

I leave probably a half quart, 3/4 tops. It's hard to separate the clear stuff from the muck, unless I were carefully siphoning off the wort in to my primary

 

[beernut70]

After a couple of batches I came to use about .11 Gal/lb so that seems to be a pretty consistent absorption ratio. Here is a pretty nice and simple excel calculator it even gives you your mash volume. For the trub in the kettle I just dump it all in unless I used a huge amount of hops.

http://www.homebrewfinds.com/2012/03/start-all-grain-brewing-for-4-water.html

 

[MMJfan]

There are more than a few ways to BIAB but if you really want to true BIAB, you need to add all of your water up front. Which means my 8 gallon pot doesn't usually work for a full 5 gallon brew with a sizeable grain bill. But, you can easily modify it by using a couple of kettles and sparging, doing sort of a partial boil or tossing in a bit of DME or LME to make up the difference so you can use your 7.5 gallon pot. I also scale some of my recipes down a bit to a 4 gallon just so I can use a smaller pot. But that means less beer... But in my case, I also do 1-2 and 3 gallon batches so I can have a variety.

This is what I've found to work best for me. I too only have a 7.5 gallon kettle and I like my 5 gallon batches. So what I do is, using a full grain bill from whatever recipe I'm using, mash the grains in about 6 gallons of water in my 7.5 gallon kettle. I then have a 5 gallon kettle that I will fill with about 2.5 gallons of water and sparge the grain bag in there at about 170 degrees. I then combine the two liquids into my 7.5 gallon kettle for the boil. I've been getting between 75 and 80 on my efficiencies so far btw...