Originally Posted by
cyccommute
Gotta disagree. The solvent will only evaporate if the can or tube isn’t closed properly. The can, on the other hand, has no special seal from the factory. It’s filled and shipped in exactly the same condition that it will sit on a bench.
Bottom line: put the cap on properly and the fluid will last for years.
I'm sure you have your process down, but you're the exception. I know you know this, but the volatiles in the can evaporate until the partial pressure of the solvent in the air above the fluid is at saturation. Every time you open the can you let in some fresh air and no matter how well you close it there will be more evaporation into the unsaturated atmosphere. This is a bigger issue the larger the ratio of air to fluid. If you only glue one patch at a time, you're opening the can and refreshing the air with every patch.
My hypothesis: If one can would do 200 patches in a single setting, you would get far fewer patches glued doing one at a time, every two weeks before the stuff was gone. Even worse if you leave the can open during the patching, and even even worse if you do it in warm weather.
I only go through a few of those little tubes per year, so cans don't make any sense for me at all.