Climate control in old Gibson factory?

[sliebers]

I live in Minnesota, so I am very mindful of the relative humidity when assembling instruments, especially for the soundbox. My shop is not air-conditioned, so I try to build during the mid-humid months of spring and fall.

Something I've been curious about is how they dealt with this back at the old Gibson factory. Michigan is a similar climate to Minnesota (desert dry in winter and tropical in summer). In terms of the Loars, you see build dates in June, July, etc. This was back before air-conditioning was invented as far as I know.

How did they store their wood? Was the shop the same humidity as outdoors? Windows open, no climate control?

I'm just curious. I'm sure there's no way of knowing for sure.

Scott

[sunburst]

Surprising what we can get away with sometimes, isn't it?
It's something I've thought about. I suppose few people, if any, know for sure, but we can only assume that they did the best they could storing wood and using it in instruments, and dealt with the consequences... as we still do when we repair old Gibsons.
It would make sense that they did something to humidify the air in the factory in the winter - water evaporated the same 100 years ago as it does now, but as far as I know, there wasn't really anything they could do about high summer humidity.

I assume that big ol' smoke stack people are trying to save (because is says "GIBSON" on it) was attached to a boiler and that there was a steam heating system. Escaping steam, intentional or otherwise, from a heating system can go a long way toward helping to keep indoor humidity up in the winter.

[Bluetickhound]

As most everyone knows... Roger Siminoff and Lloyd Loar's widow were close friends. I wonder if the subject ever came up on their discussions or if he has any insight to offer.

[John Arnold]

It would not surprise me if Gibson warmed up the wood in the summer to lower the RH. At any rate, the general practice back then was to use wood that had seasoned for several years.
Martin would do critical glue-ups in a 'hot room', which served the dual purpose of drying the wood and giving more working time for the hot hide glue.

[sliebers]

Surprising what we can get away with sometimes, isn't it?
It's something I've thought about. I suppose few people, if any, know for sure, but we can only assume that they did the best they could storing wood and using it in instruments, and dealt with the consequences... as we still do when we repair old Gibsons.
It would make sense that they did something to humidify the air in the factory in the winter - water evaporated the same 100 years ago as it does now, but as far as I know, there wasn't really anything they could do about high summer humidity.

I assume that big ol' smoke stack people are trying to save (because is says "GIBSON" on it) was attached to a boiler and that there was a steam heating system. Escaping steam, intentional or otherwise, from a heating system can go a long way toward helping to keep indoor humidity up in the winter.

I would agree with you that the steam heating system in the winter helped keep humidity levels up. It's the summer months that would have been the biggest obstacle. Perhaps they had instruments assembled and ready for summer months and just did finish? That wouldn't help productivity however. Like you say, maybe they just did the best they could under the circumstances and dealt with the consequences. I was shocked to learn from a builder in Tennessee that builds year round with no air-conditioning in his shop. He just leaves the door and windows open. He said he's had no issues sending mandolins all over the country. I just don't think I could have that kind of luck.

[sliebers]

As most everyone knows... Roger Siminoff and Lloyd Loar's widow were close friends. I wonder if the subject ever came up on their discussions or if he has any insight to offer.

I would love to hear any insight Roger might have on the subject.

[Wes Brandt]

Interesting question.

Since the braces in the tops of mandolins run closer to parallel to the top grain and the backs have no braces, it's not near as much of a problem as it is for guitars where the braces go across the grain at up to 90 degrees.

The humidity problem is mostly about the difference in expansion and contraction with the grain vs across the grain which I remember is something like an average factor of 20 times.

When I was learning viol making in England (they have a wide brace or "plate" at 90 degrees across the back that the soundpost sits on, just like a flat back bass) ...the method was to heat the back over an electric heater (could be any heat source) to dry it out on the spot… then immediately glue on the plate with hide glue that was on the thick side… not particularly precise but you probably got good at judging it …the last thing you wanted was a reverse bow with that plate area… it completely kills the sound.

With mandolins, the humidity danger is where the grain of the sides crosses the top and back plates the closer you get to the tail and neck blocks… but that would be one way of dealing with it in humid summers.

I'm pretty sure all Gibson flat top guitars were built with a significant arch in the top. Another way to compensate for humidity… you don't want sunken tops either, sound wise.

Now I have a small room and a very precise digital humidity controller that I plug my dehumidifier or humidifier into depending…

[sliebers]

Interesting question.

Since the braces in the tops of mandolins run closer to parallel to the top grain and the backs have no braces, it's not near as much of a problem as it is for guitars where the braces go across the grain at up to 90 degrees.

The humidity problem is mostly about the difference in expansion and contraction with the grain vs across the grain which I remember is something like an average factor of 20 times.

When I was learning viol making in England (they have a wide brace or "plate" at 90 degrees across the back that the soundpost sits on, just like a flat back bass) ...the method was to heat the back over an electric heater (could be any heat source) to dry it out on the spot… then immediately glue on the plate with hide glue that was on the thick side… not particularly precise but you probably got good at judging it …the last thing you wanted was a reverse bow with that plate area… it completely kills the sound.

With mandolins, the humidity danger is where the grain of the sides crosses the top and back plates the closer you get to the tail and neck blocks… but that would be one way of dealing with it in humid summers.

I'm pretty sure all Gibson flat top guitars were built with a significant arch in the top. Another way to compensate for humidity… you don't want sunken tops either, sound wise.

Now I have a small room and a very precise digital humidity controller that I plug my dehumidifier or humidifier into depending…

Wes, those are good points. I didn't think about the almost parallel braces of mandolins to the top grain and no braces on the back. It would certainly be more significant on guitars where braces cross close to and on perpendicular to the grain.

I've started de-humidifying in a small room as well. It seems like the wood equalizes in about a week depending on the thickness and species.

[allenhopkins]

...I'm pretty sure all Gibson flat top guitars were built with a significant arch in the top. Another way to compensate for humidity…

Do you have info re: this? The pre-WWII Gibson guitars I own don't seem to have any arch induced in the top (LG-3/4 and tenor guitar).

[barney 59]

It would not surprise me if Gibson warmed up the wood in the summer to lower the RH. At any rate, the general practice back then was to use wood that had seasoned for several years.
Martin would do critical glue-ups in a 'hot room', which served the dual purpose of drying the wood and giving more working time for the hot hide glue.

I thought the general practice now was also to use wood that had been seasoned for several years.
They could have just heated the room to lower the humidity and tough luck for the workers...or maybe they could have used an AIR CONDITIONER which came into use about the same time that Gibson built a factory. If I owned a wood working factory I would have been first in line when Carrier came up with air conditioning! If you want to think "old world" you have to go back to about 1830. Gibson is solidly well into the industrial revolution .

[David Houchens]

A little off base here maybe, but many of these instruments survived homes with only wood heat, no insulation and maybe a window fan if they were lucky. My father said he remembered more than once waking up with a light skiff of snow on his bed sheets from blowing winds.
I do everything I can to keep my entire shop between 40-50 percent, and have good luck with it. Still I wonder if I knew where an instrument was headed, should I build it more toward the average climate of where its headed?
I guess it's up to the purchaser to keep it in the best humidity they can.

[pheffernan]

I've read that Chris Stanley deliberately builds in low humidity environments in neighboring Wisconsin so that his mandolins won't crack and won't need humidification.

[barney 59]

A little off base here maybe, but many of these instruments survived homes with only wood heat, no insulation and maybe a window fan if they were lucky. My father said he remembered more than once waking up with a light skiff of snow on his bed sheets from blowing winds.
I do everything I can to keep my entire shop between 40-50 percent, and have good luck with it. Still I wonder if I knew where an instrument was headed, should I build it more toward the average climate of where its headed?
I guess it's up to the purchaser to keep it in the best humidity they can.

Or coal, oil or gas. Very likely coal in a lot of regions. 19th century museums had a difficult situation in those large buildings without insulation,single pane glass etc. When they raised the temperature,particularly in the very coldest weather they would create a condensation problem on the exterior walls and windows,ceilings and roofs when the heated air hit dew point when it came into contact with the cool surfaces. It was really tough on the items that they were trying to preserve. I've seen charts about this and going from flawed memory if the temperature was somewhere around 0 F outside they could heat the room to maybe 30 or so degrees and the RH would hover around 40% with very little or no problem with condensation but this was well below the comfort zone for people. The solution was to create micro climates --display cases, dioramas behind glass,pictures behind glass etc. I always thought that it was a security thing, protecting the stuff from people but I guess nutty people with hammers hadn't been invented yet, it was to protect the stuff from moisture mostly. It's pretty obvious that for the first 5,000,000 years of our existence people were much more tolerant of extreme temperatures than many of us are today. A factory would have many of the problems that the museums did but maybe even more extreme as the buildings tended to be much more cheaply constructed than say the Carnegie or the Met but likely to have a similar volume of space. So would a factory tend to keep the temperature intentionally cool in the Winter and extra hot in the Summer if what they were building would be adversely affected by extremes of humidity and the work force tolerate it? Did they create climate zones for certain operations? Maybe. Someone already mentioned Martin's "Hot" room --some poor sot had to work in there!

As for personal instruments I've often wondered what is better? Let them live in temperature or humidity levels closer to environmental conditions or take them from heated or air conditioned environments directly out into the environment? I'd think bouncing them back and forth like from your air conditioned car to the parking lot jam and then back to the car would be worse for the instrument in the long hall than letting it live in or closer to the what the natural environment is dictating at the time.

[Mandoplumb]

I'm not a builder nor do I play one on TV, but don't braces on ovel hole mandolins run cross grain?

[John Arnold]

The pre-WWII Gibson guitars I own don't seem to have any arch induced in the top (LG-3/4 and tenor guitar).

The larger Gibsons definitely had arched tops in the 1930's. Gibson started arching the Jumbo size ('round shoulder' dreads) around 1936, and the L-00 size (14 3/4" lower bout) had arching a year or two before that.

[Wes Brandt]

Do you have info re: this? The pre-WWII Gibson guitars I own don't seem to have any arch induced in the top (LG-3/4 and tenor guitar).

One way you can tell that I've seen, besides that they ARE arched is they must have arched the braces after they cut them into the usual triangle shape ...so that they get narrower towards the sides as they taper in height… at least the x braces and two main tone bars do.

Probably more information than you wanted here….

http://theunofficialmartinguitarforu...1#.VZHKIuvSHFI

http://theunofficialmartinguitarforu...1#.VZHK5OvSHFI

[Timbofood]

"Back in the day" I think they called climate control something like "windows".

[pfox14]

I believe that Gibson stored raw wood on the first floor of the old Parsons St. factory, which was actually half underground. I would think that the humidity would have been higher than 50% in a partial basement. It's possible that after they cut the blanks, they would let those sit in a drier environment or even put them in a kiln, before being worked on during production.

[stevedenver]

Interesting question.

....

I'm pretty sure all Gibson flat top guitars were built with a significant arch in the top. Another way to compensate for humidity… you don't want sunken tops either, sound wise.

Now I have a small room and a very precise digital humidity controller that I plug my dehumidifier or humidifier into depending…

great info
and you are correct about flat tops with an arch. in 2000 I spoke at length with the shop manager of the Bozeman plant, and he explained to me how at that time, Gibson had completely "redesigned" the acoustic line to return to original specs, and the arch in top and back was something he mentioned specifically.

More to the point, the new model acoustics Gibson I played in the Nashville artist relations shop were ...superb...entirely different from those I have played from the 60s to the 80s-not overbuilt and dead, but alive. (this coming from a Martin guy. Modern Gibsons are superb imho.

I think a very important point about factory humidity...is that wood was seasoned for many more years before use. This, as I understand things, was due in large part to relatively consistent production numbers. The really big boom in production numbers came in the 60s.

Even then, the wood was seasoned many years prior to use. This alone tends to eliminate a great amount of reveal "wood that doesn't want to be an instrument".

When I was building lutes and guitars, starting in 1970, my wood suppliers selections were routinely seasoned 20-50 years! I don't know if this was unique to my supplier, a local guy in Denver with a barn of simply stunning exotics as well as top spruce, but that was my experience.

[kjbllc]

interesting, also consider that pre 1800's instruments, violins, were kept all over europe and american and elsewhere, with no humidity control and extreme rises in temps and humidity. Of course there were seam separations and other problems, they even came up with metal violins for the islands, maybe a lot more work for luthiers! but all in all they held together pretty well, imagine shipping in a stage coach or ship , I bet a lot of instruments arrived in bad shape.

[sunburst]

...but all in all they held together pretty well...

No, they've been put back together pretty well, many of them quite a few times.
Violin family instruments have built-in design features to deal with wood movement: overhanging plate edges, glue joints meant to fail before the wood fails, arches and curves... Even so there are lots of repaired splits and cracks in virtually all old violins.

[kjbllc]

Yes you are right about that , I think there are only a few strads that are considered fairly original, I was thinking more along the lines of , while they were being used by the masters, and everyone else in orchestras, on the road , on the farms in the city's , being played "years ?" at a time without repairs and being played hard. paganini for instance was ," played like the devil ", all the while with no temp control, and probably wide temp differences.

[Wes Brandt]

interesting, also consider that pre 1800's instruments, violins, were kept all over europe and american and elsewhere, with no humidity control and extreme rises in temps and humidity. Of course there were seam separations and other problems, they even came up with metal violins for the islands, maybe a lot more work for luthiers! but all in all they held together pretty well, imagine shipping in a stage coach or ship , I bet a lot of instruments arrived in bad shape.

However, the main humidity related cause of damage to instruments in my experience comes from constantly heated buildings in the winter when it is clear and cold over a extended period where the humidity can drop into the teens or 20s ….keeping buildings at a constant 70-80 degrees in winter is a more modern thing.

[Wes Brandt]

I sometimes think people confuse aged, "seasoned" or dry and ready to use, with daily fluctuations in humidity where a seasoned spruce top ready for bracing in a shop whose humidity is 70 % would definitely be considered too wet to glue braces…

However, I can turn on my dehumidifier set to 43% and hang up the top so the air circulated around it and 24 hours later it is ready for bracing. I might give it 2 days for a rose wood back.

You can make a simple humidity gauge by cutting two pieces of scrap top spruce… say 1/8 x 1 x 6" with the grain in opposite directions in each piece and glue them together with epoxy at the humidity you want to "record" …the resulting sandwich will quite quickly bend in one direction or the other depending on the humidity changes and when it's straight… it will be at the same humidity at which they were glued together …

[sunburst]

I sometimes think people confuse aged, "seasoned" or dry and ready to use...

Yes, they absolutely do. People will say something like "this wood has been drying in a barn for 150 years!" What they don't realize is; if the RH in the barn is higher than 50%, when you bring the wood into the shop (where it is 50% RH) it will start drying.
Wood is hygroscopic, and the moisture content (MC) of the wood fluctuates with RH no matter how long it has been cut.
The wood from the barn is more "seasoned" than newer, drier wood, but it is not drier. It may have been seasoning in the barn for 150 years, but it hasn't been drying, it's been fluctuating up and down in moisture content.

BTW, according to this graph, the MC of spruce only changes from about 13% down to about 8% if you lower your shop RH from 70% to 45%. We are fortunate that MC of wood is more stable over the normal range of RH in which we work than it is at the extremes of RH.