I would like to open the discussion again about refilling isobutane canisters because forum posts and other results from Googleing the topic did not focus on specifics of making this as safe a prospect as we can.
There are many excellent articles about stoves, canisters, (exploding!) and ways of thinking out-of-the box safely so refilling might be viable if the process of filling and using is focused on safety.
There are 3 considerations I’m trying to work through: safety during use, hassle, cost savings, if any.
The goal is to carry a single small canister at 3/4 rated capacity so I don’t have to carry 2 canisters, trying to use up the partial one. (I get it – maybe replace my tent or sleeping bag instead)
For safe use of refilled canisters, I would go with butane rich, no propane, use a canister originally designed for cold weather propane rich fuel, and fill only 3/4 of it’s rated capacity. The butane would be lower gas pressure, the canister designed for higher pressures.
Canisters are not sold or designed to be refilled, indicating the Lindal valve has a limited life span. Assume the maximum number of cycles of the valve would be the person using a large 450 gram canister to bring water to a boil. My use is 30 minutes to an hour maybe simmering chunks of beef in a stew. If I replace the small canister every time I empty a large host canister, I should be well within that number of cycles of the Lindal valve. (Roger has stove efficiency charts to get us in the ballpark, but I have not run the numbers yet.)
The canisters again would be butane rich, 3/4 capacity, and not overly used before replacing. Is this really any more dangerous than jumping out of an airplane, driving on the freeway, or commuting via bicycle?


