When someone brings me a guitar that has not been properly humidified I can tell immediately. The signs are always the same. It starts off with action problems and then progresses to excessive bellying around the bridge and caving at the sound hole, sharp fret ends, body cracks, bridge lifting and neck angle problems.
Part of the problem is that when purchasing an acoustic guitar the subject is either not brought up at all or looked over as an attempt by the salesperson to up-sell the customer on something they don’t actually need. The reality is that nothing can cause more problems for your acoustic guitar than improper humidity.
It still thinks it’s a tree…
The reason for this is that in nature trees use the capillary action of the wood to deliver water up through the trunk and branches of the tree. Taking the wood from the tree does not stop this action from occurring. Wood will always absorb the moisture in the atmosphere but if the atmosphere is too dry the water in the wood will begin to evaporate. When wood looses moisture it looses mass and starts to shrink. It also becomes more brittle.
There are many forces and tensions constantly at work on an acoustic guitar. If the top begins to shrink due to lack of humidity it will begin to warp in a very particular way. The sides and bracing will be pulling in one direction while the strings and neck are pulling against them.
The belly will begin to bulge resulting in significantly higher action. Shaving the saddle can be a temporary fix but it won’t address the real problem.
Eventually, radial cracks begin to appear. Under constant string tension the bridge itself starts to tear away from the weakened and brittle top of the guitar. Meanwhile, and almost unnoticeably, the neck angle has shifted below its original position, again contributing to higher action.
While all of these problems can be fixed, they are not cheap. On less valuable guitars it my just not be worth the cost of these repairs. All of this can be avoided though by keeping your guitar properly humidified from the very beginning.
Your guitar wants to be in its case…
The first component to keeping your guitar humidified is a good hard-shell case. A gig bag will not help in any way. The enclosed space of a hard-shell case is much more easy to control than an entire room and it offers protection from physical damage as well.
The next thing you’ll need is a guitar case humidifier. There are many different options available but most of them involve a sponge that you fill with water and hang in the sound hole. These are fine but they require some babysitting. If your guitar and case are dry they can suck up all the water in the sponge in just a single day. The sponge will be dry as if you never added any water to it at all. It can take some time to reach equilibrium so you will need to check and refill the humidifier every day until it retains water. It’s a good idea to keep a small hygrometer in the case as well to monitor the actual humidity.
D’addario/Planet Waves produces a system that is designed to maintain a relative humidity between 45% and 50% at all times without adding any water to your guitar. The D’addario/Planet Waves Two-way Humidification System is a set of three gel filled packs (2 for your sound hole and 1 for your case) that add humidity when it’s too low and eliminate humidity when it’s too high. There’s no guesswork and you simply replace the packets when they get crusty (between two and four months). This is by far my favorite system and the one I recommend above any other.
If you absolutely must…
Many guitar owners like to keep their guitars out of their cases, displayed on stands around their rooms. This is only a good idea if you can assure that the relative humidity in that room stays between 45% and 55%. If you must have your guitars out, purchase a room humidifier and a hygrometer to monitor the humidity.
There is still hope…
If your guitar has been damaged because of improper humidification, all is not lost. Believe it or not just about any damage can be repaired. It really only comes down to cost vs. value. If you need an evaluation for this or any other type of work please give me a call.
Call Today: (682) 207-1706