Dry Guitars - Moisture Content Meters & Case Humidifiers

[Steve Baker]

Anyone in the repair world use a digital moisture content meter to gauge the dryness of a guitar? Obviously guitars show you when they're dry with fret ends, collapsed tops, cracks, etc. but we're considering using a meter if for no other reason than to have something quantifiable to show customers. ('It came in at X%, it's going home at Y%') Any recommendations?

 

And what case humidifiers do you like? Humidipak doesn't last long enough; Oasis works great as long as you fill it every week. We've pretty much narrowed our recommendations to those two but would love to hear about any others. (We're done with Dampits, sponge humidifiers,etc.)

 

Thanks everyone!

[Jeff Highland]

As far as I know.

 

-Wood moisture meters require you to stick two pins into the timber

-They do not work accurately on thin timber

 

Both these to me mean that this would not be a good idea..

 

[Steve Baker]

A fair thought. I do know that we used one many years ago in guitar building school - albeit on uncut top woods. It was the measuring stick for when we were done kiln-drying a top and it performed fine. As far as its usefulness in a repair, the thought would be to use it through the sound-hole on the inside of the guitar - maybe a head block or brace, obviously not on a finished surface. You'd definitely need to be careful not to drive the probes deep enough to cause problems.

[Paul Hostetter]

I don't like any humidifiers, other than whole-house (or at least whole room with great consistency) humidification systems. The in-soundhole or in-case items are for very temporary situations. I seriously doubt there's any product—a meter to have something quantifiable to show customers—that would help your needs at all.

[Gary Fried]

There is no need to quantify dryness to a customer.  I live in NYC and this winter destroyed guitars.  People came in with strings touching the frets with full height saddles and cracks from the bridge to the end block that were wide enough to drop a quarter through.  When they left their guitars played great and the cracks were barely visible. I make up about fifty sponges sealed in ziplock bags and stuff five into each dry guitar as well as keeping my shop humidified with a room humidifier connected to an ice maker line.

[Charlie Hoffman]

Here in Minneapolis we have confronted this problem for 40 years. Every year in the heating season we will see 400 - 500 guitars which are severely dried out and probably 200 with top cracks.    I agree that a moisture meter won't show much but there are moisture meters which do not require pins penetrating the wood.  I don't have one so I don't know much about them.  As to how to humidify guitars, I am going to have to disagree with Paul.  Around here (I don't know about Calif) they are the only thing that can work. Keep the guitar in the case with at least one humidifier.  We like the Kyser soundhole humidifier the best.  The old fashioned "soapdish humidifier" works well but around here any humidifier needs to be refilled at least twice a week.  It is not enough to keep the room humidified for several reasons:  First room humidifiers are as unreliable (needing frequent refill) as any other and, second,  around here at about 25 - 30% humidity the moisture condenses on the windows and the room won't get any better.  The real problem is that guitar owners simply don't do it even when they have been clearly told how to care for the guitar.  We hand out a free brochure to all of our customers and they still don't do what they need to do.  Ah well!!!

[Paul Hostetter]

Charlie, my experience with humidity issues is from my considerable time in Denver and Detroit—we have relatively nothing to discuss in California, but my clients are from all over the place, and I've lived and worked in places with fierce dryness in winter. Heck, Denver is dry all year round.

Case humidification is spot humidification. The instrument goes through a rollercoaster of situations every time it's taken out to be played. Surely you don't keep all the instruments in your shop in their humidified cases. Room humidifiers only fail if the humans attending them fail, and it seems Gary Fried has solved even that, by having the humidifier attached to an ice machine supply. I really believe that the window condensation is a clear indication that you are getting results with your room humidification.

 

Spot humidification is certainly better than none, but doesn't begin to compare with humidifying the entire environment. It's better for general human health as well.

[Gary Fried]

Paul you are right. If you walk past my shop during the winter my windows are fogged up to the point that they are causing some corrosion on my steel doors. If you are wearing glasses they will fog up as soon as you step foot in my shop.

[Steve Baker]

Thanks for all the responses everyone. It appears we've employed a hybrid of everything that was mentioned here over the years. Currently we have a furnace unit that keeps the shop around 55-60% and use toothbrush tube humidifiers with especially dried out instruments. We sell Oasis and Humidipak but know they are only as effective as the person who maintains them. That recipe seems to be 99 point something effective in our 12+ years. We mostly are looking for the right system to sell our customers to best maintain the work we've done. Whatever the ideal way to do it, I think all we can do is sell the case humidifiers with warnings that that Chicago is just a tough place to keep a nice guitar healthy. Plan on coming back to see us in a few months.

 I think Charlie has settled into the same perspective we have - give them all the information you can, and hope some of them do it - even if you know most of them won't. I think we'll start putting the written notice in with repaired acoustics too.

We joke that we're like dentists that can tell who really flossed and who didn't. A top that cracks again = someone who didn't learn after that first root canal!