small batches and conical fermenters. worth it or just excessive?

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SanPancho

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that's my question. wife is now a wine drinker for the most part so 5gallon batches are a bit much. usually try to always have two beers on tap, so half batches makes most sense. have dealt with carboys, fermenting in kegs, plastic conicals, etc. the plastic conicals were mostly good, but still had no "safe" way to do dry hopping. id have zero reservations about just buying a little unitank conical if it wasnt for the damn half batch issue.

so- if anybody out there is doing half batches in a unitank conical- is it a total pain? a bit excessive?

i mean your typical keg is gonna be 2.5 or 3 gals, but that's what you need to be left with after your losses-- yeast dump, hops crashed, etc. so how much do you need to put into the conical to be able to get 2.5 or 3 gals of clean beer at the end? we're talking IPA levels of hopping typically. so decent amount of loss there. are we talking about starting with like 5 gallons to finish with 2.5 or3? less?

and secondly- im assuming theres going to be a problem with the typical cooling coil type setup. id wager very little to barely any of the coils will be submerged as that small volume. are you basically stuck going with the ferm chamber in that scenario?

would love to hear from some folks who've tried half/small batches in the conicals!
 
Doing my first small batch in a Flex+. Losses are proportionately higher because of fixed amounts in tubing, and in the bottom of the kettle and fermenter. I have no math for you, though. If you lose a gallon in a five gallon batch, you'll also lose about a gallon in a smaller batch. Cheers!
 
Yes of course, the equipment losses are static, so whatever you’re losing under the racking arm is the same. But on our tanks I always dump yeast before dry hop, so that’s in addition to the static losses. I guess there isn’t a way to calc that figure other than just make an assumption- if you start with 6g and dump a quart, I’ll assume 3g will dump a pint.

20/20 says that should have been the focus of my question- typical loss figures that folks see.
 
It seems reasonable to assume that yeast / trub dump size will be proportional to original volume in the fermenter. Maybe an experienced conical brewer will chime in.
 
actually, i was just able to find some info that sort of answers few of my questions. the brewbuilt/morebeer folks actually give you some specs on volumes. so it looks like i should be able to use thermowell and sample/racking valve looks like it will always be submerged.

and from what i can see they ditch the 90 elbow at bottom that everyone else uses which will also lessen the losses a bit. with a floating dip tube instead of racking arm i think that solves most of my concerns.

i've decided to use a side by side fridge as the ferm chamber, giving me the freezer side to store hops, yeast bank, starter wort, etc so no longer care about cooling coils. and this one is an inch narrower vs the cf5 so that might help finding a cheap craigslist used fridge.

unfortunately they're out of stock.......
Screenshot 2022-03-10 085311.jpg
 
The CF5 is built for half batches. The cooling coil, thermowell, sampling valve, etc etc are all low enough to work. So far I've done 3 or 4 gallon batches that have worked great. I haven't fully characterized my losses yet, so I can't tell you how much extra you'll have to make. But the ability to do half batches was what pushed me to the CF5.
 
The CF5 is built for half batches. The cooling coil, thermowell, sampling valve, etc etc are all low enough to work. So far I've done 3 or 4 gallon batches that have worked great. I haven't fully characterized my losses yet, so I can't tell you how much extra you'll have to make. But the ability to do half batches was what pushed me to the CF5.
thanks. good to know. all the manufacturers claim you can do half batches, but always a question whether thats for real or just a technicality they proffer for marketing purposes. my goal would be to finish with about 3, and rack a nice clean 2.5 into serving keg.

i had been focusing on the CF5, but as i noted above the brewbuilt one is a bit narrower, and has 4 legs. so i think i'll just wait for that one. morebeer is actually my (our?) LHBS so makes it easy getting any other parts/pieces on gear. and if for some reason it just doenst work for me i can easily drop it back off and say thanks anyways. easiest return ever.
 
no. havent even been here a year and been slammed with work the whole time, getting house fixed up, etc. etc. barely had time to brew anything.

i'll shoot you a pm. got some stuff you may be interested in.
 
The CF5 is built for half batches. The cooling coil, thermowell, sampling valve, etc etc are all low enough to work. So far I've done 3 or 4 gallon batches that have worked great. I haven't fully characterized my losses yet, so I can't tell you how much extra you'll have to make. But the ability to do half batches was what pushed me to the CF5.
I have a CF-5... haven't done a small batch yet so I've not experimented with volume levels. What volume of wort is needed to completely cover the uppermost side port? I realize Spike uses that port for the thermowell but I have swapped positions and now use the sample valve in the top port. Thanks!
 
With 2.5 gallons, I had to tip my Flex+ to get a sample from its upper port, fwiw. CF5 highest port seems to be 2.7gal. per their drawing:

https://f.hubspotusercontent20.net/hubfs/7288227/Conical Cutaway Drawings.pdf

awesome. nice find.

im a little skeptical of their figures as i'm thinking they're not including the loss in the elbow below the cone. could be wrong, but thats what it seems like to me.
thermowell is at 2.7gal mark, so you really cant go below about 3 to get decent reading from what it looks like in drawing. but it does look like their cooling coil wont be an issue for a small batch. and racking arm pretty much empties everything out.

yeah, does in fact seem like these guys actually do have a tank that will work pretty well for half batches.
 
Yup. And you can move the thermowell to the lower port, and just sacrifice samples for very small batches. (Some people prefer this anyway so that the sample port doesn't gather as much crud)
 
awesome. nice find.

im a little skeptical of their figures as i'm thinking they're not including the loss in the elbow below the cone. could be wrong, but thats what it seems like to me.
thermowell is at 2.7gal mark, so you really cant go below about 3 to get decent reading from what it looks like in drawing. but it does look like their cooling coil wont be an issue for a small batch. and racking arm pretty much empties everything out.

yeah, does in fact seem like these guys actually do have a tank that will work pretty well for half batches.
I agree with your skepticism. Volume markings are often not exactly as stated, especially when you have the option of different equipment configurations at the dump port. I always use the top port for sampling... less apt to capture solids. As a work around, I could connect the sample valve to the racking port butterfly valve if need be.
 
Cmon. Somebody must be doing small batches..
I've done a small batch in my conical but it was a pain for all the reasons you mentioned. Plus the Trum never completely settle to the conical bottom. It stayed on the angled cone. Totall pain. I only bottle or keg from conical. Sort of overkill but yeah well. Good luck.
 
i've decided to use a side by side fridge as the ferm chamber, giving me the freezer side to store hops, yeast bank, starter wort, etc so no longer care about cooling coils. and this one is an inch narrower vs the cf5 so that might help finding a cheap craigslist used fridge.

How are you going to control temperatures in the fridge section without cycling the freezer section on and off? I didn't think that was possible.
 
With smaller batches it's usually easy (and more beneficial) to minimize or even recover leftovers.
For example, leftover wort in the kettle than be strained from the trub, re-pasteurized then added to the fermenter.

Recovering beer is more difficult as oxidation plays a big role, but you can usually reduce and minimize losses with a few keener, more diligent approaches.
 
How are you going to control temperatures in the fridge section without cycling the freezer section on and off? I didn't think that was possible.
in one scenario, ill go with a "standard" setup of having the temp controller turn the whole fridge/freezer off and on. i dont really care if the hops and starter wort packs cycle from frozen to really cold. the hops will still be cold. the starter will still get boiled. and the yeast bank gets put into a small foam ice chest with cryo pak so it shouldnt cycle anywhere near what the freezer compartment would do. i have a little temp logger i plan to set up for the first ferment and see what the effects are on the yeast bank box. if it gets too warm i'll just keep those in the freezer in the kitchen. its only about 5 or 10 small pouches of yeast. not a big deal if it doesnt work out and i leave them upstairs.

as for the other scenario- its fairly common to have units with separate temp controls for freezer and fridge, even older units i'm likely to find off craigslist. i'll have the fridge on one of the warmest settings, but keep the freezer nice and cold. instead of just relying the fridge's internals to move the cold air i will cut a hole in the wall that divides the chambers, and use an inline fan run off a temp relay to push colder air into the fridge chamber as needed. got the idea from an ac guy when i was asking him about residential fridges and the way the work, how the cold flow is established, how to get to crash temps in a fridge section, etc. its been so long i cant remember if he said to do that all the time, or just when it was time to cold crash. maybe it doesnt matter.

so as long as i can find a unit with separate temp controls i'll go with the second scenario. if i cant find one, i'll do the first.

With smaller batches it's usually easy (and more beneficial) to minimize or even recover leftovers.
For example, leftover wort in the kettle than be strained from the trub, re-pasteurized then added to the fermenter.

Recovering beer is more difficult as oxidation plays a big role, but you can usually reduce and minimize losses with a few keener, more diligent approaches.
i'm not gonna go nuts trying to recapture every ounce, i just was hoping to get some general ideas from folks what sort of losses we're talking about here. i dont have a problem with needing 3.5-4gals in kettle to wind up with 2.5 in the keg. just wanted to make sure it wasnt like 4-5gals to start and only wind up with 2.5. that seems excessive. but given the design of the morebeer/brewbuilt unit it seems like its set up in a way that really minimizes those static losses. and all other things equal a narrower vessel is easier to drain completely than a wider one. not sure that 1" makes a huge difference vs the cf5 but it might help me find a fridge that works more quickly/cheaply.
 
in one scenario, ill go with a "standard" setup of having the temp controller turn the whole fridge/freezer off and on. i dont really care if the hops and starter wort packs cycle from frozen to really cold. the hops will still be cold. the starter will still get boiled. and the yeast bank gets put into a small foam ice chest with cryo pak so it shouldnt cycle anywhere near what the freezer compartment would do. i have a little temp logger i plan to set up for the first ferment and see what the effects are on the yeast bank box. if it gets too warm i'll just keep those in the freezer in the kitchen. its only about 5 or 10 small pouches of yeast. not a big deal if it doesnt work out and i leave them upstairs.

as for the other scenario- its fairly common to have units with separate temp controls for freezer and fridge, even older units i'm likely to find off craigslist. i'll have the fridge on one of the warmest settings, but keep the freezer nice and cold. instead of just relying the fridge's internals to move the cold air i will cut a hole in the wall that divides the chambers, and use an inline fan run off a temp relay to push colder air into the fridge chamber as needed. got the idea from an ac guy when i was asking him about residential fridges and the way the work, how the cold flow is established, how to get to crash temps in a fridge section, etc. its been so long i cant remember if he said to do that all the time, or just when it was time to cold crash. maybe it doesnt matter.

so as long as i can find a unit with separate temp controls i'll go with the second scenario. if i cant find one, i'll do the first.

Very interesting!

When you get the fridge, please start a thread showing your build, how you did it, and how it works!
 
I'm a big fan of the 3 gallon fermonster with a ball lock enabled lid and a floating diptube. Granted I mostly brew 5.5 gallons and split it between two 3G fermonsters for yeast experimentation but I do get a full 2.5 ball lock corny out of each one. The CF5 can handle it but if you want cold crashing, you need to put it in a refrigerator as the coil is useless at 2.5 gallons.
 
so this is how i ended up rigging the fridge. essentially the top corner right above the freezer section has a port that blows cold air into the fridge. essentially you just pull all of that stuff out of there (removed the icemaker in the freezer too) and you have a small rectangular hole between the chambers.
IMG_8244.jpg

here's closeup of the port between freezer and fridge
IMG_8245.jpg

that rectangular area is almost a perfect match for a 4" fan i had from old freezer unit, it has a side output design that pulls air from the flat side of the unit and but spits it out perpendicular to the axis of the fan, blowing the air out the side. and wouldnt ya know it the fans outlet port is almost exactly the same size as the rectangular hole in the fridge wall. so other than using some foam as shim to get the vertical placement to line up, it was super easy.
IMG_8246.jpg

and luckily for me i was now able to keep all the baskets and shelves in the freezer for hops, yeast bank, etc. as for the ferment chamber, i also have space to keep two shelves in the door, as well as a shelf and drawer up at the top with a good amount of room above the conical. i'll have to check if there's enough room when i put a dry hop rig on it but for now i think i've got plenty of storage.
IMG_8247.jpg

going to connect the fan to an inkbird for cooling, but for now i'm just letting it run with no air movement between the two chambers. want to see what sort of temp i get when there isnt any air movement, hopefully something relatively close to ambient so i dont have to go with heat wraps and whatnot. but worst case if its too cold in the fridge, id just leave it outside with a heat wrap as bsmt doesnt really get warmer than mid 60s maybe.
 
My two cents: Conicals are almost always excessive on a 5 gallon (or smaller) homebrew scale. BUT the added convenience and function offered in a good conical are definitely great if you can swing the cost.

I do 5 gal batches and upgraded this year to spike cf5 fermenters... they are crazy easy to clean, have tons of utility in the function of the dump and TC ports, and they look great. DO I need them to make good 5 gal batches of beer, of course not, but I sure am happy I made the upgrade.
 
My two cents: Conicals are almost always excessive on a 5 gallon (or smaller) homebrew scale. BUT the added convenience and function offered in a good conical are definitely great if you can swing the cost.

I do 5 gal batches and upgraded this year to spike cf5 fermenters... they are crazy easy to clean, have tons of utility in the function of the dump and TC ports, and they look great. DO I need them to make good 5 gal batches of beer, of course not, but I sure am happy I made the upgrade.

That was one of the motivators for me getting the CF10 and being able to ferment a double batch in a single vessel. Had I bought my Fermzilla rounder before my Spike Flex+, I'd probably would have gotten another Fermzilla (or 3) instead and not even thought about the Flex+. They're pretty expensive now!
 
SanPancho that's an interesting way to approach that issue. I also ferment, cold crash and lager in a side by side. They utilize a thematically controlled diffuser to move cold air from the freezer compartment into the refrigerator. I want to figure out how to rewire the diffuser to operate by the use of an inkbird instead of the manufacturers controller. It can't be very difficult. It's a simple little fan that turns on and off by an internal controller.

If anyone reading this thread has knowledge on how to wire the diffuser to operate with an external controller, please chime in.
 
@SanPancho what are your thoughts with the small batches in the conical so far? Have you put a batch through it yet?
not yet, unfortunately im back at work and have just been totally swamped for the past few weeks now that the spring buying season is in full swing. then there was easter vacation, kid started soccer on sundays, etc. etc. need to grow up a new pitch of my favorite brett i just got in the mail. i'm going to do a full batch as soon as i can of a farmhouse brett with some red wine. so no report yet on the half batches in the x1. but looking forward to getting one in there as soon as brett finishes primary.
SanPancho that's an interesting way to approach that issue. I also ferment, cold crash and lager in a side by side. They utilize a thematically controlled diffuser to move cold air from the freezer compartment into the refrigerator. I want to figure out how to rewire the diffuser to operate by the use of an inkbird instead of the manufacturers controller. It can't be very difficult. It's a simple little fan that turns on and off by an internal controller.

If anyone reading this thread has knowledge on how to wire the diffuser to operate with an external controller, please chime in.

i put up a different post with an initial "success" report about a week ago. long story short, you need to seal the hell out of the compartments, make sure there is ZERO air getting through, or you're gonna get anywhere from like low 30s (when i started) to maybe 39/40F, before i found the last "leak". took me a few tries, but now i've finally got it sealed up. now the freezer stays frozen, and the ferm side stays right at 49-50F. only get cold air when the controller calls for it. for lagers its almost perfect. for ales i'll need heat wrap.

i threw my diffuser away like a dummy, but im not sure that would have been so easy. first off, my diffuser wasnt a fan. it was essentially a fixed louver plate, and then another louver plate on top of the fixed one, that slid back and forth to open/close the louver vents and allow cold air to come through.
basically, the inkbird is an on/off switch. but i got the impression the diffuser motor wasnt just on/off, but that it got a modulated signal to open a little, a bit more, alot, or all the way., or close itself. it comes from the controller board of the fridge so i assume it had some sort of logic behind its signalling. something like low, medium, high, etc. doenst seem compatible with inkbird type controllers.


i did have an idea - you could yank the diffuser motor out and swap it for a solenoid. you'd match the throw length of the solenoid to the travel distance of the diffuser cover plate. it'd be normally closed via the solenoid spring, then opens for cooling. but i realized it'd be like $20 for the solenoid, $6-7-8 for the 12/24v power adapter, and then having to figure out how to make the connections, get it secured, test it, etc. i had the fan already, spent $7 at home depot for the louvered plate, figured that was good enough since i'm right where i wanna be with an ambient temp of like 50F.
 
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