Not hitting target OG with new equipment profile

[Gixxer]

I recently went to a false bottom. I have adjusted the tun deadspace numbers to account for the deadspace in BS... I physically measured this before using the false bottom. so when I create a recipe, just for starters to get a feel for how my numbers would look, I lowered my efficiency by 5%. Even after doing that and ensuring I had the correct number in there for tun deaddpace, all of my batches have been 5 points low OG on smaller beers, and 10 points low on big beers. Even then when I brew big I lower my efficiency a few % more just cause.

I know its not my crush. I know I do not have dough balls. I have been able to hit my numbers with a higher efficiency % before I started using the FB. My boil off rate is dialed in. I do not have a problem hitting my volume numbers going into the kettle and post boil.

So Im confused. when you create a recipe and account for the tun deadspace volume, does the recipe not calculate the expected OG taking this into consideration? what am I missing?

 

[Gixxer]

forgot to add I do an iodine test at the end of the mash so I'm confident I get complete conversion more or less

 

[Biscuits]

Is BS adjusting your grain bill weights to make up for the added volume left behind in your mashtun? I am wondering if this is just a simple matter of adding more water to make up for lost volume is also diluting your sugar yield and therefore lowering your efficiency?

 

[thekraken]

Did you add your measurement for space under the false bottom to "Mash Tun Addtion" or "Lauter Tun Losses"

I'd think it should be in addition. I imagine you have it set as losses so BS is adding extra water to compensate but 'thinks' it's not recoverable, but since it's just a false bottom it isn't 'deadspace' as the wort is still recoverable underneath the false bottom. Are you getting more preboil volume than what BS says you should get?

 

[Gixxer]

Truthfully I don't remember which one. I need to do some poking to see. I added the volume under the equipment profile on the right side of the popup that comes up when you edit an equipment profile.

 

[Gixxer]

I also probably should build a test recipe and see if the grain bill amount changes when I select the equipment profile. It does make sense that possibly the volumes are correct for water, but the grain bill is not adjusting.

 

[Oginme]

BeerSmith will not adjust your grain bill unless you do a "scale recipe". What it will do is respond to the brew house efficiency you put into the equipment profile (by changing the output numbers) and changes in water volumes (by increasing the mash efficiency to maintain the same brew house efficiency).

 

[Gixxer]

Gotcha. So then what is the point of putting a value in the tun dead space section in an equipment profile if it doesn't scale the grain bill? Just curious. But I do have a way ahead I believe

 

[thekraken]

BS needs to know the volume of the "dead space" in order to accurately calculate the required strike, sparge, preboil, batch volumes. Notice that when you change the those volumes in the equipment profile that the predicted gravities for a given recipe will change.

 

[doug293cz]

What is your lauter/sparge process? If you are not recirculating during the mash, the volume under the FB isn't really participating in the mash, and will contain wort that is more dilute than the bulk mash. Stirring really doesn't help, as you don't really get mixing with the wort under the FB. In this case you need to vorlauf enough so that the vorlaufed volume is more than the volume under the FB, in order to get the low SG wort back up into the mash. If you don't vorlauf enough, the first part of your first runnings will be lower SG, and the wort held at the end of run-off due to grain absorption will be higher SG, thus lowering your lauter efficiency significantly.


Brew on

 

[Gixxer]

I vorlauf anywhere from a gallon to a gallon and a half till the pour is clear before lautering. Drain the tun, sprage water goes in, stir, then vorlauf the same amount before draining.

 

[doug293cz]

I vorlauf anywhere from a gallon to a gallon and a half till the pour is clear before lautering. Drain the tun, sprage water goes in, stir, then vorlauf the same amount before draining.

So, what's the volume under your FB?

Brew on

 

[Gixxer]

4 quarts

 

[kevin58]

I know Brad has tutorials on the website but I found this guys equipment and mash profile setup explanation to be pretty straight forward.

Equipment set up:
https://youtu.be/QmW7pwQP5mQ

He also has a batch sparge mash setup and a BIAB mash setup.

 

[Gixxer]

I feel like 4 quarts is a lot of deadspace in a 10gl cooler. The FB does not quite rest on the bottom the way it should. The diameter of the FB is not quite small enough to get all the way down to rest on the legs. Need to grind down the diameter of the FB so I can lose some of that deadspace. For now I can lower my efficiency to compensate.

 

[thekraken]

You have a dip tube to the bottom of the cooler, correct?

 

[Gixxer]

Yes. After I drain the tun and remove the grains, there is only residual liquid in the bottom.

 

[doug293cz]

With a one gallon "deadspace" under the FB, I'd recommend vorlaufing two - three gallons to make sure you empty the low SG wort out of the deadspace prior to run-off. You should also be stirring well prior to vorlauf to make sure you don't have higher SG wort adsorbed/absorbed by the grits. If you are batch sparging you should also stir well before the vorlauf, and vorlauf the same as for the initial run-off.

Brew on

 

[Dcpcooks]

I never considered the volume under the FB to be dead space without a recirculation. That's a really smart observation.

As you say:
brew on