Cheap 5$ Blow-off Tube for a Better Bottle - Requires some advanced tools

You will need:
1 #10 Bung - this is your standard rubber bung that will fit a Better Bottle
1 3/4" ID - 1" OD Vynil tube cut to length - make sure your tube is 1" OD, as Home Depot has failed me in the past with OD measurements.

1 1" Spade Drill Bit, it looks like this
1 Impact Driver - make sure your spade bit is the correct fitting, usually 3/8"
1 Table Vise Clamp
1 Goggles
1 surgical mask
1 apron

This procedure should explain itself. You are using a wood spade to drill a hole 1" through your bung, which when drilled through will fit a 3/4" tube as a blowoff. It is absolutely necessary to use an impact driver as a conventional cordless drill will not facilitate enough torque to do the job.

Tighten the bung onto the vise, which will contort it's shape. Use your free hand to push the other sides to make the bung look more like how it would normally. Slowly impact drive through the bung; it will take 5-10 minutes.

This makes rubber ash fly everywhere - use protection and cover your mouth and wear an apron or slack clothes.

The hole made will not look pretty but it will be structurally sound and the tube will fit in with some effort.

This project will not save you any money over buying that whacky PVC blowoff kit seen online unless you already have these tools. And since you likely have the bung already, the 4' of tubing set me back just under 5$, just over 5$ if you want to start from a new bung (I used a predrilled bung just fine).

NOTE: I still would suggest an impact driver over a big plug-in drill or hammer drill as you need one free hand to hold the bung in shape, unless you want to use a large hand vise grip to hold it, but I think that would be putting down too much power... but it's worth a shot, I suppose.

Does anyone know if it's true that bungs drill easily if you freeze them with dry ice?

I made one the same way. If you're saying advanced tools are required, I'd recommend the use a drill press, which is how I did mine.

I just use a bung, the bottom part of a 3 part airlock and tubing. No drilling or mods needed

No pic.

I can post one if someone wants.

I recently picked up some tubing that fits OVER the pre-drilled hole in the BB bung (as opposed to in the hole, which restricts flow too much), and it works great. I want to say it's 3/4" ID.

Any particular reason you didn't just use a carboy cap for < $5 and call it a day?

nickmv said:

Any particular reason you didn't just use a carboy cap for < $5 and call it a day?

Click to expand...

I used a orange carboy cap and 1/2" tube last night on a brew...and today, there was a mess in my ferement chamber...guess i'm gonna need something better I went with this set up as alot of people said it works...but that 1/2" tubing got clogged for me.

It's funny you mention that. I actually am fermenting a DFH 90min IPA right now and the tube is getting a little clogged, as the bubbles come out in rapid succession all at once, then a long pause (presumably a buildup), and another release.

I've been brewing 3.5 yrs and have never had an issue though as far as it getting completely backed up. I'm debating washing this one out though.

I used a hole saw and a regular drill. I held the bung in my hand, and drilled through with the hole saw. Worked like a champ. Obviously you want to not be an idiot and saw into your hand, but as long as your not a monkey or didn't eat too many paint chips in grade school, I'm sure you can figure out how to do it. The hole saw spreads pressure over 360 degrees of contact so deformation didn't happen, and if you can open a jar of pickles you can hold it still.

So, cliffs notes:
Hole saw.
Drill.
Hold bung.
Cut.

People who should not try this:
Forrest Gump
Grandmas and/or Grandpas
Delicate kittens
Zombies w/o hands

nickmv said:

Any particular reason you didn't just use a carboy cap for < $5 and call it a day?

Click to expand...

Carboy caps fit better bottles?

adamc said:

I just use a bung, the bottom part of a 3 part airlock and tubing. No drilling or mods needed

No pic.

I can post one if someone wants.

Click to expand...

I've tried this method and had clogging issues, since you're dealing with such a tiny opening. I went with the method posted by the OP so I could go with 3/4" ID tube and not have to worry about it again.

Markd27 said:

Carboy caps fit better bottles?

Click to expand...

Absolutely, the orange ones do. They stretch a bit so try to keep the one you used assigned to a BB, as it'll probably not be quite airtight on a standard carboy after several uses.

Honestly, it'll probably lose its airtight ability 50% of the time on the BB (just due to the stretch), but it works just fine. Remember, it only needs to be so tight as to keep air out, and CO2 certainly isn't going to be letting air in. I've been using them for a while with no problems on my BB's.

Markd27 said:

I've tried this method and had clogging issues, since you're dealing with such a tiny opening. I went with the method posted by the OP so I could go with 3/4" ID tube and not have to worry about it again.

Click to expand...

Never had one clog.

I use a 6 gallon better bottle with 5.5 gallins in it or 6.5 gallon bucket with 6 gallons.

Cathedral said:

People who should not try this:
Forrest Gump
Grandmas and/or Grandpas
Delicate kittens
Zombies w/o hands

Click to expand...

Watch what ya say ya young wippersnapper!:rockin:

adamc said:

Never had one clog.

I use a 6 gallon better bottle with 5.5 gallins in it or 6.5 gallon bucket with 6 gallons.

Click to expand...

Same here. 5gal glass, 6 gal glass, and 3 6gal BB's. Never once had an issue. At worst, it gets "restricted" to where large clusters of bubbles come out at once, but I've never once had it actually clog up and blow up or anything.

Just fermented a 1.087 IPA, and it was going nuts with blowoff, but never once clogged.

You can also drill bungs using a metal tube of the appropriate size...just sharpen the edge with a dremel.