DIY CO2 - Sealing Airline to Pop-Bottle Top

[Saltcreep]

I know that sealing the airline to the bottle top is one of the biggest headaches in this project. I was just in the HD plumbing section and spotted this. The bard end is a perfect fit for the airline, and the coupler should screw down nice and tight on the inside of the cap. Sticks way out so it should be easy to get a wrench on. The barb fitting is tapered so you have to use quite a bit of torque on the wrench, but it works. On the off chance that it won't fit down the neck of the bottle, I've got another PETE bottle I can use with a bigger cap.

[fischkopp]

Sealing isn't really a big deal since the pop bottle is never under pressure. Simply drill a hole into the bottle cap that is smaller than the air hose, fiddle the hose in and you are good to go. You can smear some silicon around it if you like.

[magnosis]

Nice find, Saltcreep !

I did it he fischkopp way when I started with DIY CO2, and ended up losing most of the CO2 through that hole.   That was because I used check valves and a diffuser that didn't pull (it actually required some pressure from the CO2 line)

I think it depends what kind of reactor / diffuser he's using;  on a venturi loop, that would be a non-issue.  But on a setup like I had, it needed to be sealed very tight, because there WAS pressure building in the pop bottle.  I ended up using marine glue to seal it tight.  Then I got tired of mixing yeast and sugar and making a big mess all the time, and in came the pressurized system

[Saltcreep]

Nice find, Saltcreep !

I did it he fischkopp way when I started with DIY CO2, and ended up losing most of the CO2 through that hole.   That was because I used check valves and a diffuser that didn't pull (it actually required some pressure from the CO2 line)

I think it depends what kind of reactor / diffuser he's using;  on a venturi loop, that would be a non-issue.  But on a setup like I had, it needed to be sealed very tight, because there WAS pressure building in the pop bottle.  I ended up using marine glue to seal it tight.  Then I got tired of mixing yeast and sugar and making a big mess all the time, and in came the pressurized system

Thanks, It works like a charm. I figure there has to some pressure in there; I'm getting a constant stream of micro-bubbles out of the 3" or so of the Limewood. I expect I'll be picking your brain, and others, on that other issue sooner rather than later. It will have to wait until I'm done my travelling though, probably middle of April.

[charlie]

I think what fischkppp was trying to convey  is that with DIY co2 generator ( pop bottle) a friction seal ( smaller hole than tubing) will work in most cases, however in my experience they are times when the initial co2 generation start upt he pressure can be somewhat high.
I have in the past used plastic fuel bulkheads for remote model aircraft, these use to  be found @ Dynamic Hobbies & they worked great.
http://dynamichobbies.com/contact/

[garnpet]

The plastic fuel bulkhead in action...