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Normally I don't do any building at this time of the year since the inside humidity is too low. With the extended near zero temps lately it's even drier in the house than normal for this time. I'm a bit late because of the 3 guitars I'm trying to complete. The bodies are done and have been FP'ed. The necks are almost complete and the FB's fretted and glued.

Three days ago I essentially stopped all work in the shop because I can't get the humidity over 22%. I moved my console humidifier and all 3 bodies and the necks to a bedroom where I am able to maintain 40%. After 3 days everything seems to be properly hydrated again and presumably stable.

My question is...can I now take a neck and body down to the basement shop (22%) for 3-5 hours while final carving, neck setting and bridge gluing? I would, of course transfer it back to 45% after that time. How long does it take for the moisture to be sucked out to a dangerous level?

TIA

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JJ
Napa, CA
http://www.DonohueGuitars.com

That`s the same situation I`m having right now, JJ.
I`ve been jumping between the shop and build room. My shop is actually a garage bay, and although sealed and insulated, heating and hunidifying would be devastating to finances. Therefore it`s very dry out there.
My take on it is to do the work on the heavier/thicker wood in your basement, but the things like neck set and bridge gluing outa be done in the right enviroment to save changes in the initial setup that might come back and bite ya.
If the temprature is the same, you might seal up the body with a balloon to trap the humidity inside since you`ve already got your FP on, and go from there.
I`m sure the more experienced folks will chime in on this one.
Coe

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

Great idea on the balloon seal! If nothing else, it keeps the inside clean. Thanks, Coe.

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JJ
Napa, CA
http://www.DonohueGuitars.com

Bump

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JJ
Napa, CA
http://www.DonohueGuitars.com

I've been fogging my 20' X40' basement with my airless paint sprayer! Mostly directing towards my ceiling which are wooden floor and joists. LOTS of surface area to hydrate. It's just now showing signs of reaching stabilization after 3 days of several foggings per day. I think I was putting 3 gallons a day into the room. I'm gonna go down and check it again.

terry that is a great idea. i wish i had thought of it 35 years ago.

do you det any prolems with vapor condensing on wood or machine surfaces?

our canadian brothers and our northern provinces just refuse to keep their cold, arid, high pressure air masses where they belong and let them drift south to bother me.

I haven't seen temperatures above 15 in a week. I'm ready for spring! Clinton

Terry...once you get the humidity up to 40%+ how often do you have to spray to maintain that level while the furnace is going almost constantly? Do you heat with forced air?

I'd also be concerned about getting water on surfaces that I'd prefer to keep dry...what's your experience with this.

Let me repeat my original question...would there be any issue if I take a body and neck from the 45% room down to the shop at 22% for 3-5 hours and then return them to 45%?

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JJ
Napa, CA
http://www.DonohueGuitars.com

I've read that wood doesn't change it's moisture content rapidly. The article was talking about using a guitar outside in very wet conditions. My take is that it would take several hours to acclimate to the enviroment. So, working a few hours (3-5)and taking it back shouldn't be an issue. Clinton

Wood this thin will reponed to humidy chages pretty quickly. I once had an braced top that put in my car to show a friend at lunch, drove to lunch which was about a half hour away in a slightly different climate zone and the top had completey inverted it's arch. it reverted when I got back home, but I was totally surprised at how quickly it responded to the change. The weather was moderate at the time.

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Jim Watts
http://jameswattsguitars.com

Michael,

Hi there. I don't shoot over the machines, and no guitar wood is exposed (kept in a wooden locker). Ive been shooting just enough to get the joists moist, not wet. I knew it would take a few days this way. I'm home, so I can keep at it every few hours.

I was keeping wood for my next 2 guitars in my bedroom which is 45-50%. When it stabilizes down stairs, I'll commence building in earnest.

Hi JJ,
I haven't gotten it to stay put yet. LOwest was 29% and I overdid it to 60%, but it dropped very quickly. I do have forced air. I think today it finally started to stabilize. It dropped much slower. Now if I wasn't so cheap,I'd get a console humidifier It's about 12 degrees outside. Very "snappy" for several days now. Tough battle to keep it humidified.

Sprokett posted about a $360 humidifier that hooks into a water line, never have to fill it. I like that! Cigar shop humidor thing.

Regarding the unfinished neck visiting the low RH, Not sure what I'd do.... probably french polish it in a better environment. I know this cold dnap isn't here forever, but yours may there till spring

Bless you guys, happy building! Someone else chime in here...

JJ, you should be alright shaping the neck like you talking and even fitting the neck maybe but I'm not sure I'd glue much of anything until you humidity gets a little closer to normal. You can always go golfing but don't use a white ball

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Tickle your guitar daily, and it'll tickle you back.

JJ, I don't try and control the humidity in my shop itself, my shop is part of a very old structure and it would be impossible to control without industrial scale plant. I keep all of my wood, and instruments under construction, in a dedicated room in the house that has a dehumidifier (rarely if ever do I have to humidify). I have always just taken the stuff out to the shop, worked on it for however long then taken it back to the store. Never had any problems with this at all.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Thanks, guys. I'll be confident with doing the final neck carving and fitting in the shop now. I can always glue the bridge in the bedroom where the guitar will be residing anyway.

Hesh the shower curtained off shop area would work. If I had to start from the beginning, I'd do it but I'm almost completed and I'm actually looking forward to not building anything until the spring.

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JJ
Napa, CA
http://www.DonohueGuitars.com

for those who have forced air heat it is also in the best interest of your well being as well as your wood and instruments to install an in line humidifier. they are not that expensive and your problems are solved.

Michael...I have an Aprilaire on my unit and it doesn't even come close to providing the level of humidification that we need in this weather. Nonetheless, I will be looking into more robust units that may be able to do the job.

Another issue I have is that the walkout basement was never built with such needs in mind. Were I to do it from scratch, I would incorporate construction techniques that would insure better control in both summer (high humidity) as well as winter. Another one of those, "if I knew then what I know now"!

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JJ
Napa, CA
http://www.DonohueGuitars.com

JJ, I forget who it was who said this but it was a very experianced luthier. He said the single most important step in guitar building is where and when you glue the bridge onto the top! So if this is true definately glue your bridge in around 45% RH.
Everyone up north seems to be drying up and down here we have 97%

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Anderson Guitars
Clearwater,Fl. 33755

If you're moving bodies from 45% RH to an area that's much lower, you should check the amount of belly on the top, where the bridge & saddle will end up. Stew Mac has a simple tool with a dial indicator for doing this kind of thing. Very useful for neck relief as well.

Take a reading at 45%, write it on the top (the FB extension). Then take another reading in an hour or so, etc. What I have found is my "typical" belly is around .080" and it can drop quite dramatically even after a short period of time.

We're really only taking a few 64ths, but it adds up. This could cause your neck set to be off by as much as 1/16" at the saddle if you're not paying attention.

I'd imagine that FP would slow this down, but still worth measuring.

Steve