: Hey, I bought my wife a creme brulee torch years ago that she used
: once. I know it's butane, but maybe that would work, too? It's a
: little more maneuverable than a propane torch.

GG is set off by humidity. It doesn't need a lot, it is not necessary to apply liquid water to one surface, just breathing on it will trigger setting.

Propane gas and inverting the bottle both work well in my experience, and squeezing the air out of the bottle should work too although I haven't tried it. Cold air is very dry: holding the bottle in a freezer or fridge and squeezing it a few times should expel enough humidity to prevent - or at least delay - setting in the bottle.

I don't think Butane would work as well as Propane because it is lighter than air and will not "pour" into the bottle the way Propane does.

If the trick with the thinners doesn't interfere with the chemistry, then I imagine it can be left in the bottle since it will be inverted to apply the GG . . .