Relative humidity is simply a fancy term for measuring moisture in the air. If you look out the window and it’s pouring rain, well, that’s 100% relative humidity. On the other end of the spectrum, fire up an empty kitchen oven to 450 degrees for an hour, and you’ll get close to zero moisture.
Guitars like to bask in 45% to 55% humidity. The relative humidity in my house right now is a pitiful 24.4%.
Poor guitars, they’d be in dire straits without a moisture plan.
So, what does low humidity do to your beloved acoustic guitar? Brace yourself strum bud:
- String buzz.
- Fretboard shrinkage.
- Fret ends protruding from the edge of the fretboard.
- Sunken top.
- Rattling tuning peg b bushings.
- Loose tuning machine screws.
- Internal bracing breaking free.
- Glue letting loose from bridge, sound hole embellishments, bindings, and more.
- Spider cracking in the finish.
- Cracked guitar top.
As you can see, the damage can be serious and sometimes irreversible. Good news though. Guitars are forgiving creatures, and getting them humidified can be pretty easy.
You could take your guitar to a fancy luthier or repair shop. They’ll happily take your money and solve the humidity issue. Or, you could splurge on fancy humidifiers made from magical moisture-drawing material.
But let’s be real, you’re looking for a safe, budget-friendly solution.
So, let me share with you a secret that won’t break the bank. You can humidify your guitar with a few inexpensive items. Here’s what you’ll need:
- Plastic soap dish (fancy, huh?).
- Kitchen sponge (preferably as thick as the soap dish).
- Ziploc bag.
First things first, let’s focus on internal humidification.
We want to keep your guitar moisturized from the inside out. Here’s what you need to do:
- Slice the top layer of a one-quart Ziploc bag. Fold the bag so it creases in the middle of the top surface. Just make sure the back of the baggie remains flat—no fashion creases for it.
- Grab a pair of scissors and make some slices in the bag’s top surface, about 2 inches away from all edges.
- Keep making those slices about 1.5 inches apart across the top surface of the baggie. Be careful not to cut the backside—no baggie casualties allowed.
- Now, get a thick dishcloth or dish towel and fully saturate it. We want that bad boy soaked to the gills.
- Fold the cloth to a size that will fit snugly into the baggie.
- Gently squeeze the cloth until it’s moist but not dripping excessively. We don’t want a water show inside your guitar.
- Insert the moistened cloth into the baggie and zip it shut.
- Carefully slip the bag into the sound hole of your guitar. Make sure the sliced side is facing the sound hole, not the bottom of the guitar.
- Lay the bag flat on the bottom of your guitar. Those slices will let moisture escape while keeping any damaging moisture from soaking into the wood directly.
Clever, huh? As long as you keep your guitar in its case flat on its back it is. But wait. We’re not done yet.
We also need to humidify the external surface of your guitar.
Don’t worry, it won’t harm the finish. Repeat the same steps as before, but this time, you won’t put the bag inside the guitar’s body. We’re putting the bag in the pick box compartment of your guitar case.
Adjust the baggie size and fold the dishcloth to make it fit snugly. It’s like a little spa retreat for your guitar. If your guitar is really dry and sporting a sunken top, this method should bring it back to life within 72 hours.
Now, let’s talk about moisture maintenance.
After your guitar is up to the right humidity, you’ll want to remove the baggie system above. Leave them in 72-hours max.
- get yourself a plastic soap dish from a local dollar store. You know, the kind with slots or holes in the top. If they don’t have holes, drill your own and sand off any burs.
- Purchase a couple kitchen scrub pads. Cut off the outer scour fabric so all you have are the sponges.
- Moisten the sponges until it reaches that perfect dampness where it won’t drip when lightly held. We’re aiming for just the right moisture level—no sloppy sponges allowed.
- Insert the sponges into the soap dish and put the lid on. You may want to use a rubber band to keep the lid in place.
- Slip the soap dish into your guitar case wherever it fits. You can place it under the head of your guitar or alongside the guitar body. Anywhere it won’t feel pressure.
Just make sure the slotted lid is facing away from the body of your guitar. We don’t want any unexpected moisture surprises.
Voila. Your guitar can now enjoy tropical humidity for a few bucks.