Steve B wrote:
I have a cabin, and this trip, it was COLD up there. I noticed several
major air leaks, which I addressed with gaskets, wiper gaskets, and
weatherstripping.

I saw a program once where they used smoke to detect leaks. They had IIRC a
piece of cotton rope that gave out a wisp of smoke, and this wisp followed
any air flow.

Would I put a good sized fan outside blowing in to create positive pressure
inside, or put it exhausting out to create negative pressure in order to
follow the wisps of smoke and see where to chink and caulk?

Google smoke pencil. The fan is inserted in the doorway/window blowing
out so the smoke gets drawn into the building. If you need to use a
fan you have a pretty tight cabin.

R