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I live in one of those parts of the country where dehumidifiers struggle 3/4 of the year to keep the shop at a good RH, and humidifiers struggle that other 1/4 of the year. We're in that time now, and my humidifiers aren't keeping up. I'm lucky to keep the shop up to 30% RH, so I've turned to alternative activities in the shop.

I'm really thankful that I set myself up with CNC equipment and software back when I was employed and could afford it. It paid for itself years ago with my banjo building, but it's really paying off now with the continued lock down and me looking for things to do. There are a lot of cool jigs and fixtures available out there that I want but I can't really afford on Social Security wages, so I've been hitting the CAD computer lately and have cranked out a bunch of useful jigs.

First, I did a neck centering jig like a lot of them you see out there. Not as elegant as the commercial versions, but it works. I also made a fingerboard/neck index pin drilling jig (that matches up with my CNC fingerboards and necks). Built an end graft vise/template holder. A bunch of specialized vacuum fixtures. Re-did my binding cutter. Etc.

It's been fun and productive. Used up a bunch of scrap materials, and turned them into useful things. Kept myself busy in the days of low RH. Didn't rip off anyone else's designs--tried to find different ways of doing the same thing. Not necessarily improvements, but they work for me. I look forward to getting the opportunity to use some of this stuff!

Dave

There’s always sweeping if you run out of projects!

Build tools. Reorganize the shop for more efficiency. Do guitar or furniture repairs. Seek out sub-contracting parts or assemblies (doesn't have to be guitars). Do volunteer work one or two days a week? Teach classes.

Cessna Aircraft made furniture when planes weren't selling. Boeing made boats. Beech Aircraft built cars. Be versatile and adventuresome.

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"Act your age, not your shoe size" - Prince

Most of the time you don't need to worry about humidity anyway. Bracing is the only time it's really critical (note: the bridge is a brace). Box closing is best done at the control level as well, but not essential since you can control the stress distribution by the order you apply clamps. And if the plate is potato chipped due to low humidity, then you probably braced it in too high of humidty anyway.

Gluing the fingerboard extension to the soundboard should be done in low humidity if using ebony, since its ridiculously high expansion rate can cause soundboard cracks due to it shrinking much faster than the soundboard in low humidity later.

Leveling fret ends should be done in as low of humidity as possible, since it's annoying if they poke out when the humidity drops later, but no problem if they're inset a bit in high humidity.

If you build instruments with friction peg tuners, the holes for those need to be reamed in middle humidity so they don't go too far out of round in either high or low humidity.

My shop is in my unheated basement, so right now it isn't too bad down there yet. 55 degrees, and 40% humidity. Oddly, upstairs it is 66 degrees and 45% humidity. I used the same gage. I don't get it. I would have thought that the humidity upstairs would be lower than the basement. The water even starts flowing into the sump pump around the end of November, and stops in the spring. So you would think....

I only do quick tasks downstairs when it gets colder, and it is great for roughing an arch top, or a cello by hand. I need stock for a cello back and sides, and an arch top belly, and sides. If I got that, I could work roughing them. I do planning a lot in the late winter. I have a car model, and some oil paints to play with too, for something really different.

After years of CNC machining, I'm back to the days of hand tools. I like using planes, gouges and scrapers. The hardest task by hand that I've found on guitars, even more so than on violins, is the purfling and binding. I used a Dremel on the last violin with double purfling, and I am sold on that over the knife. Maybe I'll see how that can work on binding.

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Why be normal?

The maker I met in Majorca said he only had a couple of months of 'good' humidity during the year for bracing and closing the box. For those months he worked 16 hours a day. The rest of the time he made rosettes, roughed other parts, put on bindings and did finish work.

Yea, I would probably focus on process improvements as well. Depending on how you do your material sourcing you could also batch out a bunch of parts or part blanks. Personally, I find the milling process total drudgery, so If I sourced materials differently, I would probably spend a week just grinding out as many brace blanks, fret board blanks, bridge blanks and necks as I could. Of course, the down side is that's a lot of money to have sitting around in materials.

In the wintertime I keep my shop at around 50F and that helps keep the humidity in the 35% to 40% range. Around here we get enough rainy days, even in the winter so I can do braces, backs and tops if I need to.

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Steve Smith
"Music is what feelings sound like"

When I lived in Knoxville, I never had the problem, but my shop was on my house HVAC. My shop in NC has a small gas heater, and I keep my shop at around 60-65 this time of year, and it usually sits at the 35 to 40 percent range, but during this recent cold snap I had a hard time keeping it above 25 percent.

Dave

The cold snaps are tough, the humidity dropped down to around 30% in my shop. I keep the shop at 50F with one of those portable oil filled electric heaters.

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Steve Smith
"Music is what feelings sound like"

Dave that sort of RH seems extraordinary. Here in the southern UK we are at about 60 and later in the year it will often be at 80.

With a fairly well sealed shop an ordinary domestic dehumidifier can get me down to 45 to 50 for the important glue ups.

But as people have said it is useful to take a bit of time out to clean the shop, think about processes, improve jigs and maybe do something completely different. I have on my list to make a slightly better headstock pattern and an improved circle cutting router jig.

First though to finish an acoustic build which is almost there!

Enjoy your time out. Dave M

Yeah, I usually have no problem keeping the shop at 45% or so, but living in the middle of a North American rain forest, it can be tough year round--about like what you have in the southern UK. When the winter weather hits, it gets really dry when you include the impact of heat in the shop. Now that temperatures are back to a seasonable level, my RH is back in the high 30s.

Good luck with your acoustic build!

Dave

50 F is a bit on the cool side for some glues. The Titebond bottle says that the air, glue, and material, have to be at 45 or above. Evaporation can drop the glue temperature if the humidity is low. If the squeeze out ever looks chalky you're probably pushing things, and could end up with bad glue lines. DAMHIKT

From what I've seen you get into far more problems from building at too high humidity than too low. I try to keep the shop between 40%-45%, although short excursions above or below that by 5% or so are probably OK.

The key to controlling humidity is reducing air and moisture infiltration. Basement shops are the worst; concrete and mortar are essentially transparent to moisture, and have to be sealed on the outside to make an effective barrier. Again, DAMHIKT

It's very similar here in Virginia too. It's 58deg today and it was 13deg just the other day. I'm sure we will get one week of below 10deg. It snows but the snow lasts only a few days or couple weeks at most then melts and the RH swings again.

What I did? I payed a lot for spray foam insulation and now a single small humidifer is good to go. Of course it depends on the size of the shop too. Mine is two stories about 25x15 or so.

I typically warm things up a bit before I glue anything, at a minimum I'll use a heat lamp but I also have a large AC/Heat window unit. Haven't had any issues if I warm up the shop for a bit while I glue then shut the heat back off when I'm done.

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Steve Smith
"Music is what feelings sound like"