Beer Forum

Anybody know what o-ring Jamil was referring to in the latest Brew Strong Kegging podcast?

Here are the specs for the O-Rings, and the McMaster-Carr Part numbers:

(1) Dip Tube O-Rings
5/16" ID x 1/2"OD x 3/32" width
9452K172 BunaN #109
Pkg 100/$1.96

(2) Post O-Rings
7/16" ID x 5/8" OD x 3/32" width
9452K23 BunaN #111
Pkg 100/$2.15

(3) Lid O-Rings
3 1/2" ID x 4" OD x 1/4" width
9452K218 BunaN #417
Pkg 10/$12.69

Those are the round cross section o-rings. I am pretty sure by "double seal" jamil meant the square cross section ones like these:

http://www.mcmaster.com/#o-rings-cord-s ... es/=6tdfll

However he said they should be silicone too. I think he was mistaken as I can not find a supplier for the square cross section (double seal) and silicone, you can have one or the other it seems.

I am about to replace all of mine (and probably most of the poppets too) and I think I am going with buna and square cross section for posts and dip tubes and silicone for the lid.

Either way, once you know the size which is in the post above you can easily find whatever cross section type and material you want on mcmaster.

The dip tube o-rings should be quad o-rings. Other sites might call them double seal. They should be bunaN. Don't use the round or square ones, as they don't seal well and you have to use excessive force on the threads.

The post o-rings should be silicone.

jamilz wrote:The dip tube o-rings should be quad o-rings. Other sites might call them double seal. They should be bunaN. Don't use the round or square ones, as they don't seal well and you have to use excessive force on the threads.

The post o-rings should be silicone.

Well I at least got the quad O-rings for the dip tubes, but I ended up getting buna N O-rings for the posts after seeing that the properties for buna N are much better than silicone for tearing. Figuring the posts were what get the most wear and tear buna-N would be the way to go.....

I also picked up some silicone dip tubes(figured I would try them out as well) and lid O-rings. Are the silicone lid O-rings better in your opinion?

Do any of the LHBS that advertise on the BN carry these?

Does anyone know if McMaster carries these?

For keg lid O rings I use these http://www.williamsbrewing.com/KEG_LID_ ... P58C78.cfm

This rings have a slightly thicker cross section and a little softer than the conventional rings. I find that they seal much better than the regular rings, especially when you have old kegs with lids that have been dropped a few times. Williams is also a BN sponsor.

Wayne