Climate controlled room - time to acclimate wood?

[Daniel P]

Testing over the past few months with a hygrometer has shown that we're often in the 75% range here at my house in the Pacific NW - higher that what most would recommend for storing tone woods. So I've just set up a large closet with a dehumidifier to bring the humidity down to 45-50% for storing my wood.

I've put the top, back and bracing material for my next guitar in the closet, and wondering if there is a general rule of thumb for how long it takes dimensioned wood to acclimate to the lower humidity? Give it a few days, weeks, ?...

For instruments that will stay here in the NW, would I be better not to go too low on my pre-build humidity - maybe more like 55%? Or am I starting to overthink it.

[Daniel P]

In less than 45 minutes at 40% humidity the processed sitka top really had bowed - the outer edges were curled up about 1.5" from the center.

I've adjusted the dehumidifier to aim for 50% and suspended the top in the closet so that it will dry more equally on both sides, and is straightening out quickly. The back plate did not bow nearly as much.

[John Link]

I sticker newly arrived wood under clamped pressure.

[Daniel P]

John- yes, all my new unjoined soundboards are stacked, under pressure - I likely should have done the same with this fully processed top (thickness, rosette in, and sound hole cut).