Humidity Discussion

What happens to a guitar when it's dried out?

Here's one example.

The critical geometry is completely affected. Setting up the guitar is difficult. In addition to this, the entire structure of the instrument is under abnormal tension. There are many different pieces of wood glued together inside a guitar, different types of wood, with grain lines pointing in all different directions; when these various components of the instrument dry out, they contract in different directions and to varying degrees of subtlety. This creates undo tension throughout the structure of the instrument and it therefore doesn't play the same, and it doesn't sound the same either.

It's true that not all guitars or like instruments need the be humidified to prevent cracks or "visible" damage. However, when someone brings me a guitar that is dried out, even if they are happy enough with it's playability, the damage is visible to me.

I've also seen many older instrument that have been dry for a long time. Some say the guitar has been "acclimated." Rarely is a guitar properly "acclimated," and some guitars refuse to "acclimate." Some of the older instruments don't show much extreme trauma, but none are in pristine condition. Most have had crack repairs and other work done to remedy the effects of being turned into guitar-jerky.

Keep in mind, a guitar with the correct geometry, kept at the right humidity, plays and sounds the best. Too much humidity makes the guitar play and sound horrible as well. However, too little humidity is generally more detrimental to the structural integrity of the instrument. And besides, you will never have a problem with excessive humidity if you live in northern Arizona. So get a humidifier already!

My next post will discuss how to properly humidify your instrument.

Humidity Warning

I've removed the blog-hydrometer for now because the humidity in your home is nowhere near the humidity outside. Your indoor humidity is much, much lower than outside. Any and all heaters (some more than others) dry out the air in your house. At the store we've had to get out extra humidifiers to keep the humidity in the acoustic room at a high enough level.

So, check those humidifiers. Think about supplementing your case humidifier with a room humidifier. Remember, we live in one of the most arid climates in the US. The effects of this environment on wooden instruments should not be underestimated.

Next week I'll write more about the specifics of what happens to instruments and the adverse effects of extremely low humidity levels like we have here in norther Arizona. If you need more info about keeping your instrument properly humidified, contact me at the store or by email.

Glue that Back back On

You may be wondering, why so many clamps?

I had to remove the back (which was already lifting in various places around the seam) on this Kamaka ukulele to replace a back-brace and reglue another brace on the underside of the top. This is a small soprano uke, so the only way to get inside was to remove the back. The problem was originally caused by dryness. Coming from Hawaii, the instrument did not take well to the dry climate of northern Arizona. Because the instrument had been dried out, braces were lifting and the body was slightly warped.

So, this is why I needed so many clamps to properly glue the back in place. Four of the clamps are being used to simply hold the sides in the correct shape to accept the back into proper position. Because the wood had dried and warped, after the back was removed the sides didn't stay in the same shape... i.e. they were being held in place by the back prior to its removal.

As to why so many different types of clamps were used... I didn't have enough spool clamps for the entire job... also, spool clamps would've gotten in the way of the the clamps that were used to keep the sides in the correct position.

This was a beautiful, authentic Hawaiian uke with some great pieces of koa wood. It was a pleasure to bring this instrument back to life. After the structural work, I did some minor fret work and made a new bone saddle.

-- Ryan Elewaut

Mando Acclimation

Here is a repair I did about a year ago. I replaced the bridge foot on this Stiver mandolin with one I fabricated from an ebony blank. The need for this repair was due to a typical northern Arizona instrument problem. The mandolin had dried out and "acclimated" to our dry environment, which altered the geometry of the instrument. The neck angle was so high that the original bridge could not be raised tall enough to yield appropriate playing action... strings were too low to the fingerboard and it was buzzing like crazy. While I was at it, I leveled frets and setup the mandolin as perfectly as possibly with a new bone nut.








After making the new bridge foot, it was important to sand the bottom of it to precisely match the contour of the mandolin top.








This enables the best transfer of sound vibration from the strings, through the bridge, and into the body of the instrument. Anything other than an absolute perfect fit is unacceptable in this case.









Here you can see the old bridge foot,














the new one made from scratch,














and both side-by-side.



The new bridge foot is almost 1/4" taller than the old one. I made it just tall enough for the strings to setup at the proper height once the bridge saddle was put into place on the posts. I didn't want to make the new piece any larger than necessary. By making it as close to the original size as possible the original sound of the instrument would be preserved as much as possible.




I didn't take any final pictures of the completed project. But this repair was a complete success and the customer was extremely pleased with the renewed playability of the instrument.

(Post Script) It should be noted that trying to purposely acclimate a fine instrument (such as this one) to the dry humidity of Flagstaff is usually unrecommended, if not highly discouraged. It is much easier on the instrument, and on you as the owner to simply invest in and learn how to use the appropriate humidifier, and more importantly get in the habit of keeping the instrument properly hydrated. The owner of this instrument was lucky we didn't have cracks to fix or any major structural repair, worse than what we saw, anyway.

-R.E.