Controlling humidity on a budget

[Alan]

Greetings from the Nation's Capital,
As a would be guitar/uke builder, I am seeking advice on how to control humidity on a budget. I have my small stash of tonewood in my study inside our house. Even though fellow Canberraan instrument builders have indicated that our climate doesn't present significant humidity problems, my digital hygrometer indicates the humidity in the study changes much more than I would like. Last week when we had a 37 degree day and the air conditioner in the house running, I closed the door of the study to reduce the influence of the air-con but the RH still went down into the 30% range. Yesterday when we had drizzly rain and later a storm it rose, to the 60% range. Today it is a fine sunny day and the room is at 36% RH. Last summer when all of the east coast of Australia was in an extended heat wave, the RH went down to the 20% range in this room
How can I keep the humidity in the 40% to 50% region?
My brick garage where I do my woodworking activities can be even worse with the RH high in rainy times and extremely low in the summer, especially in the afternoon when the west facing steel roller doors transfer heat into the garage.
Ideally i would like to store my tonewoods and do my glue ups in the garage and could build a smallish room inside the garage for tonewood storage and glue ups but I would need to be able to control the humidity with a degree of accuracy to warrant the cost of bundling the small room in the back corner of the garage.
Any advice would be appreciated.

[Bob Connor]

G'day Alan

You don't need to store your tonewood in 45% RH, in fact it's probably good for it to "enjoy" the seasons that Canberra will throw at it. Many a renowned Spanish luthier stored their tonewood in the roof space of their houses.

The wood only needs to be at 40-50% RH for a week or two before you build with it and the crucial time is when you are jointing plates and glueing braces.

Build a box that's big enough to store a guitar top or two and put a light globe and something to measure the humidity in it. If you can find someone who still has some incandescent globes grab them.

I don't worry too much about the sides. You're going to cook them and slash water all over them when you are bending any way.

Regards

[Alan]

Many thanks Bob, that's a very helpful reply - perhaps I am a little paranoid about humidity.
The box with a light sounds a good way to go for tops, backs and braces. I assume the incandescent light will dry excess humidity but if the humidity is low do you place a wet sponge or similar in the box?

[bdunne]

Hi Alan,
I have also had similar concerns since moving part of my building activities to my partners garage. When the sun hits the roller doors in the afternoon the RH plummets! I have taken to keep my builds, in various stages of completion, in large space bags I got from Costco. I only bring them out when the RH in the garage "is in the ball park". Seems to be working ok so far. I'm still trying to convince her I should store them in the house somewhere, but I would probably still keep them bagged.

Brian.

[lauburu]

I've seen an old fridge, with an incandescent bulb installed, used to store tonewoods imediately prior to and during builds. According to the owner it worked well.
Miguel

[Craig Bumgarner]

For what it's worth, I use a cheap dehumidifier in the summer and a misting humidfier in the winter. I have a gauge in the shop and control the humidity devices manually. I probably have $150 US invested in the humidifier, dehumidifier and gauge. My shop is ~ 300 sq. ft, heated by base board electric and cooled by a window air conditioner. (window air conditioners don't scrub much moisture out of the air compared to central air units which recirculate the air). The climate here in the mid-Atlantic region of the US is temperate, four seasons. In the summer the humidity in the shop can be quite high, in the winter bone dry. Without too much effort though, I can maintain my target RH, 40%, year round.