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DIY CO2 Reactor CO2 inlet question

2071 Views 4 Replies 5 Participants Last post by  chagovatoloco
(I couldn't find a good way to word that title) :confused:

I've seen a couple in-line DIY CO2 reactor builds where they use plastic airline connectors on the side of the reactor, but I also just saw Rex Grigg's instructions ( ) where he just drills a slightly-smaller-than-airline hole and shoves the airline through. Seems easier, and actually more reliable than gluing a little plastic connector on. Seems to me it would take more pressure to force the whole airline out of that hole than to force out a little connector. Do many of you run your reactors like this? Any problems? Would I be justified in spreading a little epoxy or silicone around the airline just to be extra safe?

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I purchased a reactor from Rex, with the CO2 tubing shoved through a small hole into the side. It has held for going on two years now, with absolutely no problems or leaks.

Two things, the tubing is a thick walled CO2 resistant tubing, not airline tubing. Also, the hole is significantly smaller than the tubing. So, use a quality tubing, and put it through the smallest hole possible, and you shouldn't have any problems.
the reason Rex does that is b/c it can be hard to glue things to plastic/pvc, most drill and tap a fitting which also is hard to do on a rounded surface.
On mine I picked up a 1/8th barbed fitting with a 1/8th NPT thread and taped the cap.

Worse case you can simply replace the fitting and use a teflon tale to seal it...

I do not like the glue thing. To me it is halfass no offence to rex. It is very easy to drill and tap. At most elbows there is a flat spot just drill with a letter R bit and tap it with a 1/8 npt tap. If you want to be precise take a center punch or an old nail and hit it in the center of where you want to drill. This will work to center a small drill bit (say 1/16th or so) on the spot you want to place the fitting. Simply drill the pilot and then drill with the letter "R" bit. Taping is simple just start slowly and go until you get just thought the pvc pipe. DO NOT RUN THE TAP ALL THE WAY THOUGH. Back it out and see if the fitting will start, if it will you are home free. If not tap a little further and try again the threads are tapered so it is supposed to get tighter as you go. Once you get the fitting with a few threads started remove it add some teflon tape and reinstall. This will make the setup with less fittings and very easy to do. You can buy the 1/8 npt to 3/16 barb fitting here.
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