Our DIY carbonator is going to be very simple. We just need a tank to store our carbonating target that is capable of being pressurized to about 100 PSI. Rich Faulhaber over at Evil Mad Scientist Labs was nice enough to share the idea of using a water filter housing. Check out www.evilmadscientist.com/article.php/co2inator to see how he did it. Follow on to the next steps to see my take on it.
Step 1: The CO2 Tank
The remote supply line makes this setup easy. One side screws onto the tank and the other usually has a quick connect system. I couldn't find fittings that would adapt the quick connect to the plumbing fittings on the water filter housing, so I just cut the paintball quick connect fastener off. With that out of the way, just use a barb fitting and a standard air compressor quick connect fitting to make things work with the water filter housing.
Be sure to use teflon tape on the threads of all connections to prevent leaks!