The first sign of Spring coming was noticing my wooden jack plane now has a twisted sole. Ah yes, the weather is changing!
I keep the humidity in my shop relatively stable by using a humidifier during Winter and a dehumidifier in the Summer. A hygrometer helps me tweak everything to keep the environment between 45%-50% humidity.
Humidity control is very important in many woodworking shops but it is critical when making musical instruments. The thin wood used in stringed instruments can warp or split easily with changes of environment. Some slight movement in a fingerboard can cause an instrument to become difficult to play.
By building instruments in a environment of 45%-50% humidity the final instrument will be fairly stable in more humid environments and won’t react too quickly to somewhat lower levels of humidity.
Still, it is important to use a humidifier if you live somewhere with low humidity or if the air in your home is very dry. You can keep the instrument in a case with an instrument humidifier or keep a room for your instruments at the proper humidity.
Some early signs of an instrument drying out are:
- The ends of the frets feel sharp (the fingerboard has shrunk)
- The action suddenly feels different (the fingerboard has moved)
- Noticing buzzing on frets that wasn’t there a few days before (see above)
- Humps, warps and other distortions in the top, back etc.
If caught early returning the instrument to proper humidity will soon reverse the problems. If the instrument is not returned to a proper environment damage can very likely occur. You’ll notice major warping, cracks, etc.
Now I am off to true the sole of my favorite wooden jack plane, check the humidity of my shop and get back to work!