Regulator and C02 cylinder won't mate

[Grizbeard]

So I just bought a Midwest Supplies dual draft kit for my mini fridge conversion. I found a screaming deal locally for a filled 20lb co2 tank ($70) at the local fire extinguisher store. The problem - no matter how hard I try, I can't get the regulator assembly to mate to the threads on the tank. As far as I can tell, they're damn near the same size. Is it possible the cylinder is metric or some other weird configuration? Pics included if they help at all:

Thanks in advance.

 

[Brew-medic]

Won't mate. Hmmm try dimming the lights turn on so light music and ask her about her day......

Some regs use different threading. I have one that you thread counterclockwise to thread on. Also I'm not sure if this is universal but our O2 tanks will only fit O2 regulators.

The brass coupling almost looks like a beer gas coupling. Best bet it just goto a welding supply shop. The guys here don't mind lending me a hand with spare parts, it helps quite a bit when I walk in with a 20 lb tank in one tank and a 24 pack of beer in the other and say. Fill one of these and drain the other

 

[ultravista]

Let us know what the issue is. To Brew-medic's point, did you tried threading in the opposite direction?

 

[Grizbeard]

It's definitely not reversed threaded, and as far as I can see has the same thread pitch. I guess I'll just have to make a trip to Praxair to tomorrow to see what the pro's think - 6-pack in hand

 

[iaefebs]

It looks like the threads on your tank are rounded. My guess it will have to be replaced.

 

[Brew-medic]

Happy screwing. Let us know the out come

 

[Grizbeard]

Went to Praxair this morning and boy were those guys helpful. Apparently once in a blue moon these co2 cylinders show up that have a small extension screwed into the front (see photo). This part threads into the inside of the valve and comes out with an allen wrench. Once removed, my regulator goes on happy snappy. The pros at the shop couldn't tell me where these little extensions come from or what they're used for, but they have to take them off anyway to refill the cylinders.

Hope this helps anyone who might run into this problem in the future !

 

[iaefebs]

Great info grizbeard thanks for posting the follow up.

 

[P-J]

Thanks for the update.

See, even this really old man can learn new stuff.
I've looked at that fitting a bunch of times since you originally posted. Did a bunch of Google searches too. Been scraching my head all along as well (BTW - that hurts as I'm balder than an egg. Getting old sucks but it's better than the alternative.)

Thanks again.

 

[woodstone]

Nice not seeing the same old posts over and over....

Great post. Great info. THANK YOU FOR SHARING!

This will save cursing and a rise in blood pressure if it ever happens to me (or others who read this post) down the road!

Cheers!

 

[JRems]

That peice that was removed was a double sided o ring. With it you don't need a paper or nylon gasket.

 

[CharlesB]

JRems is right. My CO2 tank has one of these as well.

http://www.austinhomebrew.com/product_info.php?products_id=12694

It seems like a good idea, I'll have to see if my regulator fits when I get the rest of my kegging equipment.

 

[ultravista]

For $2.50, the CO2 Leak Stopper is inexpensive.

 

[JRems]

Maybe the op was trying to use a regular gasket and the one screwed on the valve and there weren't enough threads left since there was essentially 2 washers.

 

[Grizbeard]

I had tried to thread them together without the poly washer, and they still wouldn't mate. I think the permanent washer that was previously installed was ever so slightly too large (in diameter) as to keep the threads on the female regulator coupling from sliding over it. However, at the Praxair shop they pulled out another female c02 coupling, and it threaded over the permanent washer just fine. Perhaps the one included with my kit has a slightly smaller tolerance. It's a stretch, but if you look at my original picture you can see that the permanent washer is barely larger than the bare end of the co2 outlet.

 

[Brew-medic]

maybe they are incompatible. forexample a beergas regulator differs from a co2 regulator