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General Category => Kegging and Bottling => Topic started by: ndcube on June 23, 2010, 09:27:16 PM

Title: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 23, 2010, 09:27:16 PM
I'm trying to carb a beer to 25 PSI at 43F.

With a 20' x 3/16" line it was still coming out too fast and I was getting half foam.

I dropped 3 of those things in the dip tube and now it's coming up ALL foam.

Can you put the mixer(s) in backwards? Is there another trick?  Maybe I just have to wait a while after depressurizing the keg?
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: weithman5 on June 23, 2010, 09:43:44 PM
i don't know about the mixers in general, but i have been wondering about a different solution.  is there any reason a separate throttle valve can't be installed close to the keg. this can be used to create a more significant pressure drop near the tank, allowing the flow to become more normalized as you pour.  i suppose a pressure reducing orifice could be put in the line as well. the pressure will equlize slowly between pours but as soon as the pour starts it should drop quickly
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: MDixon on June 23, 2010, 10:25:57 PM
If you are not balanced (too short or too long) then you can get foam.

I'd suggest you know with 100% certainty the keg is carbonated to 25psi and then serve at 25psi with 3/16" beer dispensing hose and you should need in the neighborhood of 8-9' of hose.

Sounds like you definitely have too much hose for either the epoxy doohicky or just using hose.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 23, 2010, 11:34:45 PM
I think I have something else going on.  I tried it again w/o the epoxy mixers and the same line and it was all foam again.

I tested the mixer with just water and it definetely seems to be working.  I didn't see any turbulence in the water coming out.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: MDixon on June 23, 2010, 11:41:23 PM
Your line is too long!

Water has no reason/ability to foam.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: aluminumpark on June 24, 2010, 05:06:17 PM
I'm trying to carb a beer to 25 PSI at 43F.

I think thats more likely to be the problem  are you also serving at 25 psi?  most people serve around 10-15, and thats about the right pressure for normal carbonation at around 40 degrees

at 25 lbs, as soon as the beer leaves that pressure, its going to realease a lot of co2 and cause foaming regardless of how slowly you can pour it
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 24, 2010, 06:48:48 PM
I realize water won't foam but I wanted to see if I was getting any gas bubbles like if my dip tube wasn't sealing properly but I don't think that's the case.

I was hoping to keg some Belgian's. That's why the high carbonation but I may just end up bottling them.

I think the mixer may yet do the trick.  The beer was probably carbed closer to 20psi.  After letting it set 20psi is about when gas started hissing while I turned up the regulator so I left it there and after sitting another 12 hours the carbonation was alot better with 1 stick and a 10' line.

I think my problem was agitating the keg yesterday and letting everything get too warm while I was working on it along with the regulator being up to high.

I'll do some more testing and maybe turn the regulator up and wait a couple weeks to see what happens.

Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: MDixon on June 24, 2010, 10:17:29 PM
Maybe third time's the charm... ;)
Your line is too long

1 - keg needs to be properly chilled and fully carbonated
2 - set the pressure to dispense at the carbonation pressure
3 - set the line length to the pressure

25psi = 8-9' of 3/16" beer dispensing hose

My suggestion -
1 - chill the beer to 43F
2 - carbonate to 25psi (if that is the desired level)
3 - dispense at 25psi (if that is where you carbonated to)
4 - remove the epoxy thingamajig and set the line length to what it should be

Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 24, 2010, 10:30:00 PM
Ha.  Sorry.  I wasn't ignoring your advise.  I just like playing around.

How did you arrive at 8-9'?
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: pjj2ba on June 25, 2010, 04:38:07 AM
I'm glad to see epoxy mixer use spreading.  The epoxy mixers should work, so the problem must be elsewhere,  There was a recent thread on another forum where people were having unsolvable foam problems.  Someone finally noticed that the bubbles were forming at the disconnect.  On closer inspection they noticed a flaw in the opening of the disconnect itself, that was results in extra turbulence, and foam.  Someone else noticed the same thing on their foamy tap.  Looks like it might have been a production issue.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: MDixon on June 25, 2010, 11:33:25 AM
The resistance value of 3/16" is ~3psi/ft, simply divide the pressure by that value and it will yield the approx length of hose required to balance the system.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: dak0415 on June 25, 2010, 01:01:19 PM
Does anyone have the McMaster part # for those mixers?
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 25, 2010, 01:04:38 PM
Does anyone have the McMaster part # for those mixers?

This is what I ordered.
74695A58

Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 25, 2010, 01:11:52 PM
The resistance value of 3/16" is ~3psi/ft, simply divide the pressure by that value and it will yield the approx length of hose required to balance the system.

I'm not so sure about that.

My 5 ft line works pretty perfect at 10psi (w/o a mixer) which would mean it's closer to a 2psi per foot drop.  That is the value that I've seen most oftern during my searching.

I've also read that as you get in the upper psi range like around 30 the drop is < 1.  In other words the tubing resistence isn't constant with pressure.

Have you ever carbed a beer to 25psi and served it w/ 8-9' lines?
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: nyakavt on June 25, 2010, 01:51:56 PM
The resistance value of 3/16" is ~3psi/ft, simply divide the pressure by that value and it will yield the approx length of hose required to balance the system.

I'm not so sure about that.

My 5 ft line works pretty perfect at 10psi (w/o a mixer) which would mean it's closer to a 2psi per foot drop.  That is the value that I've seen most oftern during my searching.

I've also read that as you get in the upper psi range like around 30 the drop is < 1.  In other words the tubing resistence isn't constant with pressure.

Have you ever carbed a beer to 25psi and served it w/ 8-9' lines?


I agree, I've used lines that were much longer than necessary and it doesn't cause excessive foam, just a very slow pour.  You can see the difference if you hook up a long line and a short line back to back on the same keg.  The resistance of tubing is not a static value, it changes based on the flow rate.  If you pour slowly at say 80 oz/min the resistance is closer to .94 psi/ft, whereas a very fast pour of 192 oz/min would be more like 4.7 psi/ft (see this guide (http://www.pjmuth.org/beerstuff/images/Kegging.pdf) from the inventer of Ventmatic faucets (thanks to P-J for sharing this). 

When balancing a system you need to pour slowly enough so that carbonation does not come out of solution, and have enough resistance in the line to dissipate all the pressure at the regulator.  So a high carb beer hits you twice, first you need a long line to dissipate all the pressure at the regulator, and you need to pour slower so the resistance of your tubing decreases, necessitating an even longer line.  To avoid having 20+ foot lines, looks like the mixing nozzle is the way to go.

Another thing that can cause foaming is a clogged dip tube or a perforated dip tube, which sometimes happens if they crack.  Sounds like you got it sorted out though.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 25, 2010, 02:24:20 PM
Sounds like you got it sorted out though.

I'm still working on it but I think I'm getting closer..  Right now I have it set with 1 stick and a 10' line at 25psi.  We'll see how things check out when I get home today.

I'm going to test flow with different numbers of sticks in the dip tub on a keg of water.

Could the stick be causing a clog?  I killed most of the pressure in the keg last night and did a test pour.  It was perfect.  Spritzy with no foam so I dont' think I'm getting a clog.

That's leading me to two conclusions:
1) I need to wait until the beer is carbed the same as the dispensing pressure as has been said.
2) I need to slow the flow down even more.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: MDixon on June 25, 2010, 06:32:01 PM
I've pretty much always calculated using 2psi/ft, but Micromatic states it is 3psi/ft http://www.micromatic.com/direct-draw-draft-beer-system-aid-121.html and the Brewer's Association (read as AHA) states the same http://draughtquality.org/f/ch5.pdf

Personally I've seen all sorts of numbers, 2 is certainly safe and a number I've used in the past...
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: wilypig on June 29, 2010, 01:24:04 AM
Ok I don't understand how to use the epoxy mixer tip to reduce foaming. I do not have any issues but I always like to find new trick to help people in times of need. I would also like to try the trick just to see how it works.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on June 29, 2010, 01:24:21 PM
This is the link that turned me on to it:

http://www.homebrewtalk.com/f35/cure-your-short-hose-troubles-100151/

Seems to be working for me as far as the slow pour but it still seems to depend on the type of glass and it's temp as to how much foaming I get at that pressure (as has been said).

Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: bdgrfrisch on September 04, 2010, 04:09:10 PM
Is there a formula/ratio of how many of the epoxy mixers to use to compensate for a certain pressure level? ???
You know, 15 psi @ 38F with 3 mixers requires "X" feet of 3/16" line.
Or is everybody just using trial and error to see what works?

Cheers........
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: jptheelder on September 05, 2010, 01:51:09 AM
[quote author=MDixon link=topic=2629.msg30344#msg30344 date=1277465605]
The resistance value of 3/16" is ~3psi/ft, simply divide the pressure by that value and it will yield the approx length of hose required to balance the system.
[/quote]


Do you buy/make a new tap line for each beer you serve? Is there a happy medium to look for as I replace them, or should I have a reel of line and cut a new one for each beer? I have always just got the ones already assembled in the past.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: tschmidlin on September 05, 2010, 05:38:38 AM
Most of my beers are served at similar pressures, but I have longer ones for higher carbonated beers.  You can save them in between batches.

FWIW, I think the 3 psi rule to be way off, my 3/16" hose is more like 2 psi or less.  Until you get a feel for it, you're better off starting long and cutting to fit, you can't really add hose easily if your line is too short.  YMMV
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: gordonstrong on September 06, 2010, 01:33:02 PM
If your line is too short, you can bend it or put a clamp on it to increase the resistence, or raise the point of dispense relative to the source.  It's better to have it the right length, but that's a quick way to troubleshoot your line if that's all you have at the moment.
Title: Re: Epoxy Mixers in the Dip Tube ?
Post by: ndcube on September 10, 2010, 11:36:40 PM
Is there a formula/ratio of how many of the epoxy mixers to use to compensate for a certain pressure level? ???
You know, 15 psi @ 38F with 3 mixers requires "X" feet of 3/16" line.
Or is everybody just using trial and error to see what works?

Cheers........

Trial and error for me.  At 44F and 25-30PSI...  4 mixers in the dip tube w/ 10' of 3/16" line has been working pretty well on my Belgians.