I have had some problems with rust on my tools (tablesaur, jointer) in my shop in the last couple of springs during the rainy damp season. So this year, I picked up a used dehumidifier for $20 (it even works!) Today I bought a digital temp/hygrometer from the hardware store and it said my rh was around 77%. I let the dehumidifier run for a few hours and it is down to about 60%.
So the question is, what do you try to keep your shop at? In the latest issue of FWW, there is an article on wood (go figure) and a graph comparing moisture content to relative humidity. It looks like a rh of around 50% will keep lumber at around 8-9% or so. I was thinking this would be a good benchmark to shoot for.
So, what do you all do? I know some of you live in climates much more humid than Michigan.
Frank