Humidification

West R Lee

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Just a reminder. Here in East Texas our humidity for about 10 months of the year remains relatively stable at around 50%. Sometimes it fluctuates between 42% to 52%. This time of the year, on cold days we turn our central heat on and yesterday the humidity in that room dropped to 24%.

I keep two hygrometers in my music room and both stay within about 2% of each other, and one of those hygrometers is very small about 2" square, and small enough to stick inside a case. Yesterday I conducted a small experiment to determine just how much difference a sound hole humidifier makes to say a small glass of water in the case, along with the sound hole humidifier. This is something I've done in period of dryness here, but I'd never checked how much difference the container of water really makes.

With the sound hole humidifier, and with 24% humidity in the room, I was able to achieve 37% case humidity. Grant you the majority of moisture is contained within the body of the guitar with the sound hole humidifier. With the small glass of water in the case, along with sound hole humidifier, I was able to get 47% in the case, with 50% being ideal according to most manufactures. Some of you have room humidifiers and some may even have humidifiers as part of a central system, but for the benefit of those who do not, I thought the experiment worthwhile.

Most of us are aware of this, but a reminder from Collings:


Humidity and Temperature

Fine guitars are made of thin pieces of solid wood that are glued together. They are directly affected by humidity and temperature.

Humidity is the amount of water vapor or moisture in the air. Temperature affects the amount of moisture that air can hold. Both of these factors affect wood because it is naturally "hygroscopic". This means that it takes on and gives off water. Therein lies the challenge.

A guitar that absorbs too much moisture, through high humidity, expands and swells. This distorts the geometry of the guitar and, consequently, its tone and playability. Add high temperature, and humidity can weaken glue joints and even cause them to fail. With prolonged exposure, the glue under the bridge will weaken, allowing the bridge to pull off. Telltale signs of a "wet" guitar:
High action
Swollen top
Fret buzzing in the high registers (as fretboard rises with the top)
Distorted back and sides
"Tubby," muffled tone, low volume
Finish cracks
Bindings separated

Overly dry conditions, or lack of sufficient humidity, can be equally detrimental to your guitar, causing the wood to shrink and crack. It can also cause poor tone and improper intonation. In dry regions (mountainous or desert areas) or northern climates, where heated air is common in winter, simple guitar humidifiers may not be sufficient. Room or household humidifiers may be necessary to maintain a proper environment. Telltale signs of a "dry" guitar:
Lowered action
Fret buzzing and lifting
Fret ends sticking out from the fingerboard
Dips in the top or back
Finish and/or wood cracks

Gradual changes in humidity and temperature will generally not harm a well-made guitar. At Collings, we build and acclimate our guitars in an environment of 49% relative humidity and a temperature of 75 degrees. So if you keep guitar pretty close to these ranges, you should have no problems.

The biggest danger caused by humidity and temperature is rapid or extreme changes. That’s because different parts of the guitar shrink and expand at different rates. For example, if your local humidity drops very rapidly, the guitar cannot acclimate itself uniformly, causing cracks or failure of glue joints in different portions of the guitar as it tries to "cope" with the drying situation. The same is true, in reverse, with high humidity.

Extreme temperatures can wreak havoc, too. Heat weakens glue. Cold "chills" lacquer causing finishes to crack or craze.

While you can’t control the weather, you can control your guitar’s environment to a great extent. Here are some simple pointers.
 Keep your guitar in its case when you’re not playing it. Collings guitar cases are virtually air tight – and it’s a lot easier to control humidity in a smaller volume of air.
Purchase a home hygrometer/thermometer to keep tabs on the relative humidity and temperature. Adjust your home environment as necessary. Plants and humidifiers add moisture in dry winter months. Air conditioning controls humidity in the hot, muggy summer months.
Avoid storing your guitar near sources of hot, dry air (such as forced hot air heating ducts), or cold, damp areas (garages, basements, closets with outside walls).
Never transport your guitar in a car trunk. Temperatures inside car trunks are extreme in any kind of weather. It’s the quickest way to destroy a guitar. Even in the passenger compartment your guitar can be subjected to extreme temperatures. For example, please allow your instrument to warm up slowly before opening your case in a warm room after being transported in a cold vehicle. Abrupt changes in temperature can cause (ie: cold guitar to warm room) can cause finish crazing.
When traveling cross country, keep in mind changes in local humidity – and protect your guitar accordingly.
Guitar humidifiers that fit inside the soundhole or extend into the body can be very effective but must be used with great care to avoid water damage. Check with a qualified guitar repair person before using them.

West
 
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Cougar

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....This time of the year, on cold days we turn our central heat on and yesterday the humidity in that room dropped to 24%.

It's about the same here in the Wild West (Salt Lake).

With the sound hole humidifier, and with 24% humidity in the room, I was able to achieve 37% case humidity.

How big is the sound hole humidifier? I'm thinking the more surface area, the better. I've got three half sponges in a baggie full of holes. I don't squeeze the water out of the sponges too vigorously. Keeps it into the 40s. I'm hoping that's good enough.

Grant you the majority of moisture is contained within the body of the guitar with the sound hole humidifier.

I think a big percentage of it is in the case lining. Keep the case closed when you're playing!
 

Rayk

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I run between 37 - 45 this time of year up to 50 ish in the summer never had an humidity related issue yet.
 

West R Lee

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I run between 37 - 45 this time of year up to 50 ish in the summer never had an humidity related issue yet.

Only on colds days when we have to run the heat all day here Ray, but it happens. Just looked at the music room and it's at 28% right now.

West
 

Rayk

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Only on colds days when we have to run the heat all day here Ray, but it happens. Just looked at the music room and it's at 28% right now.

West

Yeah that’s dry .
Just checked my meter on the fridge no specific room for guitars but 4 are in my bedroom I’m gunna move the meter in there I’m sure it’s lower .

Anyway I bought a Honeywell quietcare humidifier not sure they make them any more but it’s nice and works well .

Just checked
This must a newer model mine was like 90 bucks any I’d buy it again just might now I think about it lol

Works well only sucky part is the filling of the tanks the lids gets tight maybe this model has fixed that issue . I give it a 9 lol

https://www.honeywellstore.com/stor...cool-moisture-console-humidifier-9-gallon.htm
 
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F312

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Yeah that’s dry .
Just checked my meter on the fridge no specific room for guitars but 4 are in my bedroom I’m gunna move the meter in there I’m sure it’s lower .

Anyway I bought a Honeywell quietcare humidifier not sure they make them any more but it’s nice and works well .

Just checked
This must a newer model mine was like 90 bucks any I’d buy it again just might now I think about it lol

Works well only sucky part is the filling of the tanks the lids gets tight maybe this model has fixed that issue . I give it a 9 lol

https://www.honeywellstore.com/stor...cool-moisture-console-humidifier-9-gallon.htm

That's the one I use. Whole house 1900 Sq. ft. Stays at 45%- 55% on low. Start backing down when the furnace is not running as much, fully automatic. You don't have to tighten the lids , just a light snug. Even the closets get saturated.

Ralph
 

Bill Ashton

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Wes, really good info, and thanx for that. Here in New England, the rule of thumb has been "when you turn on your heat, start humidifying your guitars."

I lagged a bit behind on that, "global warming" believed or not, as the humidity stayed high. Have been using Oasis units for several weeks now, and seem to have to fill them about every ten days or less. Steam heat (modern, like ten years old) in this old house, even though the room where the guitars are has been gutted and insulated according to the latest building code standards (PIA, but won't go into that).

Yesterday I look at the two D'Addario electronic meters just free standing in the room, and though they are a point or two apart, both are in alarm :grief:

Gotta say, all the Oasis are all scrunched up, dutifully filled them all with distilled water. All guitars are stored in their hard cases. Moved the free standing humidifiers into the Collings and Guild cases.

Will report back how we are going...just for reference, my first "good" acoustic guitar was a 1995 Gibson J-30 which was never humidfied (to my complete ignorance), but over the 16 years of ownership never showed me a problem...steam heat?

Cold days in Tejas? Whats that, 75 degrees...though I understand some members have actually gotten snow? "What is this?!!!" Friend in Georgia has been snowed in. That storm I think has hit us today...maybe 2-3" on the ground, no big deal
 
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Rayk

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That's the one I use. Whole house 1900 Sq. ft. Stays at 45%- 55% on low. Start backing down when the furnace is not running as much, fully automatic. You don't have to tighten the lids , just a light snug. Even the closets get saturated.

Ralph

I have a mobile home not the best windows so it can’t bump it up that good unless the moister is up outside .

Yeah I learned to just snug the lids wish they could free stand lol
I also add a drops of bleach to each jug to keep any bacteria from forming .

I seen some bigger humidifiers but they make to much noise so this one is a win .
 

West R Lee

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26 here this morning Bill, but along with that comes really dry air in a normally humid outside environment. Then combine the indoor heat and it's can get pretty dry in here.

West


Wes, really good info, and thanx for that. Here in New England, the rule of thumb has been "when you turn on your heat, start humidifying your guitars."

I lagged a bit behind on that, "global warming" believed or not, as the humidity stayed high. Have been using Oasis units for several weeks now, and seem to have to fill them about every ten days or less. Steam heat (modern, like ten years old) in this old house, even though the room where the guitars are has been gutted and insulated according to the latest building code standards (PIA, but won't go into that).

Yesterday I look at the two D'Addario electronic meters just free standing in the room, and though they are a point or two apart, both are in alarm :grief:

Gotta say, all the Oasis are all scrunched up, dutifully filled them all with distilled water. All guitars are stored in their hard cases. Moved the free standing humidifiers into the Collings and Guild cases.

Will report back how we are going...just for reference, my first "good" acoustic guitar was a 1995 Gibson J-30 which was never humidfied (to my complete ignorance), but over the 16 years of ownership never showed me a problem...steam heat?

Cold days in Tejas? Whats that, 75 degrees...though I understand some members have actually gotten snow? "What is this?!!!" Friend in Georgia has been snowed in. That storm I think has hit us today...maybe 2-3" on the ground, no big deal
 

Bill Ashton

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Right now, like they have in NJ...28 degress, with 3 1/2 inches on the ground, coming down at a good clip. Probably see that 5 or 6" they claimed, but if its like it is now, just light and fluffy and not worth uncovering the SB.
 
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