how long does finish keep out moisture/humidity?

[birdpointlightstring32]

I just built a heat box but worried about electric bill. lol.. just wondering how long does a proper finish or sealant keep humidity out.

[Pat B]

All the finish does is slows the hygroscopic rate. Your wood bows will all breath and in doing so take on and let out moisture to the atmosphere. Generally during the winter the humidity drops and especially in your home. You don't need to store your bows in a hot box all the time. All of my bows are hanging on pegs. My day to day bows are handy in the sunroom, the rest are in the utility room; the driest room in our house. Also, some woods take on moisture more readily than others because of the amount of natural oils. Use them during the wetter weather.

[mikekeswick]

Not all finishes are equal either, some are much more effective than others. Ipe is superb in a humid environment.

[Springbuck]

  And a wax finish seems to allow water to move slowest, but you can't just wipe it on.  Wax finishes can be a pain to apply, because everything has to be warm and the wax must melt in and be absorbed, not just lie on the surface.

Use your hotbox to get woord to optimual internal moisture content to ensure low set while working toward tiller, but you won't be able to do much about small fluctuations that follow ambient humidity.

[birdpointlightstring32]

One more question and I will get out of your way today. lol.  what woods take the least set in high humidity?

[Pat B]

The one you overstress the least. 

[PatM]

I have seen numbers suggesting that Ipe is at its strongest at 12% moisture.
 Many of the resin rich woods are more impervious to moisture or less affected by it.
 This is part of the reason why Yew has its reputation in England.

[George Tsoukalas]

I'll answer in a different way. Of the woods I've used,  osage, black locust and maybe hop hornbeam are the least affected by high humidity. I haven't made that many from hop h.  Jawge