johnd wrote: ↑
Wed Jan 31, 2018 7:40 pm
BellyDoc wrote: ↑
Wed Jan 31, 2018 7:30 pm
I made it into a cool DIY project and converted trash into treasure. An old armoire for a large screen tube TV became a glass paneled humidity control cabinet. It holds 6 guitars but has room for 8. Humidity is kept rock stable at 43%
How do you control the humidity?
I did a good job sealing, first of all. All the cracks and crevices were filled with West System epoxy before liberal finish coat applications, and I created a door seal system that works well enough that it hisses when I open and close. Second, I used a saturated salt solution for humidity stabilization.
It's an interesting point of physical chemistry that, in a closed system, different saturated salt solutions will equilibrate at different stable relative humidity levels. I use Potassium Carbonate, KCO3, which is a food-grade product. I bought a kilogram online, mixed up a saturated solution with most of it and then tossed in the rest as solids for the bottom. Then I poured the solution into a gallon bucket and put a cylindrical evaporative filter from a humidifier in there just to help increase the effective surface area for exchange.
Room humidity in my office/music hideout is currently 34% and the instrument cabinet is at 44%. If I were to leave the cabinet door open for a while and then close it again, it would drop toward ambient humidity in minutes and then climb back to equilibrium in an hour or two. Most of the time when I open the door long enough to take out or return a guitar, I'm unable to see a change on any of the hygrometers (there are 3) in the cabinet.
I'd post pictures, but I haven't had a picture hosting site since photobucket ended free hosting.
"If I have seen further it is by standing on the shoulders of giants." -Sir Isaac Newton
Armin Hanika 56PF