Re: Effect of AC to noon day in Arizona mando?
This is a very difficult problem. Exposing a good instrument to extreme variations in temperature and humidity, which is what'll happen when you pull it out of its controlled environment, can result in near-immediate effects.
You might consider getting a carbon-fiber mandolin, which is an expensive solution, but can give you a degree of invulnerability to environmental variations. The opposite solution is to get a thickly-finished, laminated-wood "beater," which won't sound as good or play as nicely, but has the dual advantages (?) of being less susceptible to temperature-humidity change, and less expensive if it does sustain damage.
Sounds like you're doing the best you can, but there's really no complete protection from high heat, extreme dryness, and the inevitable effects of changing from A/C to desert temperatures. Good luck.
Gibsn: '54 F5 3pt F2 A-N Custm K1 m'cello
Natl Triolian Dobro mando
Victoria b-back Merrill alumnm b-back
Stradolin Vega banjolin
Sobell'dola Washburn b-back'dola
Eastmn: 615'dola 805 m'cello
Flatiron 3K OM