OG/FG all grain calculator discrepencies

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When estimating an all grain recipe with the OG/FC Calcutator then in puting in a new recipe the preboil -post boil and abv do not match. In fact the recipe is always ten to fifteen points higher. Why is this?
 
When estimating an all grain recipe with the OG/FC Calcutator then in puting in a new recipe the preboil -post boil and abv do not match. In fact the recipe is always ten to fifteen points higher. Why is this?

I don’t know what you mean- can you give me a link or a screenshot so I can see what’s going on?
 
Check that your pre-boil and post-boil sizes are correct in the recipe editor . i have a similar issue whenever i scale a receipe down to a smaller batch size, BF does not change the post boil size and it throws off the OG prediction. I have to change the post boil size manually to fix it.
 
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Check that your pre-boil and post-boil sizes are correct in the recipe editor . i have a similar issue whenever i scale a receipe down to a smaller batch size, BF does not change the post boil size and it throws off the OG prediction. I have to change the post boil size manually to fix it.
It's not the recipe editor . When I brewed the recipe it's fg was within 1 point. Somehow the og/fg calculator is at fault.
 
I don’t know what you mean- can you give me a link or a screenshot so I can see what’s going on?
Screenshot_20210728-132401_Opera.jpg
Screenshot_20210728-132144_Opera.jpg
 
Check that the batch sizes, start and finish are the same in both the calculator and the recipe editor, and the efficiency is the same. using the calculator tool with 5gal batch size/75% efficiency i get .037og post boil and 3.5%abv with a medium attenuation yeast
when i put that into the recipe builder-its .039OG, finishes at 3.8%, so pretty close.
 
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There's a couple reasons the standalone calculators may be slightly different, but overall the recipe builder is the recommended app. The calculators make several simplifications to various degrees, so they may not be as accurate or reliable as the full recipe builder.

For more specifics though we really do need a link to the full recipe, and all of the data you've entered into the calculator. Just the little snapshot included isn't sufficient.
 
I used the full recipe builder. It was way off! My OG was predicted at 1.056. It came in at 1.071.The app is useless.
When checked against a commercial breweries recipe which was 1.058 OG, the Brewer’s Friend Recipe Builder showed 1.048.
What accounts for this major flaw in the program?
 
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I used the full recipe builder. It was way off! My OG was predicted at 1.056. It came in at 1.071.The app is useless.
When checked against a commercial breweries recipe which was 1.058 OG, the Brewer’s Friend Recipe Builder showed 1.048.
What accounts for this major flaw in the program?
A lot depends on accurate inputs and settings. Please make your recipe public and provide a link to it, thanks.
 
I used the full recipe builder. It was way off! My OG was predicted at 1.056. It came in at 1.071.The app is useless.
When checked against a commercial breweries recipe which was 1.058 OG, the Brewer’s Friend Recipe Builder showed 1.048.
What accounts for this major flaw in the program?

1.058 for 24 pounds of grain in 10.5 gallons finished wort seems about right if your efficiency is 70%. You got 1.071?
 
Ok, thanks. I am guessing you use a conventional 3-pot brewing setup for 10 gallon batches, with recirculation and a fly sparge, or do I have this wrong?

Three 15.5 gallon stainless kettles. Continuous recirc of the mash. Sparge is gravity feed.
 
Three 15.5 gallon stainless kettles. Continuous recirc of the mash. Sparge is gravity feed.
Nice. Is it possible your brewhouse efficiency is greater than 70%? A friend with a similar system regularly exceeds 80%. Try fiddling with the brewhouse efficiency number until you see a 1.071 OG, could your efficiency possibly be that high?

Not saying it is, but truly wondering. My brewzilla regularly delivers 78%. At least, when I use 78 in my recipes it comes out very close.
 
I used the full recipe builder. It was way off! My OG was predicted at 1.056. It came in at 1.071.The app is useless.
When checked against a commercial breweries recipe which was 1.058 OG, the Brewer’s Friend Recipe Builder showed 1.048.
What accounts for this major flaw in the program?

The first problem is easy to solve: Brewer's Friend also shows an OG of 1.058. It's the pre-boil gravity that is 1.048.
upload_2021-9-15_20-21-46.png


For the higher than expected actual OG...just guessing here: Could the Wort Correction Factor be off? Maybe greater boiloff? Awesome efficiency? All of the above?
 
The first problem is easy to solve: Brewer's Friend also shows an OG of 1.058. It's the pre-boil gravity that is 1.048.
View attachment 17423

For the higher than expected actual OG...just guessing here: Could the Wort Correction Factor be off? Maybe greater boiloff? Awesome efficiency? All of the above?

That 1.048 number came from a commercial recipe that I plugged in for comparison. The beer came in at 1.058.
I do triple step infusion mashes - 122 for 30 minutes, 146 for 20 minutes, and 158 for 20 minutes. Mash out at 170.
Maybe this allows greater efficiency?
Or maybe I misread the refractometer? Unlikely, however.
 
After adjusting the efficiency to 90%, the predicted OG was 1.071.
Perhaps my system is more efficient than we thought.
 
After adjusting the efficiency to 90%, the predicted OG was 1.071.
Perhaps my system is more efficient than we thought.
Perhaps, but perhaps not. I would certainly think it is higher than 70 though.

For that commercial recipe, it would satisfy my curiosity to see what I got if I actually brewed it.

I guess my point is that, at least for me, the recipe builder* has been pretty close for me in well over a dozen recipes.

*Ha! Once I came to understand it!!
 

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