Bayou classic dead space

I just recently put together a Kal clone HERMS system and have been pretty happy with it. I have done 2 batches but my concern is I used the Bayou classic MLT kit which uses a false bottom that sits at the 3 gallon mark. I know that is a lot of dead space but I have beersmith compensating that into my recipes. I am wondering though, my last IPA had an OG of 1.080 and I ended up in the 1.066 to 1.064 range doing 5 gallon batches ( I'm trying to get used to using the system before I make a 10 gallon commitment). I has about 32 qts of water for my dough in. Do you think this efficiency issue could be because of the deadspace? I am pretty sure my temperatures are ok because I double checked with a thermometer and I am happy with my crush using a roller mill. Has anyone else used these Bayou kettles and experienced the same problem? I don't want to resort to using just the bazooka screen if I don't have to because I don't know how it will hold up to a 10 gallon batch grain bill.

Also I have been having a problem with my grain bed floating during the sparge, I am wondering if that much dead space doesn't allow the grain bed to suck down properly at such a low flow like fly sparging?

Since you are recirculating, my guess is the dead space under the FB shouldn't really have an impact. Higher gravities will be less efficient FWIW. I would not fear the braid and large grain bills, jmo.

Try a batch sparge?

I asked this exact question a few days ago but didnt get a response (also upgraded my MT the a stainless 16g bayou setup... Like Wilserbrewer I assume because we recirculate during the whole mash the huge amount of dead space wont matter.(Except possibly when making English style beers that traditionally are made with a thicker mash)..I haven't actually used my setup yet since I have been rearranging my brew room and adding new hardware (GF bought me a stout 12.5g conical for Christmas whoo hoo!)
I have read though of people complaining that the bayou false bottom and bazooka tube lets too much grain through. Also that the bayou bazooka tube is not stainless and will rust if left wet or submerged FYI. They have recently redesigned the false bottom to be stronger though.
I myself bought the false bottom and bazooka tube separately (I use a bazooka tube from bargainfittings.com and its great for the $10 or whatever it costs)
I also use a 12" section of stainless braided plumbing supply line insulation inside my bazooka tube to filter it further since I use small 24v dc pumps which can bind up easily if grain were to get wedged inside.
I used this method for about 8 months with my cooler mt and it worked great.

It sounds like while you're compensating for the water under the false bottom that you aren't correspondingly compensating the grain bill. If that's the case, then that could cause you're worts to be lower gravity than you plan for.

Also regarding the belt and suspenders approach to the use of a false bottom and a bazooka screen, I created a gasket of sorts out of silicon tubing. Cut it to fit, fill it with water, and add a connector. It keeps the grain from seeping in around the edges.

stlbeer said:

It sounds like while you're compensating for the water under the false bottom that you aren't correspondingly compensating the grain bill. If that's the case, then that could cause you're worts to be lower gravity than you plan for.

Also regarding the belt and suspenders approach to the use of a false bottom and a bazooka screen, I created a gasket of sorts out of silicon tubing. Cut it to fit, fill it with water, and add a connector. It keeps the grain from seeping in around the edges.

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From what I understand beersmith compensates for this when you enter in the proper dead space volume under "My equipment" setup?.... thats what I read (and did). If thats not the case I would like to know more?....Please..

I think Beersmith should take your volume above the false bottom and use that for the mash thickness calculation. It will then add the dead space to the strike water volume, and subtract it from the sparge water volume, so that you get the right volume in the kettle. Obviously, this will reduce the amount of sparge water used (if you sparge), which could impact efficiency.

If I had a dip tube going to the center of the pot instead of the bazooka screen do you think that might prevent channeling and boost my efficiency?

hoss1550 said:

If I had a dip tube going to the center of the pot instead of the bazooka screen do you think that might prevent channeling and boost my efficiency?

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I honestly dont see how it would help myself.... The false bottom above should be enough to prevent channeling.

stlbeer said:

Also regarding the belt and suspenders approach to the use of a false bottom and a bazooka screen, I created a gasket of sorts out of silicon tubing. Cut it to fit, fill it with water, and add a connector. It keeps the grain from seeping in around the edges.

Click to expand...

I recall someone trying to use both the B/C false bottom and bazooka screen resulting in stuck sparges. I think it best to pick one or the other, the bazooka doesnt filter well with only the flour that passes the FB.

wilserbrewer said:

I recall someone trying to use both the B/C false bottom and bazooka screen resulting in stuck sparges. I think it best to pick one or the other, the bazooka doesnt filter well with only the flour that passes the FB.

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I read that thread too... Guess I need to find out myself since im using a different bazooka tube and bayou changed thier false bottom recently... plus Im having a hard time seeing additional filtration causing the issue perhaps he was pumping too fast?
I plan on brewing later today, I will post my results.

augiedoggy said:

I read that thread too... Guess I need to find out myself since im using a different bazooka tube and bayou changed thier false bottom recently... plus Im having a hard time seeing additional filtration causing the issue perhaps he was pumping too fast?
I plan on brewing later today, I will post my results.

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Yes I agree, too many variables b/w everyone's different methods. I see the braid potentially sticking because it is trying to lauter only what passes the F/B, or flour only??? Maybe w/ slower flow or coarser crush (less flour) it doesn't happen...

Yoop solved her issues by using a bag and FB in the MT, fwiw. This is one of the many reasons I don't recirc., too
I find simple

cheers!
wilser

wilserbrewer said:

Yes I agree, too many variables b/w everyone's different methods. I see the braid potentially sticking because it is trying to lauter only what passes the F/B, or flour only??? Maybe w/ slower flow or coarser crush (less flour) it doesn't happen...

Yoop solved her issues by using a bag and FB in the MT, fwiw. This is one of the many reasons I don't recirc., too
I find simple

cheers!
wilser

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See I have never had a stuck or slow mash/sparge while recirculating...30+ brews now recirculating but I use 12v/24v pumps so only 1 1/2- 2 gallons per minute after restrictions.

augiedoggy said:

See I have never had a stuck or slow mash/sparge while recirculating...30+ brews now recirculating but I use 12v/24v pumps so only 1 1/2- 2 gallons per minute after restrictions.

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Yea, I agree w/ your low flow. I think some mistakenly think they need to recirc 5-10 gpm or more and stick it good, or better yet collapse a FB.

Well I'm glad I tried this... brewed a milk stout last night and everything went perfect on my new setup... the bazooka tube with the braided stainless sleeve inside it and the BC false bottom worked perfect without even a hint of slowing up... I was able to start my 3.2.GPM pump very slowly with my pwm controller and slowly ramped it up to 100% over the course of a few minutes... my new rims heater with the 25" 1,000w cartridge heater element had no issues maintaining a perfect 152 degrees while using less than 50% duty cycle on the element...
Beersmith had me mash in with 26.75qts because of the dead space and in the end I had the beer finish at 1.063 even though at 75% efficiency it should have been 1.058. I had no issues with fly sparging either.
I'm a very happy brewer right now... I was worried that my uninsulated bayou classic MT would not be able to maintain even temps even with the rims. Even though my brew room was cold due to and open window and exhaust fans Both the rims pt100 temp probe and the dial thermometer at the base of my my exit were actually in synce within one degree! I did calibrate the both during setup of the system. I thought I would have more thermal loss.

Few comments: Space under a false bottom is not called dead space. There's no traditional definition for that but I call it slack space. It's area where liquid mash resides but thick mash doesn't. Dead space (which beersmith compensates for) is liquid that cannot drain out of the tun when you do a full drain. IMHO, any vessel should have a siphon/dip tube of some kind to reduce dead space even if it's just an elbow threaded into the bulkhead.

Thanks Bobby, I will try adding one for my next batch

Bobby_M said:

Few comments: Space under a false bottom is not called dead space. There's no traditional definition for that but I call it slack space. It's area where liquid mash resides but thick mash doesn't. Dead space (which beersmith compensates for) is liquid that cannot drain out of the tun when you do a full drain. IMHO, any vessel should have a siphon/dip tube of some kind to reduce dead space even if it's just an elbow threaded into the bulkhead.

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Good to know...I wish I could find a definition from beersmith because there is a lot of misinformation on this here. I did a search on this a week ago and here are two other threads here as well as one on the electric brewery forum in which the "dead space" in beersmith was discussed and it was explained there that it was in fact the volume under the false bottom as well as recirculating wort path (hoses to and including rims,herms and back through sparge arm). since the space under the false bottom and in these hoses is liquid without grain this would also explain why when you increase this setting it increases you mash water volume...

Bobby_M said:

Few comments: Space under a false bottom is not called dead space. There's no traditional definition for that but I call it slack space. It's area where liquid mash resides but thick mash doesn't. Dead space (which beersmith compensates for) is liquid that cannot drain out of the tun when you do a full drain. IMHO, any vessel should have a siphon/dip tube of some kind to reduce dead space even if it's just an elbow threaded into the bulkhead.

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I think it's called foundation water. There's some information here, http://en.wikibooks.org/wiki/Brewing/Lautering, but not a ton.

I found similar information in a morebeer article, again referencing lautering separate from mashing.

http://morebeer.com/articles/lautering_for_highest_efficiency

"If you use a mash tun separate from the lauter tun, the first step in lautering is the physical transfer of the mash. When using a separate lauter tun, it is important to cover the false bottom with preheated water. This water is called foundation water and provides a kind of support that prevents the initial force of mash transfer from clogging the false bottom. The foundation water also helps to preheat the lauter tun, which aids in maintaining the final mash temperature."

As definitive as I can get it, dead space is the amount of wort that cannot be recovered out of the mash in a batch sparge. In a fly sparging rig, there's still the concept of dead space, but it's more of an effect on lauter efficiency because that zone can hold on to the first wort as your lauter/sparge runs out above it.
In the case of a large area under a false bottom, it may include some dead space, but maybe not. Let's say your false bottom is 6" above the bottom but you have a diptube so all the liquid that is ever in the tun will drain out fully. That's a lot of "slack space?" but zero dead space. See, when you click "adjust mash volume for deadspace" in BS, it has you add that extra liquid so that you're able to drain out as much wort as you need for the preboil volume.

Liquid that is in slack space will still drain out and is functionally still part of your mash. Where it plays tricks on you is in making the mash above the false bottom FEEL like a thicker mash when stirring. In a recirculating mash, it's only problematic when you're already starting with a relatively thick mash like 1 quart per pound. A simple rule of thumb is to figure out how much strike volume is required for 1.25 qts/lb, then just add more strike water equal to your tun's slack space. That makes the mash feel like 1.25qts/lb when stirring but for the rest of the calculations (such as required sparge volume), you'd use the ACTUAL number.

So, in a simple mash tun where you'd just going to gravity drain into a collection bucket or kettle, the dead space is just the wort that won't drain out (a simple water only test would get you this figure). In a more complex system with pumps and several feet of tubing, the dead space would be liquid that won't drain out of the tun AND anything that is still trapped in the plumbing when your pump loses prime. In both of these cases, you'd tell beersmith that this is dead space and you will compensate for it with more strike water. This is still a different adjustment than space under a false bottom and beersmith doesn't address the latter at all. It's a manual decision and it can easily be made just by mashing thinner across every batch (such as 1.7 qts/lb) and you'll do better in a recirculating system thinner anyway.

stlbeer said:

I think it's called foundation water. There's some information here, http://en.wikibooks.org/wiki/Brewing/Lautering, but not a ton.

I found similar information in a morebeer article, again referencing lautering separate from mashing.

http://morebeer.com/articles/lautering_for_highest_efficiency

"If you use a mash tun separate from the lauter tun, the first step in lautering is the physical transfer of the mash. When using a separate lauter tun, it is important to cover the false bottom with preheated water. This water is called foundation water and provides a kind of support that prevents the initial force of mash transfer from clogging the false bottom. The foundation water also helps to preheat the lauter tun, which aids in maintaining the final mash temperature."

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I'll sort of agree. Foundation water in both articles are specifically related to dedicated lauter tuns and I don't know a single homebrewer that does that. I guess we can call liquid under a false bottom "foundation space" but it would only be "foundation water" when we first add the strike water. Once you dough in it would be "foundation wort". :rockin:

I still like "slack space" and I'll stick with that. If I put it in enough Wiki's across the internet, it will be true