* first of all “static” degassing can be done with a five inch Hg vacuum, it will be time dependent which basically means if I pull 25 inches on a FULL glass carboy in the photo below the pump just hums waiting for turbulence to bring more gas out, ,,,, it really won’t degas faster than the safer five inch vacuum. Expect it to take about twelve hours to reach the low CO
2 equilibrium.
My feel is that you can’t do reliable vacuum without a vacuum gague and considering Home Depot will get one to their service desk for $12, ,,, it is cheaper than a busted carboy and the set up below has one for the pump and a two hole check valve & gauge setup on the carboy. This morning it is at about 5.8 inches Hg after being “stabilized” three weeks ago.
View attachment 72145
* degassing follows Henry’s law, that is the soluble gas is proportional to the partial pressure in the 125ml of head space. The functional definition of a
degassed wine is that it will maintain five inches Hg of vacuum for half an hour. ie it doesn’t matter if it is squeaky clean, what matters is if you vacuum cork or vacuum transfer you don’t create a foam that sucks into the pump. To control the vacuum I am collecting parts for an on off timer to cycle the pump rather than letting it humm, ,,, (got a spare octal socket handy/ I have the timer on the work bench)
* there are a variety of food grade containers on the market and if you look enough you will find several choices in the two gallon range. The glass on the left was sold as a “pickle jar” by Wallyworld, it holds two gallons. The cover on it is a 120mm food grade silicone “bowl cover”. The container on the right is my plastic vacuum chamber which consists of a flexible 1/4 inch plastic round with a neoprene round for a gasket and a brass 1/8 NPT fitting tapped through. When I build the next one it will have a food grade silicone “baking sheet” instead of neoprene. Yes it flexes inward, look for “Lexan “ which will flex.
If you want more details PM me.
AGAIN DO NOT OVERDO THE VACUUM WHEN DEGASSING! If you want to pull over ten inches pulse your AIO pump for one or two hours till the foaming stops, ,,,, and hope the container survives the vacuum load.