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I need to know how important it is to control the humidity in my shop when I am not actually bracing or gluing the top back and sides to close the body. I am running heat and a dehumidifier constantly now, and the cost is prohibitive. I just went online to my account at my local utility company, where I can view my daily use through a smart meter they installed. What I saw scared the out of me! I started running both the heater and dehumidifier a week ago when the weather turned and I started the bracing and assembly process. My daily electric use in that time has doubled! At this rate, I can no longer afford to build guitars. Is it ok to turn it off until I start bracing and assembling the next one, which will be in a few weeks (I am building 3 at once)? In the meantime I will be doing things like bending sides, binding, etc. The guitar that I assembled this past weekend is now in a case in the shop, but still needs binding, etc, and has no finish on it. I can bring the case into the house, or leave it in the shop. It will not get below 50 degrees in there, but the humidity may go up. Any thoughts? Thanks, Wendy

Wendy -

Do you have a view of what the actual humidity is in your shop? Of not, go get a couple of cheap hygrometers. I'm a bit confused when you say you are running the heater and dehumidifier at the same time. In my setup, I'd end up with a VERY dry shop. When the heater is on, I run a humidifier, not a dehumidifier.

Others with more experience will chime in - here's what I do. I shoot for humidity as close to 40 % as I can year round - in the summer it goes up to 50% - so be it. I run the air conditioner in August, as much to protect the wine that I also store there, but the added benefit is it keeps the humidity below 50%. Under 40 (in the winter, I get a bit nervous and run the humidifier. I don't think temperature is as much of an issue (within reason).

I'm sure some will tell you they work on other stuff when they are outside of reasonable parameters - and close up boxes, glue braces, etc. when the wood is at equilibrium in a room that is at about 40 - 50% humidity.

I usually maintain it at close to 45%. I am located in AZ, so I usually end up running a humidifier, not a dehumidifier. We recently had a cold storm front move through from the Pacific, so the weather changed drastically. It is cold, hence the heat, and we have had a lot of rain and the humidity went way up. My shop has an unsealed concrete floor. If I were planning on continuing to build after these 3 guitars, which I may, I will definitely move everything and seal the floor. The rain has cleared up today, and I probably could just run the heat on low for now, but there is another storm getting ready to move through. I have never built here in the winter before. I have always built in the summer when our monsoons come through and the humidity goes up. Then it is very easy to control with the A/C and a humidifier. I do have a good hygrometer which I check periodically. I will definitely control it during the crucial parts of the build. I really just need to know whether the assembled guitar needs to be controlled until the finish goes on it, and if everyone controls their shop environments at all times or just during assembly and bracing.

Wendy,
I think you'll find a lot of people in the same situation. From what I've gathered from other threads, you're OK doing things like binding and sidebending in less than ideal conditions. Jobs where you want to have the wood just right, like bracing the top and back, assembling the body, and angling/fitting your neck, you'll want to make sure the wood has stabilized for a few days between 40-50% RH before attempting these tasks.
I've read about some makers who will stack up work until the humidity is more reasonable. So they would make a bunch of frames, cut braces stock, rough out neck blanks, slot FB's etc., anything where RH is less critical, and then when the humidity is right they'll just go to town on the jobs where it is more critical to have correct RH.
And for what it's worth, having the wood dry out is worse than having it be too humid...
Hope that helps a bit, let's see what others have to say!

I have my basement shop set up in three rooms. I keep one of the rooms heated and humidified to 40 - 45 %. I use a dehumidifier in the summer and a humidifier in the winter. I will probably add an air conditioner next summer as well. I use this room for all assembly and gluing. The other rooms are for sawing and sanding and for spraying and storage. If you can't set up a small room, then perhaps a climate controlled closet or cupboard to keep the work in when you are not working on it. There is usually and economical solution.

Ron