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General Category => Equipment and Software => Topic started by: gmac on December 30, 2010, 06:27:16 PM

Title: Blow off tube
Post by: gmac on December 30, 2010, 06:27:16 PM
Can someone post a picture of how they made a blow-by tube for a glass carboy?  I tried to make a one but fitting I put into the rubber bung was too large and it seemed to expand the rubber too much and it wouldn't stay in the carboy mouth.  I can probably drill out the rubber to make the fitting I have work but is there a better way?
Thanks
Title: Re: Blow off tube
Post by: BrewArk on December 30, 2010, 06:36:14 PM
I just took a three piece air lock apart & attached the tubing to the inside of the air lock.  Easier than posting a pic!
Title: Re: Blow off tube
Post by: gmac on December 30, 2010, 06:42:13 PM
Thanks.  I had a picture in my mind that it needed to be larger diameter (not sure why that would be since things come out the airlock just fine already).  I was working with a bit larger ID tubing that I had.  Does tubing ID matter at all?  Would bigger allow too much krausen to escape?  Am I over thinking this (yes)?
Title: Re: Blow off tube
Post by: denny on December 30, 2010, 06:44:01 PM
You can use (IIRC) 1 1/8" tubing and just put it in the neck of the carboy without using a stopper.
Title: Re: Blow off tube
Post by: theDarkSide on December 30, 2010, 06:45:35 PM
(http://i304.photobucket.com/albums/nn176/stevo155/IMG_3564.jpg)

Mine is a Better Bottle but would work with glass as well.  The vinyl tubing is 1/2" ID.
Title: Re: Blow off tube
Post by: jeffy on December 30, 2010, 06:45:45 PM
Thanks.  I had a picture in my mind that it needed to be larger diameter (not sure why that would be since things come out the airlock just fine already).  I was working with a bit larger ID tubing that I had.  Does tubing ID matter at all?  Would bigger allow too much krausen to escape?  Am I over thinking this (yes)?


I found some clear plastic tubing at home depot that fit snugly into the top of a carboy, but lately I've been adding a few drops of anti-foam stuff to prevent overactive blow-off.
Title: Re: Blow off tube
Post by: oscarvan on January 01, 2011, 04:07:37 PM
I found some clear plastic tubing at home depot that fit snugly into the top of a carboy, but lately I've been adding a few drops of anti-foam stuff to prevent overactive blow-off.

Is there ANY other side effect of the anti foam?
Title: Re: Blow off tube
Post by: jeffy on January 01, 2011, 04:58:04 PM
I found some clear plastic tubing at home depot that fit snugly into the top of a carboy, but lately I've been adding a few drops of anti-foam stuff to prevent overactive blow-off.

Is there ANY other side effect of the anti foam?

I haven't found any negatives in about a year of use in the boil and sometimes in the fermenter.
Title: Re: Blow off tube
Post by: oscarvan on January 02, 2011, 03:55:28 AM
Yes, I was talking about the fermenter...... Does one add it in there? Or in the boil and it carries over?
Title: Re: Blow off tube
Post by: Kaiser on January 02, 2011, 04:48:27 AM
I just checked, and I use 1 1/4 inch OD vinyl tubing. It's easily cleaned with a bottle brush.

I'm a very strong proponent of letting the Krausen blow off to prevent the brown Kraeusen from falling back into the beer. It didn't happen on one of my recent beers and I notice this as a harsh bitterness in the finish.

Kai
Title: Re: Blow off tube
Post by: tom on January 02, 2011, 05:35:04 AM
Kai, have you done any tests or trials of that?
When I started brewing 20 years ago Charlie Papazian recommended it. Now it seems no-one else does.
Title: Re: Blow off tube
Post by: Kaiser on January 02, 2011, 05:49:39 AM
Kai, have you done any tests or trials of that?
When I started brewing 20 years ago Charlie Papazian recommended it. Now it seems no-one else does.

There is a write-up here: Should the Kraeusen fall back into the beer? (http://braukaiser.com/lifetype2/index.php?op=ViewArticle&articleId=134&blogId=1)

Of all the side-by-sides, that I did to evaluate brewing procedure changes, this was one that showed the the most pronounced difference to me. I suggest that brewers give this a try to see if improves their beer.

We also discussed this topic here: http://www.homebrewersassociation.org/forum/index.php?topic=486.0 which includes a link to an old Zymurgy article.

Kai
Title: Re: Blow off tube
Post by: gmac on January 02, 2011, 05:45:01 PM
Thanks, I'll go look for some 1 1/4 OD tubing (or what will fit the hole in my carboy).  I was thinking it would have to be more secure than this to avoid any air and potential bacteria but it appears not.

I used to use a blow-by like the one first mentioned although I cut off the bottom of an airlock and fitted a hose to it.  Worked fine until it got full of hops and blew beer everywhere when the cork let go.  That's why I was wondering what others did and the diameter.
Title: Re: Blow off tube
Post by: Kaiser on January 02, 2011, 06:01:31 PM
Don't worry about contamination too much. I oftentimes don't even have the other end submerged in water for the first few days. As long as it points downward bacteria won't get in.

Kai
Title: Re: Blow off tube
Post by: Slowbrew on January 02, 2011, 11:26:02 PM
I had a broken plastic racking cane lying around, so I cut a short piece of it off and stuck that in a standard bung.  Then I put a short piece of racking tubing on the top end of the cane piece.  Works like a champ and when the major fireworks are done I just remove the cane and insert a 3 piece fermentation lock.

I used to just put a piece of racking tubing on the inner pipe of the airlock but it still plugged up once in a while.  The bootom of the airlocks I've got have a 4 branch screen type thing on them that would get gunked up.

Paul
Title: Re: Blow off tube
Post by: Hokerer on January 03, 2011, 02:48:51 AM
I used to just put a piece of racking tubing on the inner pipe of the airlock but it still plugged up once in a while.  The bootom of the airlocks I've got have a 4 branch screen type thing on them that would get gunked up.

Most folks, when they use that kind of airlock bung, cut out the "4 branch screen type thing" for that very reason.
Title: Re: Blow off tube
Post by: maxieboy on January 04, 2011, 03:39:05 PM
(http://www.donosborn.com/homebrew/blow-off_tube.JPG)

No clogging, exploding, etc.
Title: Re: Blow off tube
Post by: oscarvan on January 04, 2011, 04:14:08 PM
I used to just put a piece of racking tubing on the inner pipe of the airlock but it still plugged up once in a while.  The bootom of the airlocks I've got have a 4 branch screen type thing on them that would get gunked up.

Most folks, when they use that kind of airlock bung, cut out the "4 branch screen type thing" for that very reason.

Hmmmm, GOOD idea.
Title: Re: Blow off tube
Post by: Kit B on January 04, 2011, 05:01:01 PM
(http://www.donosborn.com/homebrew/blow-off_tube.JPG)

No clogging, exploding, etc.


It's the cows.
Title: Re: Blow off tube
Post by: Hydro on January 05, 2011, 04:19:16 AM
Consider using a 6.5 gallon glass carboy as you primary fermentor.
Title: Re: Blow off tube
Post by: gmac on January 06, 2011, 02:14:56 AM
Consider using a 6.5 gallon glass carboy as you primary fermentor.
I think I already do.  Mine is 23 L, which I think is bigger than 5 US gal.  I don't really know.  We went metric when I was in grade 2.  Probably why my OG etc doesn't line up with what people suggest it should be.
Thanks to everyone for all the suggestions.  I really appreciate it.
Title: Re: Blow off tube
Post by: mlager on February 07, 2011, 04:54:27 AM
I just put mine together using two plastic barbs and a brass elbow connection. Stuck it in my thermowell's hole, which did cause it to not stay in the bung as much as I wanted, but use duck tape to make sure its secured into place. By the time everything dries, that stopper isn't going anywhere. I like this approach because it doesn't require any vertical space which is nice in the chest freezer I use to ferment in. Sorry about the picture not being rotated, I'm too lazy to fix and re-upload to web server :)

(http://resources.rock-pond.com/photo.JPG)