wrote in message
oups.com...
Hey, folks. I refill the small 1 lb coleman cylinders all the time.
Harbor freight sells an adapter you screw onto your warm (60 - 70 F)
20lb cylinder.
Put an EMPTY 1lb into the freezer overnight.
Screw the bottle on the adapter connected to the 20lb.
Flip this assembly upside down THEN open the valve for 1 minute.
Close valve, THEN put assembly right side up.
Remove 1 lb. You will get a poof of gas as the safety tube in the 20lb
purges.

I fill CO2 tanks for paintball the same way. Sometimes I skip the freezer
part, and just put a couple ounces of CO2 in the small tank, then let it
vent. That cools the tank very well. Of course, I wouldn't recommend that
for propane.

You really should be using scales when you fill your tanks. It is quite
possible to overfill them the way you're doing it. Remember, as your tank
warms up, the pressure inside increases.