Too Humid Is As Bad As Too Dry

This copyrighted post can't legally appear anywhere else.

My regular readers know that I quit my job on October 23, and that, a month later, I decided to return to the music ministry that my wife and I had more than 30 years ago, with the additions of also giving speeches and writing two books.

As such, one of the many things that I’ve had to do a lot of for the past several weeks has been practicing singing and playing (on my 12-string guitar) my original songs.

However, since I spent much of last week finishing the creation of my new ministry Web site, I didn’t spend as much time practicing my songs.

Yesterday, when I finally had time to practice again, I discovered that, instead of being able to play for 2 hours at a time without pain in my left hand’s fingertips, I could only play for about 50 minutes, and the last 10 minutes of that was pretty painful.

At the time, I chalked that up to the fact that my calluses haven’t matured yet.

But I also noticed that the intonation (pitch) of my guitar’s strings wasn’t quite right when I played further down the neck; and that their action (distance from the frets) further down the neck seemed noticeably higher than normal, even though I had adjusted the neck’s internal truss rod perfectly just a few weeks ago, and it appeared to still be perfect.

So, last night, I stayed awake and did some research.

My fear was that maybe my guitar needed an expensive neck reset, to correct the neck’s angle compared to the body of the guitar.

So I found a neck alignment test that was described on several different luthier’s sites.

As the test described, I lay a 24-inch straight edge on my guitar’s frets, parallel to its neck, and looked to see where the end of the straight edge met my guitar’s bridge (the dark wooden part that the strings go into, near the sound hole).

On a Taylor guitar like mine, the end of the straight edge should lay right on top of the bridge. In other words, the tops of the frets and the top of the bridge should be at the exact same level.

Imagine how I felt when I discovered that, on my guitar, the end of the straight edge was about 1/16 of an inch below the top of the bridge, indicating that my guitar probably needed a neck reset.

But then I remembered something: guitars — especially high-quality guitars — are built to very precise tolerances, so they’re especially sensitive to changes in humidity.

Over the years, I’ve seen many horror-story photos of guitars that had big cracks and other major damage, because their owners had failed to keep them properly humidified during dry winter months, so their wood dried out and shrank. That’s why I bought a guitar humidifier and kept it in my guitar’s case every winter when we lived in the Frostbite State.

But, here in the Sunshine State, we don’t have a dryness problem. The only humidity problem we have here is too much humidity.

And it’s been very rainy and humid here lately — and warm enough that we haven’t even used our furnace (which would have dried out the house) yet this winter.

So was it possible that my guitar’s action and intonation problems could be caused by too much humidity?

A few clicks later and I had my answer.

My guitar was built in the climate-controlled Taylor factory at a constant 47% relative humidity. So it was designed to “live” in an environment that’s as close as possible to that optimum relative humidity.

A guitar that lives in conditions that are too humid will absorb too much moisture (remember, wood is porous). And, as it absorbs moisture, its various parts will begin to swell, which can cause all kinds of potentially damaging strains on its parts — the same way that the shrinking wood of a dry guitar can suffer similar damaging strains.

In fact, if it’s left uncorrected for too long, a too-humid guitar can burst its seams or suffer all sorts of other, irreparable damage.

The Taylor Web site describes the types of damage that can occur to a guitar from being in just 60% relative humidity for too long. That’s the highest humidity that they describe — I suspect that they don’t want to depress people by describing the damages that could be caused by even higher levels of humidity.

With that knowledge in mind, I checked the hygrometer that I keep in my guitar case. The last time I looked at it, a couple of weeks ago, it read 50% — perfect.

But when I checked it last night, it said 74%.

That’s right — 14% higher than the 60% humidity that the Taylor Web site had described as potentially damaging to a guitar.

I made several more measurements of my guitar, and confirmed that, as I then suspected, it does not need a neck reset.

Its action is high because its top (the large, flat part that has the sound hole) has absorbed enough moisture that it has swelled up slightly. And, as it raised up, it took the bridge up with it; which caused the bottom end of the strings to raise up; which caused the high action and the intonation to be off, because I’m “tightening” them slightly as I press them down an artificially far distance to the frets.

I immediately turned on our home’s central air conditioning, to dry out the whole house.

And, since I didn’t have any commercial desiccant to put in my guitar case, to dry out my guitar, I poured some of Petey‘s clay kitty litter into a cotton sock, folded its end down, stapled it several times, and slid it into my guitar’s sound hole, before I closed its case.

I finally got to bed at 5:00 AM this morning.

Ninety minutes later, I woke up, to tell my wife about what I had done all night.

Then I went to Walmart and bought a bag of Mimi Litter — a kitty litter that’s 100% silica gel — that tiny gravelly desiccant that you always find in tiny packets in packages of brand new shoes, electronics and many other products.

It absorbs moisture, and then, when it’s “full,” you bake it in the oven to dry it out, and reuse it — over and over.

I bought Mimi Litter because I discovered that silica gel is incredibly expensive if you buy it as a dessicant. Shop around a little, and you’ll quickly see that, even online, it will cost you at least $9 plus shipping, to buy just a few ounces of it.

But, if you go to Walmart and buy a bag of Mimi Litter, you get 4 pounds of silica gel, but it only costs $4.17.

I’m really relieved that I noticed my guitar’s symptoms right away, so it wasn’t overly humid long enough to cause any damage. And, from everything that I read last night, I’m confident that, during the next few days, it’s going to return to the level of relative humidity that it deserves, and its top (and bridge, and strings, and intonation) will return to normal.

It’s happened many times lately, and it’s happening again: I’m running on a total of only 1.5 hours of sleep today.

And I’m loving every minute of it.

Update, January 10, 2012: DON’T USE MIMI LITTER AS A DESICCANT!!! It doesn’t work for that purpose. It works incredibly well if you drop some of it in water, but it doesn’t absorb any moisture out of the air. After nearly 24 hours with a sock-full of Mimi Litter inside of it, the inside of my guitar case was still at 64% humidity — the same level that it had been after I had left it open to the drier room air for awhile before I closed it up yesterday afternoon. When I saw that, I put my hygrometer inside the sealed bag of Mimi Litter for a few minutes — if it was a desiccant, the humidity inside that bag should have been 0%, but my hygrometer said it was 64%.

The reason I thought that Mimi LItter was a desiccant was because it is a Chinese product, and I misunderstood the wording on the Mimi Litter bag. It clearly states that it contains “porous silica sand” not silica gel, but since the product itself is much bigger-grained than sand, I mistakenly assumed that the words “silica sand” must have been a mistranslation, and that they must have meant “silica gel.”

Ironically, it turns out that Mimi Litter’s “silica sand” looks like little BBs, while actual silica gel looks exactly like sand.

Since Mimi Litter isn’t a desiccant, I went to my local Michael’s craft store today and bought some Activa Flower Drying Art Silica Gel. On the Activa Web site, it says that a 1.5-pound bag of it costs $13.30, and a 5-pound bag of it costs $31.20 — but at Michael’s, a 1-pound bag of it costs $9.99 and a 5-pound bag costs only $14.99. I bought the 5-pound bag, and a sockful of it is sitting inside my closed guitar case right now.

© 2013 – 2016, ComputerBob. All Rights Reserved.

It is illegal to publish this copyrighted post anywhere else.

Tags: , , , , , ,

2 Responses to Too Humid Is As Bad As Too Dry

  1. Dear Computer/Reverend Bob:

    I came across your post about too much humidity and its adverse effects on guitar tops because I just experienced a similar issue with one of my guitars and have been poking around on the Internet. It’s not a good idea to leave the sound hole humidifiers in once spring arrives and the steam heat is turned off! Regarding your experiences with silica gel, I’d like to share with you a solution that I have found to work quite well. Not certain whether this is germane to you currently, but it is offered in good faith.

    During the winter, I keep an in-case humidifier in each guitar case. It is made from a travel soap dish with a hinged, snap-on lid in which I have drilled a 1.5-2″ hole with a keyhole bit. The soap dish is then touch-fastened or glued to the bottom of the case, just under where the peg head of the guitar rests, about an inch from the accessory pocket of the case. In the winter, I keep a piece of O-Celo sponge, dampened but not soaking, in the soap dish to keep the RH inside the case within the guitar’s tolerances. Works great.

    However, during humid New York City summers, I swap out the sponge for a Dri-Box: , which absorbs mositure inside the case and is completely reusable. The blue silica-gel beads turn pink when they are saturated. You just warm the box in a microwave oven for 15-20 seconds, and the pink beads should turn blue again when they have been voided of moisture. These little boxes work very well, and are much tidier than cat litter in a sock! I think they are pretty cost-effective, too.

    I hope your retirement and resurrected ministry are all going well.

  2. ComputerBob says:

    Dear Howard,
    Thanks for that information. I’m sure that some of my readers will find it to be very valuable! And thank you for your well-wishes — yes, my ministry is going extremely well. I’m very busy and there’s absolutely nothing I’d rather be doing!


Leave a Reply