JR North wrote:

Hmmmm...not sure of the clime where you hang, but up here in Soggy,
Gloomy Seattle ... I have never
had a problem with steel mig wire corroding.

NW of Boston. I have to run a dehumidifier in the shop in summer, but
not too bad. The MIG wire rusted because it was in there a looooooong
time. I can't say exactly, but my first 2 lb spool lasted 2 *years*. I
often have projects that only take a few seconds of arc time.

Bob