Yeah this is a nice idea. But just go and build a well sealed display case. Use any material you want.

Just the fact that the guitar is in a sealed case would be enough to keep it stable, better than any run of the mill guitar case.

Use a good hygrometer and hang some damp-its in there. Taylor highly recommends the use of the damp-its system, because they really work! Your guitar won't take more moisture from them than it needs.

If the guitar doesn't go out to work very often, you'd be all set with a sealed display case, damp-its, hygrometer and a larger humidifier for your room (its good for your health too, but I know , the guitar is more important :P .
If the guitar does go out to work, then I'd prefer to allow some reasonable seasonal changes and keep the guitar adjusted for them. It might damage the instrument more, not to mention be a little annoying to have it stored at 50% relative humidity, then spend eight hours or more in a drastically different environment experiencing changes while you try and play it.

Sam, go for it and show us you work!

Tommy P. wrote: Yeah this is a nice idea. But just go and build a well sealed display case. Use any material you want.

Just the fact that the guitar is in a sealed case would be enough to keep it stable, better than any run of the mill guitar case.

Use a good hygrometer and hang some damp-its in there. Taylor highly recommends the use of the damp-its system, because they really work! Your guitar won't take more moisture from them than it needs.

If the guitar doesn't go out to work very often, you'd be all set with a sealed display case, damp-its, hygrometer and a larger humidifier for your room (its good for your health too, but I know , the guitar is more important :P .

If the guitar does go out to work, then I'd prefer to allow some reasonable seasonal changes and keep the guitar adjusted for them. It might damage the instrument more, not to mention be a little annoying to have it stored at 50% relative humidity, then spend eight hours or more in a drastically different environment experiencing changes while you try and play it.

Sam, go for it and show us you work!

So what rh would you suggest I keep the case at? 60%?

also are you sure that my guitar cant get too wet and swell? (I currently am in arround 70% humidity and I have dramatic humidity changes in my area)
If I were to have the outside sealed and the inside UNSEALED, would the case itself absorb excess moisture (a soft wood such as pine) instead of my guitar?

Good question. I'd remove as many variables as I could, seal all framing woods in and out of the case and install a gasket on the door. Let the damp-its do thier thing, they'll regulate better by design.
No, I wouldn't go as high as 60% rh, maybe 55% tops.
I've suffered, and seen others suffer with rapidly changing guitars, and IMH experience its best to stay ahead in small increments. Sun, stage lights but worst of all high humidity are toughest to deal with.

Sam, the scope of this project will go well beyond my ability to make scientific recommendations. I don't have data to support the differences of the effects on an instrument, eg; rate of absorption from an increase/decrease @ specific temp/rh to specific temp/rh with other variables such as wood type and finish type.

But as 72F @ 50% relative humidity is recommended by Martin, I think that would be the way to go.

I do know from experience the rate of absorption is non linear depending on how dry or hydrated the wood is. I also know that rapid changes cause the most severe damage at worst, and at best cause playing and setup problems. Dry wood shrinks and cracks, and overly moist wood bows and warps. Heat messes with the glues.

" I do know from experience the rate of absorption is non linear depending on how dry or hydrated the wood is."

Does this mean that the rate that the guitar absorbs humidity from the dampits, and the ammount of water it absorbes depends on the ammount of water the guitar has in it?, even if I have too many dampits in the case?

So putting a whole bunch of dampits (more than nessescary) in the case would not release too much water for the guitar? Do the dampits only release more water if the humidity is lower than 50 and the guitar is sucking moisture in? do dampits stop releasing water when the humidity is at 50%.

Or does the guitar just keep absorbing the humidity, and putting too many dampits in my case would result in too great of a humidity?
Thanks for the help.
-Sam

Does this mean that the rate that the guitar absorbs humidity from the dampits, and the ammount of water it absorbes depends on the ammount of water the guitar has in it?, even if I have too many dampits in the case?

Too many dampits can damage the instrument if it is already perfectly moisture balanced. And they must be wringed out very well when put to use properly. Its in the instructions. It's a common mistake not to wring the dampit well, and may be why some luthiers ( not Taylor, they absolutley recommend them) get silly and frighten thier customers into not using them. Its something they share with law enforcement officers-that is-only seeing the bad and not the good. Its irresponsible of them(the luthiers). Not everyone, especially journeyman players, have the luxury of climate controlled rooms for storage.

So putting a whole bunch of dampits (more than nessescary) in the case would not release too much water for the guitar? Do the dampits only release more water if the humidity is lower than 50 and the guitar is sucking moisture in? do dampits stop releasing water when the humidity is at 50%.

Dampits will, if they have to, release all the moisture they have to the guitar wood. If you were to rely on unsealed interior case wood to release moisture to a dry guitar, it would be more like "water finding its own level" kind of a thing. Both woods would retain equal amounts of moisture.

Or does the guitar just keep absorbing the humidity, and putting too many dampits in my case would result in too great of a humidity?
Thanks for the help.

Yes, too much is a bad thing. Really, don't overuse them. Get a digital hygrometer, and you'll see how easy it all is. Actually, the prices on those cases are resonable. The curio types are nicer than the wall hangers though IMHO. Gotta be clumsy getting them in and out in a hurry too, and they're not lined in felt-ouch.

Funny thing, cheap guitars are not as much of a problem. But then again, their lack of delicacy translates to lack of beautiful vibration.

We're both in similar climate zones and get to experience all extreme types of weather. Spring is very humid, and I start watching just as closley as I do in the more damaging dry winter months when we turn up our heating in our homes.
I have two of Sears largest humidifiers for the winter, and sometimes need to refill the 13 gallon reservoirs daily during winter maintaining 73F @ 50% rh. not to mention $500 month heating the place last year!
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