How to set up your own filling station:

What you will need: 
- "fill station" which includes: (in this order)
  - female tank connector
  - on/off valve
  - female tank connector
  - adapter that pushes in the tank pin
- bulk tank (20 lbs or more)
  - must have a "siphon tube" type valve or it will not work
- scale
  - must weigh at least 3 lbs and be accurate to the ounce
  - a simple balance can be substituted.  9 pennies held with a bit
    of masking tape equals 1 ounce


Put the fill station on the tank
weigh/balance the tank empty.  Be sure any cap is aready removed.  It is
  not necessary to remove butt plates or tank covers.
Screw a CA tank onto the station
Close the station valve
open the bulk tank valve
wait 10 seconds
(some "tink" noises will be heard)
(don't hold tank while it is filling -- body heat will vaporize the CO2
 faster than it can fill)
close bulk valve
unscrew the CA tank a few turns so pin is released, but seal is not broken.
open statopn valve
(some gas will veynt -- be careful, it's c-c-cold)
remove CA tank
weigh or balance tank
vent excess until you get exactly the limit of the tank
if you are getting too little, try chilling the CA tank in the freezer
   for 30-60 minutes prior to filling, or fill the tank and vent it,
   and then re-fill. (CA tanks get COLD when you vent them!)

Don't vent a tank repeatedly, as it will get TOO cold to safely handle,
and dry CO2 will clog the pin valve and fill station valve.  It will also
*ice up*, drawing water right out of the air!

Wearing gloves is probably not a bad idea.  If CO2 gets vented on your
hands, you will not like it.  Also, grabbing a tank you have just vented
could give you a new experience in frostbite.  Be careful.

I find I can get as much as 10 oz in a 7 oz tank without venting or
chilling.  Be sure to not overfill, as you will be unpleasantly suprised
when the burst disc goes. (even MORE suprised if the burst disc DOESN'T
go, and the TANK GOES.  ouch.)