DIY inexpensive SS flow restrictor to solve foam problems.

[ODI3]

Hi Everyone,

I have been interested in using kegs but have hated using the long beer lines to add resistance to get a nice slow flow. I noticed the swizzlestick plastic keg insert, but wanted something SS.

Basically, its a size 13 (I think) 4 inch machine screw with the head half cut off.
The idea is to insert it into the bottom of the dip tube when the keg is empty. Just flip the keg over, install the dip tube and put the screw into the tip tube before you push the tube up into the keg. (the half-head prevents it from sliding up the liquid tube but restricts the flow. The more of the head you cut off, the more flow you get. So far, it works great with water and beer with half of the head cut off. I have tried from 8 to 20 psi and the water/beer always flows nice with same flow.

My main post about it is on my blog:http://www.londonbrewers.ca/blog

Try it out, let me know what you think!

 

[Stealthcruiser]

Not a machine screw, but whatever works, works!

Me likey!

 

[FalconsBrew]

This is very interesting... Might try that when this keg is kicked.

 

[Monster Mash]

The restriction is only at the head so it won't really solve the problem of Co2 coming out of solution at high pressure. If the beer had to go through the threads you would get better restriction but it would never seal in the dip tube.

 

[ODI3]

It is possible to use a one size larger screw, but then you almost have to screw it in to the tube. I thought It might cause the tube to rust due to scratching off the pacified layer. It fits quite snug. With this size, I think it offers too much restriction, although I haven't tried it after cutting the head half off yet.

 

[ODI3]

Hi Monster Mash, I have been thinking about your comment. I think you are right that some of the co2 does come out of solution, But I am not sure how much. I am going to run through a few kegs to get a better feel for how well the screws work. (Ya I know, Science is hard work but someone has gotta do it!) Currently I am running my keg at 10 PSI and 40 deg F with a standard 100% Pils recipe, mash at 152 ibu 20. I would say that the pour is reasonably fast (definitely not slow) and I end up with a finger width head after filling up 500ml, But, the beer is slightly on the undercarbonated side. (only a few bubbles rising) The keg has been carbonating for 6 days and it is 1/2 empty. I did not use the shake method.

I am also going to try a few other screw cuts, like only 20% of the top cut off, etc. I know 6 days is pretty light on the time it takes to carbonate, but beer seems to go quickly at my house.

At the end of the day, I would be happy if the screw knocked some of the co2 out of solution but I was able to offset it by increasing the psi and/or lowering the temp so that the beer would still be carbonated in the glass.

Ill post my results as I go, thanks for your comments!!

 

[theQ]

...
I end up with a finger width head after filling up 500ml, But, the beer is slightly on the undercarbonated side.
...

So is the beer undercarbonated because of the screw ? what's the higher psi you ever used this at ? what is that does the trick is it the cut screw head or the threads ?!

 

[acidrain]

It's gonna rust where you ground down the head. Needs to be passivated/polished.
Might make a little rust spot on your keg too.
Good idea though.

 

[theQ]

Is the screw going to move up and down into the dip stick corroding it ? The dip sticks are not SS are they ?

 

[day_trippr]

Standard cornelius style keg dip tubes are in fact stainless steel...

Cheers!