Head space in 5 gal carboy

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Someone posted a special plastic bag tapered at the top inserted into carboy then filled with water until the wine level reaches the top of the neck of the carboy. The bag keeps the water separated from the wine and allows complete top up of the carboy. I tried my first one several weeks ago and it seems to work great. Anyone else try topping up this way?

The one I've seen was developed by a guy named Wensi Peng who lives in Canada. He posts all the time on the FB Home Winemaking site, I've never seen him post here. Video: In the comments someone says this has already been commercialized, so there are probably other types out there.
 
1 gallon carboys

I ordered 1-gallon carboys. - ref headspace thread. ?
Last summer I ordered several sizes of LDPE cubes (cubitainer) for variable gallons racking. Sales lit says they have some O2 penetration so they may perform like an oak barrel, TBD. - They gosh down so the head space is low (40 or 50ml) and a rubber cork will keep it at that level 5 months.
I like em in process as moving 5 gallons to a friends house, or as a filter receiver, or for back sweetening, , , final opinion is out as a fermentation carboy.
 
Last summer I ordered several sizes of LDPE cubes (cubitainer) for variable gallons racking. Sales lit says they have some O2 penetration so they may perform like an oak barrel, TBD. - They gosh down so the head space is low (40 or 50ml) and a rubber cork will keep it at that level 5 months.
I like em in process as moving 5 gallons to a friends house, or as a filter receiver, or for back sweetening, , , final opinion is out as a fermentation carboy.
How do they act like an oak barrel? Not sure I see that. Don't you put these into your carboy and then put a bung. When I think act like a barrel, I would think they would have to contact the air.
 
How do they act like an oak barrel? Not sure I see that. Don't you put these into your carboy and then put a bung. When I think act like a barrel, I would think they would have to contact the air.

Apparently the type of plastic used for some of these things, the cube container/flextank, is somehow o2 permeable to a degree. Not enough to cause evaporation, but allegedly enough to benefit the wine. *they say
 
Apparently the type of plastic used for some of these things, the cube container/flextank, is somehow o2 permeable to a degree. Not enough to cause evaporation, but allegedly enough to benefit the wine. *they say

Oh, I see, I was (yet again, mostly normal) confused. These are plastic containers / flextanks. I misunderstood and thought they were something to be added to a container. DOHHHHHH!!!!!!

I think what confused me is the LDPE. I'm not sure that is the correct designation for flextanks for wine, but who knows. My mistake. Let's blame it on the wine tasting this afternoon.
 
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I also thought the suction bulb was to rigid for long term aging . So I took the Head Space Eliminator one step further and replaced the suction bulb with a cheap vacuum gauge from ( amazon $ 8.70 ) and a silicon applicator adapter . Now I know how much vacuum is in my head space at all time . I made 2 so far , 1 has zero leakage in 3 weeks holding at 17 inches and the other one has a few inches a day leakage .
 
I also thought the suction bulb was to rigid for long term aging . So I took the Head Space Eliminator one step further and replaced the suction bulb with a cheap vacuum gauge from ( amazon $ 8.70 ) and a silicon applicator adapter . Now I know how much vacuum is in my head space at all time . I made 2 so far , 1 has zero leakage in 3 weeks holding at 17 inches and the other one has a few inches a day leakage .

Nice idea. I might steal it. Will help me figure out a little issue. I realized recently that demijohns with spigots can’t hold the vacuum as is.
I was using the standard HE setup with the bulb and it was losing the deflation within minutes. When pump was running I noticed the valve also had a suction. I made sure it was tightly closed and still the same.
The standard demijohn spigots are metal and good quality. I haven’t tried yet but thinking a little rubber cap is needed so the vacuum holds. I normally don’t use the bulb, so I realized this from dumb luck. Luckily I only use it for very short term use anyway.
 
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How do they act like an oak barrel? Not sure I see that. Don't you put these into your carboy and then put a bung. When I think act like a barrel, I would think they would have to contact the air.
There is some oxygen vapor transmission with this plastic. That noted the company I worked for used to use 20 mil LDPE plastic liners on 1000 lb totes of low /6% moisture ingredient and give it a year shelf life so I am not too concerned. Ask me again when this is a year old.
Photo 20 liter (2.5 gallon) Cubitainer
 
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I also thought the suction bulb was to rigid for long term aging . So I took the Head Space Eliminator one step further and replaced the suction bulb with a cheap vacuum gauge from ( amazon $ 8.70 ) and a silicon applicator adapter . Now I know how much vacuum is in my head space at all time . I made 2 so far , 1 has zero leakage in 3 weeks holding at 17 inches and the other one has a few inches a day leakage .

I did not have much luck to find vacuum gauges that would hold vacuum for even short term use. I initially started out using a vacuum gauge, Please keep me informed - good luck

I found that even the check valve will also leak over time - that is why I supply a cap to cause a air tight seal over the valve.
 
I also was wondering if I could use a softer stopper like a ( double drilled silicon stopper ) to get a better vacuum seal around the carboy neck and stopper . My feeling is that my weak point is around the stopper and carboy neck . Time will tell
 
I did not have much luck to find vacuum gauges that would hold vacuum for even short term use. I initially started out using a vacuum gauge, Please keep me informed - good luck

I found that even the check valve will also leak over time - that is why I supply a cap to cause a air tight seal over the valve.
Steve, the issue usually is the thread, , what I do with my Gage is silicone tubing. First a size that fits 1/8 pipe thread and then another matching ID (maybe .5 mm wall) over that to snug down the bottom layer. Sounds like I should test it long term on a flask.

I also found the check valve did not hold, eventually wanted to replace it with a plastic valve with barbs on both ends. Push fittings would probably also do the same with rigid tubing.
 
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I also was wondering if I could use a softer stopper like a ( double drilled silicon stopper ) to get a better vacuum seal around the carboy neck and stopper . My feeling is that my weak point is around the stopper and carboy neck . Time will tell
There is a neat product at Home Depot called (silicon) fusion tape. It will stretch to any shape (as a valve stem that drips) seals against itself and all surfaces I have tried. It will stop any leakage with a clean rubber stopper.
 
I also was wondering if I could use a softer stopper like a ( double drilled silicon stopper ) to get a better vacuum seal around the carboy neck and stopper . My feeling is that my weak point is around the stopper and carboy neck . Time will tell




I also found the check valve did not hold, eventually wanted to replace it with a plastic valve with barbs on both ends. Push fittings would probably also do the same with rigid tubing.[/QUOTE]

The kit comes with vinyl caps to cover the ends of the valves for any chance of leakage - I even throw in an extra one in each package. (because some of customers were putting them on too far and had issues removing them)

Did you have these on - when the check valve would not hold ?
 
I have the caps on both of mine . I only push the caps on until the first barb .
One gauge set-up has been holding for 3 weeks at 17 '' inches doesn't move at all , the other one
moves about 1 or 2 inches a day . I'll wait till it gets below 5 inches and then try to reseal it again .
 
In theory, you could connect them all together, attach to a single pump, add a switch which kicks on whenever the pressure rises to 0.5Atm and off at 0.2Atm, and just leave it on. :)
 
Really like the gauge idea. Curious if using a brass hose fitting connector with 1/4" NPT Female and hose barb would work instead of the RTV silicone applicator? Because there is no graduated decrease in diameter the question may be what size hose barb would fit the stopper hole (e.g. in Steve's HSE kit stoppers)? 1/4" Barb?
 
Please let me know if I should go back and possibly redesign the headspace eliminator ? I have tried alot of the things you all are talking about - Originally all Daisy chained together - vacuum gauge attached

I wanted to make something that would help the average winemaker - and be reasonable in price as well. I believe at a going rate of 12 dollars for all that is included is pretty fair( custom drilled 2 hole pure gum stopper - 1 way check valve - vinyl cap - bulb - literature and hose adapter).

I am up for all suggestions - Thanks in advance.
 
Please let me know if I should go back and possibly redesign the headspace eliminator ? I have tried alot of the things you all are talking about - Originally all Daisy chained together - vacuum gauge attached

I wanted to make something that would help the average winemaker - and be reasonable in price as well. I believe at a going rate of 12 dollars for all that is included is pretty fair( custom drilled 2 hole pure gum stopper - 1 way check valve - vinyl cap - bulb - literature and hose adapter).

I am up for all suggestions - Thanks in advance.

Ehhh. I wouldn’t change a thing. Home winemakers are all DIY’rs by nature. So convos to rig/tweak something up is gonna happen regardless. And some interesting ideas been said.
I think they are great as is. I don’t use em for long term tho. Just few days-week tops. Headspace eliminators are a great tool if needed. But don’t want it to be a crutch and be ok with headspace.
 
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