How to control temp and humidity

[Woody OKeefe]

I built my first two guitars in the California Desert, and still in the summer it was 65% rel in the summer and 20% in the winter inside my house. Now I live in Prescott AZ 5200' elev. and 16% rel hum. My realization is to build dry. Like everyone says it depends on where you live and where your guitars are going to be used.>

[Coach]

Personally I would not hesitate to assemble a guitar at 27% RH ...........

Now a guitar that is constructed in dry conditions will obviously be likely to react to very high humidity (stormy day) -- the action will change, generally higher since the top will dome a bit more. But -- cracks and failed glue joints probably will not be an issue.

Ok then. How about the summer months when the RH is around the 40 to 55 % level? Will I be fine assembling at around 30% (other than the higher action)?

I'm learing here. So is it common to reset the action according to season?

[Kevin Sjostrand]

Woody,
We have some friends in Prescott. Never been there, but I hear it is a great place, and they love it there.

Kevin

[kencierp]

Dealing with humidity change is on going -- Guitars like Rainsong with its carbon fiber construction are the exception. Some makers include a pair of saddles one for summer and one for winter. Again, raising the humidity in a room is pretty easy -- just add water. Protecting an instrument is simply vigilant use of a case humidifier.

Start building --- stop worrying -- its far more fun. $.02

[Coach]

We have a central air with built in furnace and AC ventilation system in our home. I've tried, a couple buckets of water seem to have little or no bearing at raising RH.

Thanks guys. I'll go right ahead and start building. Another question I do have though: how high RH can you build at and not have a problem later when the RH falls down to 25% for prolonged periods? Is 35% too high.

[Darryl Young]

Over 45%, be leary......at least for gluing cross grain braces.

[David L]

When I was about to start building my first guitar I was very concerned with the whole humidity thing. As most of you know, I live in Slidell, Louisiana, about 25 miles south of New Orleans. My concerns were this; I basically live in the middle of a swamp, on the edge of a marsh, three miles from one of the biggest lakes in the country, and very close to the Gulf of Mexico. For most of the year our prevailing winds are from the south bathing us in warm humid Gulf air. From late spring to late fall the humidity rarely drops below 90% and usually hovers closer to 98% to 100%. I posted and posted about what to do and cried and whined like a baby and caused myself all kinds of stress to the point that I was not having fun. So I finally decided that I was not going to spend all kinds of outrageous money on trying to control the RH thus fighting a losing battle with mother nature. I now work within the opportunities that I have to do humidity sensitive glue-ups. I keep all of my components inside the house where the temp and RH are relatively stable. When I'm ready to do some work I carry my pieces out to the shop, perform the task and promptly return the components to the inside of the house. For the most part I consider humidity sensitive operations as glueing the bracing to the top and back and "closing the box" everything else I don't worry with too much and work all year round, keeping the parts inside the house except when I work on them. Since I decided to work in that fashion the stress went away and I began to have fun, lots of fun. I build guitars as a relaxing hobby and not to make money, that's why it's important to have fun. To aid me in monitoring the RH I built a wet/dry bulb hygrometer. I only use it when I am going to perform RH sensitive operations. The rest of the build process I don't worry about it and don't use the humidity measuring instrument. I built it for less than 20 bucks in a couple of hours. From what I'm told this homemade hygrometer is more accurate than anything costing less the $500. I'm told that digital hygrometers are grossly innacurate. In summary the operative word is "FUN" when I stray outside of that I must re-assess what I am doing!

Click on picture for close-up

David L

Hey Thio,

Welcome aboard. You might want to have a look at the link below before committing to a humidity control or humidity 'as you build' strategy.

http://www.larrivee.com/features/humidity.php

tommyboy

[Coach]

Ok now, I built myself a dry wet hygrometer, which tells me there is 53% RH in my home. My digital hygrometer says it's 27% RH. So which one is out of whack?

Outdoors it's 15 fahrenheit with 80% RH.

[kencierp]

Take your gauges a location with a know RH and test them for accuracy -- Like a mall or hospital etc.