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Henning
07-18-2017, 04:58 AM
Hello, I donīt know if this is the right Place to post this question. But on the other hand where would so be?
If I buy an ukulele from South east Asia, probably made in a humidity of about 65 - 70%. Could I somehow adopt it to North European or American/Canadian Winters over a period of time ( a few yeas) where the humidity is a more normal 50% over the year with maybe Winters of 30% and summers with 70% air humidity?
Or is it condemned to crack into pieces?

Kind regards

Michael Smith
07-18-2017, 05:32 AM
You should not buy a ukulele made at 70% humitly. There are no factories in Asia or anywhere else that do not control humitity to around 45%. To not do so would quickly be business ending. That said I have been asked to repair instuments that were made in too high humidity. They were made in the USA by small time builders who for whatever reason didn't take the care necessary to contol humidity. I''m not talking about anyone on this forum. So if you are looking at a botique builder in Asia who does not take measures to contol humidity as Jim Cramer says "dont buy, don't buy"

Henning
07-18-2017, 05:40 AM
That said I have been asked to repair instuments that were made in too high humidity. They were made in the USA by small time builders who for whatever reason didn't take the care necessary to contol humidity.

Thanks, I suppose it would necessiate some precautions to repair such instruments. Do you treat them as if they were built in 50% humidity or how did you do that?

cyber3d
07-18-2017, 07:30 AM
Not to hijack this thread, but, (to paraphrase) you say a big shift in humidity from factory to end user can cause cracks. Is it also really bad for a uke to see daily big swings in humidity? And how much of a swing becomes problematic? My room goes from 40% to 75% throughout the day! I'm concerned for my solid spruce top!

Michael Smith
07-18-2017, 11:57 AM
Humidity changes will kill just about every instrument ever made at some point. If this happens in a week or 400 years depends on how well the owner/owners contol and or limit these changes. I believe every owner of a valuable wooden musical instrument should keep their instrument in a fiberglass or abs case with a couple Boveda 49% humidity packets. Take it out to play then put it back when they are done. Not all humdity control products are the same. The Boveda packets contain certain salts that release moisture with humidity goes below 45% and suck up moisture when humidity goes above.

Twibbly
07-18-2017, 12:56 PM
Humidity changes will kill just about every instrument ever made at some point. If this happens in a week or 400 years depends on how well the owner/owners contol and or limit these changes. I believe every owner of a valuable wooden musical instrument should keep their instrument in a fiberglass or abs case with a couple Boveda 49% humidity packets. Take it out to play then put it back when they are done. Not all humdity control products are the same. The Boveda packets contain certain salts that release moisture with humidity goes below 45% and suck up moisture when humidity goes above.

This is why I have no desire to buy more expensive ukuleles than what I have (my most expensive one is an Outdoor Ukulele tenor, for reference - no worries about it cracking!). I live in a desert. We get wild swings in humidity at least once a month or so, and I don't currently have the means to even buy hard cases for the ones that would benefit from humidity control.

Henning
07-19-2017, 09:15 AM
We get wild swings in humidity at least once a month or so, and I don't currently have the means to even buy hard cases for the ones that would benefit from humidity control.

Now if those are solid tops, why donīt you? (!)

Well, Iīm sorry.

Henning
07-22-2017, 07:01 AM
Iīd say a string instrument that canīt withstand 30% humidity up to maybe 80% of humidity. at least during shorter moments, for playing, rehearsal, an evening in a concert hall etc., isnīt of very much use.

sequoia
07-22-2017, 08:05 PM
Iīd say a string instrument that canīt withstand 30% humidity up to maybe 80% of humidity. at least during shorter moments, for playing, rehearsal, an evening in a concert hall etc., isnīt of very much use.

I agree Henning. Couldn't have said it better. Perhaps the instrument needs to be transported in a perfectly perfect humid environmentally controlled case and then brought out of its perfect environment into a performance hall that has perfectly matching humidity where it is played and then put back into its perfect case.

But you have to understand, ukuleles cracking, exploding, racking, warping, twisting and basically coming unglued and flying apart is the ultimate nightmare of people who build these things. Thus the obsession with humidity. Wood gonna do what wood gonna do. This isn't always controllable and that is what keeps us up at night. The ultimate unspoken truth is that all delicate acoustic wooden instruments are ephemeral, living objects and just like the people who play them, they are ultimately going to die. I call it a terminal case of dynamic deformation over time. Sort of like growing old. Something has got to give eventually.

Luthier nightmare: 3:30 am Pacific Time Zone: Phone rings: "Hello (groggily)..... Are you Rick?... Mmmmm.... what?.... I'm calling from Oslo and I have an ukulele that has cracked in half and has you name on the label! What are you going to do about it?. I want my money back!.... (wake up in a cold sweat screaming silently).

southcoastukes
07-29-2017, 05:45 AM
Let me give some insight here into building in tropical humidity. First, this is not meant to contradict Michael (what a font of knowledge!) or any other posters here who look down on this sort of thing. But their analysis is a bit incomplete. They assume the basic techniques of building are universal. Unfortunately so do some new builders in these tropical environments. But building techniques that work when an instrument doesn't travel are problematic when shipping instruments out of high humidity areas. That’s what isn’t understood; that’s what causes the problems.

So first, look at where the typical construction falls short when building in high humidity and shipping to a lower environment. You have to look at the instrument piece by piece. The most problematic area by far is the hardwood back. A hardwood top is not much better. Sides can split but their movement is not as restricted, so damage is relatively rare. Necks just need to be made of slow dried stable timber. The most straightforward examples of how to build are in places like Veracruz and Northern South America. Various instruments there have bodies that are simply made out of a hollowed solid block. The soundboards aren’t hardwood but softwood, allowing much greater flexibility. Not only are the thicker body elements more resistant to warping, but glue joints are cut down as well (another topic).

We have always built in Central America. Our first shop, one we built in for almost a decade, was not only not controlled for humidity, the roof leaked as well. During the rainy season, we had to often be at 100% humidity. Having designed our way around that sort of environment with solid wood furniture exports, we felt that with the narrow stock needed for Ukuleles there was no cause for concern. The first prototypes showed us our mistake as a couple of Soprano prototype backs cracked during their first winter. We had overlooked how the thinner material of an Ukulele back would be more susceptible to splitting than what we had been using for furniture. Okay, it was 20% with the central heat, but if we could do that, so could someone else.

We didn’t want to try to market the hollowed out solid wood body; there’s nothing wrong with it, but in spite of being a very refined technique in good hands, it has the flavor of something crude up north. So we wanted to build in a more traditional “European” style and hit on a way to do that.

Rene LaCote was perhaps the premier builder of Romantic Era Guitars, and favoured a Cypress lining on his backs. He did it for a “sweeter sound”, but of course it solves the problem of the weakest point of tropical construction in European style. It does affect both the depth of resonance and the sound, but the sound quality was not inferior, just different. Some Spanish guitars are still built this way; our builder was very familiar with the construction and enthusiastic about it. It took no time at all to adjust the other parts of the body to the parameters of the stiffer, almost Australian style back.

We ended up using different wood for side material: solid, stiff and slightly thicker than normal. Of course good “bendability” was extremely important as well once you go that route. We used carbon fiber reinforced necks. Soundboards needed a curve to allow for movement (a bit on the backs as well). We used German Spruce soundboards in the beginning, but in the end, just to be on the safe side, went to an extremely stable soundboard: Alaskan Yellow Cedar. It not only moved less (better intonation) but we ended up with a sound that paired better with our stiff bodies than we had had with German Spruce.

That construction served us for years: instruments went to all sorts of climates and never gave us a problem. So the point in all this is that once, instruments were built in their environment for players in that environment. Now that builders are shipping all over the world, it doesn’t rule out certain building conditions; it just means you need to do a bit of engineering. That’s all the “golden 45%” rule tries to do. It just tries to hit a “median” humidity so an instrument can travel through a certain (though still limited) range of environments. A 45% building environment, for example, won't cause immediate problems for a customer in a place like here in Louisiana, but with our 70-80% typical humidity range, it's less than ideal.

I’ve always thought that one great feature of Ukulele design is portability. And that means it should be able to withstand an even greater range of humidity than other stringed instruments. But you don’t necessarily have to control your building environment to do that. Our construction, for example, was one solution that allowed for even greater portability than standard design. Just think about your instrument; think about your environment; think about your woods; don’t rely on traditional formulae; find your own.

P.S: We are working with a new shop now as our previous builder has retired. It is causing some adjustments and taking time to reset some parameters. This fellow has taken the modern approach and has a humidity controlled shop. Re-adjusting some of the design technique to the new environment (the kind y’all are used to) has been a surprisingly long process. Almost done now, but sometimes I kind of wish for the old days of the wild tropics.

cyber3d
07-29-2017, 08:56 AM
Fantastic insights Dirk Wormhoudt!

sequoia
07-29-2017, 07:27 PM
Thank you for the informative post Dirk. Very well put. This stuff always interests me. I build in what is known as a "Mediterranean Climate" which basically has the worst of both worlds: Monsoonal rain for half the year and then total dryness with no rain for half the year. Basically 100% humidity followed by air so dry it will make your lips crack... I once heard the bromide: If you have to build in adverse humidity, build wet because shrinkage is better than expansion. In other words: An uke built in the Amazon and sent to Arizona is better than an uke built in Arizona and sent to the Amazon. In other words: Shrinkage is less damaging than expansion. The prevailing "wisdom" is that the expanding uke will "explode" the construction forcing all the joints and doing far more damage than shinkage. In other words: The uke built in the Alabama jungle and sent to Libya will survive better than the Libiyan uke sent to Alabama. Any truth or validity to that?

Michael Smith
07-30-2017, 08:11 AM
Building at 90% humidity then take it to a place like California where we get in the 20% humidity and not have the frets jabbing you and other serious issues Really? I'll stick with building at humidity levels used by Taylor, Martin and other fine instrument makers who have been building for a hunderd years. I've had to reapair too many instuments that were made in high humidity.

Henning
07-30-2017, 10:24 AM
A couple of years ago I made new struts for the top and back of an ukulele in solid mahogny. I did thus during winter when the humidity is between 30 - 40% and oftenly rather closer to 30%. I then realized that 30% is rather much on the dry side and told the local luthier this but he just smiled lightly and answered: "perfect, this will be perfect!"
But the plates of this ukulele is 60 to 70 years of age and most likely they donīt move so much.

southcoastukes
07-30-2017, 02:18 PM
Thank you for the informative post Dirk. Very well put. This stuff always interests me. I build in what is known as a "Mediterranean Climate" which basically has the worst of both worlds: Monsoonal rain for half the year and then total dryness with no rain for half the year. Basically 100% humidity followed by air so dry it will make your lips crack... I once heard the bromide: If you have to build in adverse humidity, build wet because shrinkage is better than expansion. In other words: An uke built in the Amazon and sent to Arizona is better than an uke built in Arizona and sent to the Amazon. In other words: Shrinkage is less damaging than expansion. The prevailing "wisdom" is that the expanding uke will "explode" the construction forcing all the joints and doing far more damage than shinkage. In other words: The uke built in the Alabama jungle and sent to Libya will survive better than the Libiyan uke sent to Alabama. Any truth or validity to that?

Hello Red,

As all my experience has been just one way (humid to dry), I can't say for sure. My unproven guess would be that for the opposite, again you'd look for woods with little movement and put just the slightest of curves on the front and back, figuring they'd go up.

But in your circumstance, trying to control your environment to an average humidity is by far the best way to go. We also had 6 month rainy and dry seasons, but the "dry" season didn't get much below Louisiana humidity until right before the rains came back. Nothing as drastic as you're describing.

Even with that, we actually considered building for only 6 months of the year, but there are always things that get in the way, and to keep from running into the rainy part of the years by accident, you'd almost have to take that down to a 3 month schedule per year.

southcoastukes
07-30-2017, 02:40 PM
Building at 90% humidity then take it to a place like California where we get in the 20% humidity and not have the frets jabbing you and other serious issues Really? I'll stick with building at humidity levels used by Taylor, Martin and other fine instrument makers who have been building for a hunderd years. I've had to reapair too many instuments that were made in high humidity.

Hello Michael,

Let me apologize if my first post came out like I was throwing some kind of sarcasm your way. That was definetly not my intention. I truly meant to complement your knowledge and with the caveat of my first post, don't disagree in general with anything you said in your first two posts.

However while Taylor & Martin are to be admired for what they do, high end volume production allows for the sort of investment in things like environmental controls that a small operation may not find practical. I'm sure, for example, they have some machinery that isn't practical for you, and protocol for volume that's not very apropos of your methods either.

Our first luthier was from a family that has been building instruments over three times longer than Martin & Taylor. He has built for some of the finest guitarists in the Americas including, for example, Alirio Diaz. And while it's true Martin & Taylor, in their relatively short time, do likely have considerably more knowledge about shipping into other climates, it's not like Omar was in the dark about the challenges of that sort of thing.

But let me explain a bit more (that first post was pretty long). For most of what we did, the instruments came up unfinished. The storage, set-up and finishing areas up here in Louisiana were climate controlled (I kept them around 50%). After a few weeks I could see what sort of movement there might be. That allowed me to finish, fix the bridges and set things up after everything had settled down. It also allowed me to go over with Omar anything we might want to do to fine tune the plates next time around.

And yes, the fret ends would have to be dressed. It wasn't any sort of major work, just another part of finishing things off. So you are right that going directly from Central America to you without the intermediate stop would have involved both fret dressing and a new set-up. That would have been it, though.

Sorry again for any misunderstanding.

robedney
08-01-2017, 07:39 PM
Well said Mr. Wormhoudt. And if you think ukes have problems you should try violins! I came to think of them as little boxes under unending tension constantly threatening to self-destruct, particularly using traditional hide glue (we make carbon fiber violins exclusively these days).

However, based on long experience with wood, I would venture that most all wood ukes will handle a good deal more than a survey of UU posts would suggest. A well built uke -- and there are some surprisingly well-built instruments that are built overseas and cheap -- will handle most real world humidity shifts without a problem so long as common sense is observed.

Not mentioned here is the issue having to do with the proper drying/seasoning of wood stock. No matter the humidity in the maker's shop, if a fingerboard is made up from unseasoned wood it's going to shrink and the frets are going to hang out on the ends. For top and back plates, slow "stick" drying over time will produce fewer cracks than will accelerated kiln drying (over the life of the instrument). A lot of traditional builders have a real feel for drying wood and selecting it -- something that doesn't lend itself to a factory setting.

Michael N.
08-01-2017, 09:59 PM
Thank you for the informative post Dirk. Very well put. This stuff always interests me. I build in what is known as a "Mediterranean Climate" which basically has the worst of both worlds: Monsoonal rain for half the year and then total dryness with no rain for half the year. Basically 100% humidity followed by air so dry it will make your lips crack... I once heard the bromide: If you have to build in adverse humidity, build wet because shrinkage is better than expansion. In other words: An uke built in the Amazon and sent to Arizona is better than an uke built in Arizona and sent to the Amazon. In other words: Shrinkage is less damaging than expansion. The prevailing "wisdom" is that the expanding uke will "explode" the construction forcing all the joints and doing far more damage than shinkage. In other words: The uke built in the Alabama jungle and sent to Libya will survive better than the Libiyan uke sent to Alabama. Any truth or validity to that?

It's the opposite. Going from wet to dry is the greater danger. Many years ago I worked in repair (when brick and mortar shops existed). Sudden plummeting of R.Humidity always meant an increase in repair numbers. In fact I remember at one shop 3 bridges had flown off overnight. That kind of sudden plummeting of RH is always associated with a very cold snap, frequently with snow. Summer months and RH frequently climbs into the 70's here in the UK but in terms of repair the summer months were always the quietest times.
The answer to all this is to build for the appropriate humidity. The small builder can do that by conditioning wood in a small enclosed place. It's far easier to control humidity in a large cupboard than it is in a large room. I don't use it much for RH control but I have a UV light cupboard, used frequently for drying varnishes and sun tanning wood. The RH inside the cupboard is around 10 to 15% lower than the external atmosphere. That's in a cupboard with deliberate air baffles. The swing I could achieve would be much greater if I sealed the cupboard. I have to place a baby bottle warmer in the base of that cupboard to maintain RH in the 40's range. It's not the UV that lowers the RH but the heat given off by the light. The alternative is to use one of the smaller dehumidifiers designed for small enclosed spaces, although having never used one I can't tell you how effective they are. Heat does work.
Given that we work with very thin timber any wood conditioning is pretty quick. You can place the wood inside the cupboard for 8 hours, remove and immediately do your glue up. If you wish to increase RH then you need to switch off the heat and introduce some sort of gentle steamer.
It's a touch more time consuming to build using this method but it is far better than taking your chances with inappropriate humidity.

hoosierhiver
08-02-2017, 03:23 AM
Aside from building in high humidity, another common problem with ukes made in Vietnam is that the builder is often a small outfit ( and poor) and they don't have the resources to buy wood and let it dry for the proper amount of time, so they make a uke out of green(ish) wood which later warps and splits as it dries.

sequoia
08-02-2017, 06:47 PM
Aside from building in high humidity, another common problem with ukes made in Vietnam is that the builder is often a small outfit ( and poor) and they don't have the resources to buy wood and let it dry for the proper amount of time, so they make a uke out of green(ish) wood which later warps and splits as it dries.

I think there is a lot of truth to the above. Who has the time to condition wood and cure it properly when you are building in the third world You have the wood then start making ukes. Proper seasoning takes time and in the sweat shops of Indonesia (and South east Asia), who has the time? Time is money. Personally I think building with "green" unseasoned wood is a bigger part of this problem than changes in humidity. That said, take an uke built out of green wood in a humid environment and send it to Arizona and the two problems collide. Hello split backs and tops.

southcoastukes
08-03-2017, 04:17 PM
I think there is a lot of truth to the above. Who has the time to condition wood and cure it properly when you are building in the third world You have the wood then start making ukes. Proper seasoning takes time and in the sweat shops of Indonesia (and South east Asia), who has the time? Time is money. Personally I think building with "green" unseasoned wood is a bigger part of this problem than changes in humidity. That said, take an uke built out of green wood in a humid environment and send it to Arizona and the two problems collide. Hello split backs and tops.

Hey Red,

I'm going to get all bent out of shape by your use of the term "third world" (well, not really). But good builders are good builders no matter where they come from. I'd imagine Latin America is much better in that regard than Asia; the tradition is just so much longer. Longer than North America, for that matter, by a long shot.

Just this year, as an example, I had a rare oppoutunity to meet one of the top luthiers in Cuba and see his work. Incredible stuff and really inventive variations on standard froms. I know my tropical American woods well enough to know there are materials in Cuba no one knows about, and I saw a couple of them that day - gorgeous! But what he also told me is that the wood he uses was cut by his grandfather, and he cuts wood for his grandson. That's the way a guild used to work in Europe, and if you listen to the Latins (I'm sure there's no prejudice here) they'll tell you the Spanish can no longer build the "true" guitar (though what they mean by that is subject to interpretation).

But this is not to say "Latins Good - Asians Bad". This fellow below is from Indonesia and one of the world's foremost builders. Here's a video somewhat apropos of this thread in that it's a comparison of one of his steel string guitars with an American Taylor:


https://www.youtube.com/watch?v=SMNCkhrA2Ig

cyber3d
08-03-2017, 04:32 PM
My Romero Creations Tiny Tenor is made in Vietnam. One of the favored places for handmade higher end ukes. China seems to be on the downslide. It's the high end builder culture vs mass production that gets ya. I've gone through three Kalabrand ukes. Kinda regret all of them.