The low flash point of spray is more than likely coming from vehicle used
for spray. As for 3-in-1 oil, I heard there is nothing predictable in that,
they just put any old thing that is at hand; stuff is intended for household
use. A lubrication guy, who is also on Tecscope group, was saying that most
of content of 3-in-1 is vegetable oil. Those oils oxidize easily in air,
what leads to gumming up and higher temperature just speeds up the process.
Regards
Miroslav Pokorni