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Still learning more about humidity. Thanks by the way for the tips on the wet/dry psychrometer method. I learn everyday from this forum. Anyway, my question is this: The humidity in my uncles shop (not mine, or I would just bring it up to the correct humidity) is around 30%. This is very typical of the humidity all of the time here is southeast idaho, and this guitar will probably stay in the Idaho area all of its life anyway. Do I still need to build the guitar at around 40-45%?

Also, how big of a deal is the temperature. It is usually between 62-65 in his shop. Is this okay?

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Always remember you are unique......just like everyone else.

If the guitar is really going to spend its whole life in that same environment, then it would be good to build it at that RH. The thing is, a guitar lives a long time. If it's ever taken to a high humidity environment, it could have problems. Kind of a tough call. It doesn't get more humid than that in the summer there in SE Idaho?

As for temperature, my first concern would be glues curing properly. Wood glues like Titebond may cure fine at that temp, but you will need to heat the shop to more like 70 deg or higher for epoxies or hot hide glue. Personally, just to be certain, I'd want it to be at least 68 for all glues.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/

Hey James,

I'm building a guitar that's headed to Idaho right now, the coeur d'alene area. My impression is that the winters there are _bone dry_ and the summers can get humid...but then most people have their ac running during high humidity, which will tend to bring the humidity back down. So, in general, I think we're talking about a drier than average climate - not quite Arizona desert dry, but still dry.

Whether misguided or not, I've tried to do all my work with my shop in slightly drier than typical conditions...in the 35-40% range.

I realize that's not a solution to your problem, but it was my solution. Todd Rose and Stock both have good advice re. checking on the conditions and the potential for moving the guitar. That's why I built in 35-40 and not 25-30. Anyway...hope that helps.

Cheers,

Flori

I learned a humidity lesson this year. As some of you know, I play in a guitar ensemble, and we participate at the Carolina Reniassance Festival every year. This year, I took my #2 guitar out there. The weather was terrible for the first several weekends, and the guitar, which was built very lightly, was subjected to some extended exposure to humidity in the 100% range, including some direct precipitation. By the third weekend, it had developed some unusual undulations in the top. The fan braces were the low spots, and the top had bulged between them. Also, in the area of the open TB's, generated a smooth ridge line that ran from the end of the bridge up to the edge of the body at the neck. It really looked funny, it wasn't , but it looked funny. My thinking was that I shouldn't try to return it to low humidity too fast, so I took the strings off, and closed it up in a case, in my house, which is maintained in the 45 - 50% range, with a humidifier in the heat system. Over the weeks it's been in the case, it has recovered about 50%. The hills and valleys were reduced to lower levels. This weekend, I moved it to the shop, where the humidity is now about 40 - 45%, and noticed that, overnight, it had settled down even more. I am amazed at what a piece of wood will do. Nothing is loose, all joints are solid, as well as all braces and fans. I am amazed. I was afraid I might have trashed a pretty good guitar. My fault, totally, as I should not have taken such a lightly built instrument out in that weather. Guitars built on the edge shouldn't be exposed to the elements like I did. I used my #1 guitar for the rest of the season, and it did fine - rain or shine. Fortunately, we had more shine in the last 4 weekends of the festival. I didn't take pictures when it was at it's worst, or I'd have posted them, but the high areas were as much as 1/2" above the low areas. It looked like a carved top. As it looks now, it looks like it will recover fully. I figure, several days to a week in the shop should do it. Maybe I'll work on the French Polish some, while it's out of commission.

Just thought it was worth mentioning, in this discussion on humidity.

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Waddy

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Sound Clips of most of my guitars

Thanks everyone, and Waddy, thanks for the story. It helps to hear a real world example like that.

James

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Always remember you are unique......just like everyone else.