Pressure Transfer with SS Brew Bucket

SS Brewtech makes an excellent entry level stainless steel fermenter called the Brew Bucket. At an affordable price, the Brew Bucket is a worthwhile upgrade for anyone looking to move away from glass. With an entry level product, you can not expect all the bells and whistles. One missing feature from the Brew Bucket is the ability to pressure transfer your beer between the Brew Bucket and a keg. Luckily, a simple modification gives you this ability with a few added bonus features.

What’s the point?

First off, lets take a look at why we would want such a modification. Oxygen in beer plays an interesting roll. In fermentation, you want oxygen in solution to provide a healthy environment in which the yeast can grow. After fermentation has completed and the yeast have displaced most oxygen with CO2, oxygen is enemy number one. Any additional oxygen that comes in contact with your beer helps drive oxidation which affects taste and shelf life. This is especially important in lighter hop forward beers whose volatile hop components will be the first to be destroyed by excess oxygen. Using CO2 to push the beer from your Brew Bucket into a keg is one important way to avoid this contamination.
Another positive for this process is the ability to transfer your beer without need of a gravity assist. Even though the Brew Bucket is 10000% easier to move around than a glass carboy (it has handles!), not having to lift 45 lbs of beer to an elevated position is a bonus.

Parts

We need a way to easily pressurize the fermenter. The following parts list will allow you to build a setup that will sit on top of the fermenter and act as a blow off during fermentation as well as a way to pressurize the tank through a ball lock gas post. A few of these are easiest obtained through SS Brewtech and have been noted as such. The rest of the list can be purchased through local home brew stores, or if you must, Amazon.

• TC Clamp 1.5" [SS Brewtech link]
• TC Gasket 1.5" [SS Brewtech link]
• TC Bulkhead 1.5” [SS Brewtech link]
• Drill Bit 42mm Hole Saw [SS Brewtech link]
• Hose Barb and Pressurized Transfer Fitting [SS Brewtech link]
• Stainless Steel Tee NPT Female, 1/2"
• Stainless Steel Ball Lock Gas NPT Male, 1/2"
• Stainless Steel Mini Ball Valve NTP Female X Male, 1/2"
• 2 x Stainless Steel 3/8" Hose Barb x 1/2" NPT Male
• 4 foot section of 3/8" ID vinyl tube
• 3 x hose clamps 3/8"

Setup

Once you have all parts necessary, they will need to be assembled to resemble the following picture.

The last step is probably the hardest. You will need to drill a 42mm hole in the Brew Bucket lid to accept the TC bulkhead. In the parts list is a carbide drill / hole saw by SS Brewtech. This is what I used and it worked well. When drilling stainless, it is important to use lubricant, and to keep the drill speed low, 200-300 RPM. It is best if you have a drill press although I am sure you could make it work with a hand-held and some patience. It is a good idea to use a file with a rounded face on the hole to deburr any sharp edges.

When you are ready to put together your fermenter on brew day, your assembly will include these new parts. During active fermentation, keep the ball valve open and put the hose end into a jar filled with sanitizer. This will act as your airlock / blow-off. When you are ready to transfer to a keg, close the ball valve to prevent CO2 from escaping when you pressurize.

Transfer Process

Keg Prep

None of this matters if your keg is not purged of all oxygen first. Fill your keg with water and then use your CO2 tank to push that water out. Congratulations, you now have a keg devoid of oxygen.

Steps

1. Close ball valve on blowoff tube at the top of the Brew Bucket
2. Connect Brew Bucket output to liquid post of keg
3. Open pressure relief on keg or attach a connector to the gas post to allow CO2 in keg a path out. Optionally you can run some tube from the gas post into a container of water to act like an airlock
4. On CO2 tank, turn down regulator to 0 PSI
5. Connect CO2 tank to gas ball lock post at the top of the Brew Bucket
6. Open the mini ball valve at the output of the Brew Bucket
7. Very slowly, turn up the pressure using the CO2 regulator until it reads 1 PSI.

The transfer setup will look like this

Example Images

Bonus Features

This pressure transfer modification has two other uses!

• With the ball valve open during fermentation, the setup acts as a blow-off.
• After fermentation, close the ball valve and cold crash without worrying about sucking blowoff liquid into the fermentor. You can also introduce some additional CO2 to the fermenters headspace using the gas post if worried about pressure differences during cold crash. Remember, 1 PSI only.