Just to follow up on a PM request. Here is my very simple budget charger build.
Charger Parts List & links:
GI Keg Charger
$20 @ LHBS / online for less
1/4" MFL to 1/4" MPT fitting
from LHBS or $2.39 @ midwest
1/4" Hose barb swivel nut
from LHBS or $1.29 @ midwest
approx 2' Vinyl Tubing Braided, 1/4" ID x 1/2" OD @ Home Depot/Lowes etc
(2) 1/2" hose clamps (optional)
Valve extension Chuck (optional)
Teflon Tape (not required*)
DIY carbonator cap:
Metal Tire Stem
PET soda bottle and original cap
Tire stem tool
Basic Charger Build:
1.) Teflon tape* and Screw the 1/4 MFL x 1/4 MPT fitting into the GI Keg Charger
2.) Teflon tape* and Screw the hose barb onto the other end of the MFL/MPT
3.) Cut approximately 2' section of 1/4" ID braided vinyl hose and push on to the barb,
4.) Slip a 1/2" hose clamp over the barb and tighten
You now have a basic CO2 charger once you install a 16g food grade cartridge according to the GI directions. Yeah, it's that easy.
Basic DIY carbonator cap: Credit http://www.truetex.com/carbonation.htm
1.) Discard all the rubber gaskets from the tire valve.
2.) Use the stem tool to remove the interior valve assembly
3.) Drill a 3/16"(? confirm size - match stem) hole in the bottle lid. Leave the interior soft plastic gasket.
4.) Insert the stem from the inside of the cap and place the washer and nut on the outside. Hand tighten + 1/2 turn
You've now got a fully operational deathstar. Er, Carbonator.
Basic force carbing instructions
1.) Fill bottle with liquid to be carbed to original soda height and chill. You can play with water.
2.) Screw the cap on. Warm the free end of the vinyl tube under hot water and "thread" on the end of the tire stem. Tighten the second optional hose clamp or make the optional chuck.
3.) Loosen the cap slightly and squeeze the air out. Retighten lid
4.) Give a short burst of the GI trigger.
5.) Shake. The bottle should shrink and relax.
6.) Repeat the co2 blast about 3 times total per 1/2 liter.
7.) Uncap and enjoy.
Refer to the bottom of this for instructions
on how to make the screw on chuck.
Hope that helps.