Humidifiers

[lisadiane55]

Hi all - I'm a newbie to the site and relative newbie to mandolin. I went to buy a humidifier, expecting the type in my fiddle case, a plastic vial with screw on lid. But, it's a whole new humidifier world out there (humidifiers that fit inside instruments???). Any recommendations for my pristine new Eastman 305? I hope that the question isn't too insignificant. Thanks.

[John Flynn]

There are some fancy humidifiers out there and a lot of different opinions about them. I have done a lot of experimentation and reading on it. My personal approach is as follows: If your case is going to be closed with humidifier inside for more than 8-hour stretches of time, there is probably no difference in where the humidifier is in the case. Humidity tends to permeate whatever closed space it's in. Also, the "in the instrument" humidifiers have two hazards: First, they tend to not hold as much water as the "in the case" kind, and second, there is the possibility they can drip water inside the instrument, where the wood is not protected by a finish. That is not good for the wood.

After trying some expensive humidifiers, I actually have better luck making my own. Versions include: A soap case, like you would take camping to carry a bar of soap in. Drill lots of holes in it, put a piece of sponge cut to fit inside it and keep the sponge damp, not wet. Put it in the case. Other versions include a ziploc bag with holes punched in it and a sponge inside (make sure it doesn't touch the finish) and for small spaces, a plastic film can (you can still get them at camera stores), with holes punched it and a piece of sponge inside.

A great thing to have is a case hygrometer to see how well you are maintaining humidity. You should calibrate it with the "salt test" which you can find instructions for online. Also, accept that you probably won't get the humidity thing perfect and you don't need to. Well-made instruments are pretty resilient. The idea is to do the best you can at keeping your instrument at between 45% and 55% RH. If you get outside that to some degree, occasionally, you will still be fine.

[shortymack]

+1 on the zip lock baggie with a cellulose sponge in it. Simple, inexpensive and efficient. No need for the fancy humidifiers IMO. Just place it anywhere in the case, as long as you keep it moist it works great.

[George R. Lane]

Just remember to use distilled water, not from your tap.

[Andy B]

Following up on John's suggestion, I've been using a Planet Waves humidifier which is a small yellow sponge in a perforated plastic holder. It's meant to hang in the sound hole of a guitar but it fits in my mando cases next to or under the body of the instrument (which is where you want the humidity to go though as John said, the humidity pretty much equalizes throughout the case after a while). I had been using the Oasis guitar humidifier, but then during the winter I had one that didn't work. The sponge always works, and even during the winter I can usually go a week between having to soak the sponge. I use distilled water too. I had tried a violin Dampit long ago, but gave up on them because of the danger of leaks and because they were so small I had to refill them constantly. The Planet Waves unit always works, lasts a week between wettings, and doesn't risk damage to the instrument.

[almeriastrings]

The data does not agree with the hypothesis that placing a humidifier pretty much anywhere in the case is effective. In fact, what happens is that the area local to the humidifier experiences an increase in RH, but zones further away experience a very minimal effect. This is primarily due to lack of circulating air movement within the case. The case material also has a major effect, with wooden and fibreboard cases performing far, far worse than fiberglass or ABS cases (due to localized absorption and evaporation effects). Here's some real data:

http://www.mandolincafe.com/forum/sh...umidifier-test

This also includes evidence of just how poorly those typical 'case hygrometers' perform. They are next-to-useless. So, if you are relying on those to indicate how well your humidifier is working, you are pretty much wasting your time. Low cost electronic models are much better, but for real accuracy, you will not find it in a cheap instrument.

I also tested (not shown above) the effects of placing a humidifier around the headstock area, and in the accessory compartment. Conclusion: Hardly worth the effort. Minimal effect on the instrument body.

[shortymack]

So youre basically saying that placing a sponge anywhere in the case is just as effective as not having one at all? Im sorry, I just dont believe that no matter what the data suggests.

[almeriastrings]

Duplicate post.

[almeriastrings]

What I am saying is that the effect is extremely limited. In most cases, the localized zone of humidity created becomes trapped in 'pockets', and has minimal effect on the body of the instrument. This is easy to prove. Simply place a humidifier in a particular position, then take an accurate, laboratory standard and properly calibrated humidity data-logger and position that inside the instrument.

No-one is asking you to believe anything. This is easily repeatable. Try it for yourself.

In fact, if you tell me where exactly you would like me to position a sponge, what size, and what kind of casing it should be in, I will gladly run another test for you so you can compare to previous results. I can record three sets of data simultaneously:

1) Close to the sponge
2) Inside a mandolin
3) External (ambient) RH

[almeriastrings]

In most cases (excuse the obvious pun) there are only three viable positions for a humidifier:

a) Under the headstock
b) In the accessory compartment
c) Inside the instrument

Of those three, the accessory compartment is by far the worst in terms of allowing any humidity created to disperse evenly throughout the case. The headstock area is not good either, though precisely how poor it is very much depends on the physical properties of the case. Cases with a wide aperture between that area and the instrument body will typically do better than those with a more restricted aperture.

[John Flynn]

Just remember to use distilled water, not from your tap.

I have tried distilled water v. tap water extensively. The only place I see a difference is in electrostatic-type room humidifiers. I only use distilled in electrostatics due to the "white dust" problem. In all other applications, I use tap water and it works fine. Although I rarely encounter mold with humidifiers, when I have seen it happen, it happens with distilled water as easily as tap.

[allenhopkins]

I have heard that with Dampit and other humidifiers that use a saturated fabric inside a perforated tube or case, the minerals found in "tap" water will be retained when the water evaporates, and after a large number of saturations and evaporations, the retained minerals will decrease the fabric's absorbency and effectiveness. This is hearsay and I have no data to verify it.

My prejudice is to properly humidify/dehumidify the entire room where my instruments are stored. However, if the instrument is being kept in an area where acceptable humidity cannot be sustained, or if it's being moved frequently, a case humidifier is the alternative.

In my former apartment, where winter dryness was a major issue, I used some of the plastic bags that instrument cases are shipped in, which I scrounged from a friendly dealer. I put the humidifier (a Dampit) inside the instrument, then put the instrument in the plastic bag, then into the case. This created a "vapor barrier" around the instrument and, I hoped, led to slower evaporation and no absorption of moisture by the case itself. I had no problem with damage caused by dryness, but that could have been happenstance -- or the result of my clever expedient -- I dunno.

Now that I'm up around six dozen instruments, it would be impossible for me to monitor and maintain in-case humidifiers for all of them, so I rely on my basement crypt and summer dehumidification to keep them in decent condition. It's worked so far.

[almeriastrings]

I have heard that with Dampit and other humidifiers that use a saturated fabric inside a perforated tube or case, the minerals found in "tap" water will be retained when the water evaporates, and after a large number of saturations and evaporations, the retained minerals will decrease the fabric's absorbency and effectiveness. This is hearsay and I have no data to verify it.

That is absolutely correct. If you are in a very "hard" water area you will notice a difference very quickly. In a "soft" water area, it is not so important. One rough and ready way to know is that if your shower heads constantly block up you are indeed in an area you should be using distilled water for your humidifiers!

Keeping them in room with either humidifier or dehumidifier is an excellent method for those of us with numerous instruments. The smaller individual humidifiers are still useful, however, when taking them out for use or travel. In fact, even more important, because if you suddenly "crash" an instrument from around 50% RH to less than 25%, then cracks and other structural failures are even more likely.

[shortymack]

I live in the desert where humidity levels often reach into the single digits throughout the year. I have used the sponge in a bag placed either in the headstock area or under the neck joint (in my guitar cases, have only had my mandolin for not quite a month now and it has a levy gig bag) and have had zero problems with them. I used to place it into the soundholes but had leakage occur and stopped doing that. Thats what I base my claims on and is why I say I dont believe that the inefficiency is as bad as your data may suggest. Nothing less and it isnt a dig on your findings just a observation on mine.

Speaking of gig bags, I wonder how much they actually protect an instrument in relation to a HSC as far as humidity is concrned.


Allen, did you say 6 dozen instruments? WOWSER!

[Mandobart]

Just anecdotal evidence, FWIW. YMMV. I've lived in the arid western US most all my life. I never used any kind of humidifier on my old student Roth violin while growing up in NM. Never had any cracks or finish problems. Still have it and play it. Our home was not air conditioned either, so the RH in the house was the same as outdoors. Over the years I've accumulated several more instruments, and currently live in the shrub-steppe region of central Washington, where RH is always quite low and temperature swings from near 120 F in the summer to -20 F in the winter. I now use dampits or other sponge-type models in my instruments when in the case, and agree that they tend to dry out quickly. Most of the time my instruments are out on stands (I find I don't play as much if I have to drag a case out of a closet or out from under a bed). Once this summer when we had a stretch of 100 F+ for a couple weeks I had the AC cranked up. Any air conditioner (except evaporative, like a swamp cooler) will dry out the air in the space quite a bit. So during that time I used a cool mist humidifier in the instrument room. I've got 1 upright piano, 2 violas, 2 violins, 2 OMs, 2 mandolins, 2 guitars, a mandola and mandocello in the room. These range in age from 150 years to one year old. In the winter this room is heated with a wood burning fireplace insert. The only possible humidity related damage on any instrument is on my 40 year old Applause 6-string. I used to take it underway on the sub when I was in the USN. There are deep cracks in the thick finish of the soundboard that don't go all the way thru the wood. For the first 20 - 30 years of its life this guitar had no humidity control at all.

I'm pretty well convinced that normal diurnal/seasonal variations of temperature and humidity don't pose a threat to an instrument. Rapid changes in either of these should be carefully avoided.

[almeriastrings]

The answer to both posts above is two-fold. First, it depends on the instrument. Some are far more sensitive and susceptible to such changes than others. Many things affect that. Everything from the type of binding, end-grain exposure, finish properties, species of wood employed, grain directions, etc. There are a lot of variables. Plywood instruments tend to be least affected, but you can even see differences in response between two "identical" solid wood examples for the above reasons.

The other big factor is the time-scale taken for the "swing" in RH to occur. Sudden changes are much more likely to result in damage than slow changes. This varies hugely, according (again) to numerous variables. Everything from geographic location to what kind of house you live in. Larivee Guitars did a basic, but useful article on the consequences a few years ago:

http://www.musiciansworkshop.com/humidity.html

There is another useful article on the topic by Scott Zimmerman:

http://www.desertrosebanjo.com/wintercare.html

In short, depending on the variables, you may "get away with it", on the other hand, you may not.

[lisadiane55]

Thanks to everyone who posted. Lots of helpful info. I'm in western Massachusetts. I was told that I don't need a humidifier in summer, just during the drier months. I've kept my vial-type humidifier, filled with tap water, in the accessories compartment of my fiddle case for over 10 years with no visible problems. Is that type of humidifier not made or recommended anymore?

[TheMandoKit]

Interesting that with all that has been written about keeping instruments in properly humidified surroundings, opinions are so different.

I live in an old house with radiators/hot water heat, and in the winter time, the RH can get down to desert conditions. I like the idea of humidifying the room, rather than the case, and run a Venta humidifier in the room where I keep instruments. Generally, I can keep the RH up to around 40%, but when it gets really cold, it is a challenge to keep the RH up without having water run down the walls. That's when I add the case humidifiers. I have tried just about every kind out there, and I really like the Oasis model. They do not leak, you know when it is time to add water, and are easy to fill. I use the "in the instrument" model for flat-top guitars, and the in-case model for mandolins. Archtop guitars are a challenge, so I still use the old dampit type, plus a second case humidifier by the accessory pocket.

I will echo comments above about distilled versus tap water if local water is hard. I live in the upper midwest, and the water here is high in mineral and iron content. I have had Dampit-type humidifiers go south in one season. The minerals will also kill the water holding crystals in Oasis humidifiers quickly. I only use distilled water.

As always, YMMV.

[Paul Merlo]

The super-dry season is waning, but I thought this might be a helpful discussion for someone.

I bought an Oasis Ukulele model humidifier and can manipulate the strings to fit it into the oval soundhole of my mandolin. I need to use two hands, and have dropped it inside a couple times too. I have to bend the strings a little bit, and it's rather a pain to get the suspension bar to suspend from the strings. I'm very careful during the process, but there are risks of damaging the soundhole binding or worse if I slip. But I think it's a better situation than nothing. I can tell it's working because the maple and spruce aroma is prevalent when I take a whiff.

I store it flat (mfgr recommend for uke), but the bottom end of the humidifier (which is non-permeable rubber and intended to?) rests on the inside of the back. It's just the rounded corner of it, so I imagine the contact point is about as big as Washington's forehead on a quarter. I looked inside, but couldn't see any evidence of damage at all. I thought I saw some, but realized it was the unfinished flames on the inside of the back.

Does anyone use something similar? does this make you uncomfortable? any other thoughts?

[courses]

I have heated with wood stoves everywhere I lived for over thirty years. There is a water bucket on the stove, but the house is pretty dry. None of the many instruments I have owned ever showed any sign of a humidity related failure or trauma, including some vintage pieces and new ones. Guitars mandolins and horns live under the beds, in their cases, and an old plywood bass stands in the corner.

Average temps & humidity in the summer months aren't extreme. Have I just been lucky?

[Tommando]

More anecdotal evidence. I live in an area where humidity is relatively high most of the year, but gets into the 15-20% range for a while in the winter. Gas and electric heat make it pretty dry in the house. For about 40 years I left my guitars sitting out. No humidifiers. No problems. I bought a nice Martin guitar a few years ago and the dealer told me to use an in-case humidifier in the winter. Then I bought a mid range Martin guitar. Subsequently, four of that same model were brought to me needing repair. The top center seam had begun to separate on all of them. Diagnosis: thin top dried out - never been humidified. Now, all of mine stay in the case, with humidifiers as long as the heat is running. The humidifiers are mostly in the pick compartment. The best I’ve found is the perforated zip lock bag with a damp (well squeezed out) cellulose sponge inside. The sponge gets hard when dry, so it is easy to know when to wet it. For instruments without cases, I put the bag in the sound hole and tape it on with painters tape. The only problem is if the sponge is too large for the hole, you can't get it out when dry. My top-end Martins have a finish on the neck that gets a little sticky when damp. The necks get sticky with the humidifiers in the pick compartments, and my inexpensive gauges show good humidity in the entire case. I have several different kinds of cases for the guitars and mandolins. and it works the same for all of them. YMMV.

[justinhart]

I just purchased my first mandolin and did quite a bit of reading on this subject, as it is still winter here. I opted for a in case Oasis humidifier that stays in the bottom of the headstock section of the case. I don't have a hygrometer to test the levels but it is dispensing liquid so it must be working. Not sure if this is the best solution but the only one I have right the moment.

[Bill Clements]

Here's an idea:
http://www.amazon.com/Stretto-Humidi...ent+humidifier

[J Mangio]

Ditto to courses.

[eastman_315]

Just my personal humidifying experience:

For my guitars, I have cut strips of that super-absorbent cloth that they sell at boat/rv/garden/etc. shows, dampened them, rolled them up & put them in multi-holed film cans in my guitar cases for years. I attached buttons to some of the film can tops & suspend them inside guitar sound-holes, with non-buttoned ones in the cases near where the neck joins the body. I have a bunch of those cheap cigar case hygrometers that I swap out among the cases, & while not super accurate, I can usually tell if a case (or instrument) is getting too dry. I try to keep readings between 40-60%. I only use these when the heat gets turned on for the winter. No AC in my house for the summer. :-(

I have space near the neck/body joint in my mando case & will put one of my film can humidifiers there. Unfortunately, since the mando is so new to me I leave it mostly on the stand so I can grab-n-play whenever I have the time. My Chinese-made Voyage-Air VAOM-02 guitar is laminated so it always sits out on a stand to play while my Martins live in their cases whenever they're not being played during the winter months.

My approach might not be perfect but so far its worked well for me. Better, IMO, than doing nothing, for sure.

That's my story & I'm stickin' to it!

Frank