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I have a commission about to be started to a gentleman in Singapore. He tells me he is a bit concerned since their RH is pretty much in the 80's and higher all year round...
For you guys that have done this or you that haven't but know how to proceed.... what should I do? I build at about 50% - 58% RH a bit higher or lower should be fine, but in the 80's constantly?

Thankspeterm39052.8859953704

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

no one shipping to Asia?

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

I guess all I can say is do not offer any warranties.

Really, I don't know if you could make any promises. If you do decide to
build something suited to high humidity, make sure that there is a huge
label stating so right inside the soundhole in case it is ever sold
elsewhere. you could keep the woods and instrument in a high humidity
cabinet throughout the building process, but would run the risk of
collapse or cracks if it is brought down to a reasonable humidity for any
length of time. I think it would be unreasonable to try to maintain 70% or
higher in your shop for any length of time.

Natural glues like hide glue would probably be poor choices, leaving PVAs
and epoxies as the most likely alternatives. Even then it's a high risk
instrument. If I were to accept such a commission at all I would make it
clear that I assumed no liability for any environmental damages. No
bridge or brace reglues, neck resets, neck twist or warp, top cracks, etc.,
would be warrantied. You could use as much graphite as possible where
appropriate, but even then I would consider this an environment better
suited for a Rainsong.David Collins39052.8992939815

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Eschew obfuscation, espouse elucidation.

Raise your shop humidity to about 70% or so. When you ship it put a couple of humidifiers in the case. It will live well at 80% without much change if you build it in a similar environment.

Ron

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OLD MAN formerly (and formally) known as:

Ron Wisdom

Somewhere in the middle of Arkansas......

[QUOTE=old man] Raise your shop humidity to about 70% or so. When you ship it put a couple of humidifiers in the case. It will live well at 80% without much change if you build it in a similar environment.

Ron[/QUOTE]

Ron, unfortunately the other guitars wouldn't be too crazy about that idea!

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Peter, how about using fish glue, supposedly, it keeps it's huge strength when exposed to humidity, Alain could tell ya more if he chimes in Al?

[QUOTE=Serge Poirier] Peter, how about using fish glue, supposedly, it keeps it's huge strength when exposed to humidity, Alain could tell ya more if he chimes in Al?[/QUOTE]

Hey Serge, I read the opposite, that fish glue was more liable to let go in high humidity:

Q: I was told that fish glue is just as good as hot hide glue, just as strong, and much easier to apply. What do you think about doing a player with it?

A: Fish glue is a "specialty glue" only. It is not designed to glue player actions together. It is mainly used for emulsions, but the pipe organ industry uses it to get an instant grip between leather and leather, or leather and cloth. It allows soft lambskin to be contoured around corners because of its cold tack properties. On the other hand, fish glue is very hygroscopic (meaning that it draws moisture from the air). Long-term humidity alone can disassemble parts put together with fish glue, whereas hot hide glue, once fully dry, can withstand about any amount of humidity without weakening, and over 400 degrees Fahrenheit without softening.

I read that
HERE

Peter, I have heard of builders making guitars to sent to the tropics in a build room at around 50%RH one precaution as I recall was to shellac the inside to slow the moisture transfer so no spikes occur. I cannot remember where I read it, but it is on the net somewhere

I do know that an RH that is too low is much worse than an RH that is too high, I would also imagine that the top and back radius would be better left a little flatter, say 18' for the back and 28 to 30' for the top.

I would spend some time at Frets.com, Frank is the king of this type of info, maybe he will tune in.

Cheers

Kim

Thanks for bringing that up Kim, i'll remember this! great input sir!

Sorry Pete!

Peter
Besides using a moisture resistant glue.
The wood you use can be a factor, redwood has less
movement with humidity changes, than spruce.
As an example: you build at 55%RH the guitar lives
at 75%RH The guitars Moisture content will increase
by about 4 1/2% This change in MC calculates to
Redwood swells to .048 wider and Sitka spruce .095 wider
Of course well seasoned wood will move less.
And yes less radius in the top and back could help also.
Just something I would consider.

Tom

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http://www.moriciguitar.com

Peter,
I live in florida. On the west coast. It is very hummid here most days (80-100%). I keep my shop around 50-55%RH. I think the ONLY thing you can do is tell the customer to slowly acclimate the guitar to the 80+ hummidity. Open the case let it sit for a few hours before removing the guitar and getting the full impact. I tell my customers that they need to be very cautious about the hummidity level and not expose the guitar to high hummidity/heat for too long of a time ( like going to the beach for hours). I also tell them I cannot warrant how the guitar will be affected if used in a high constant hummidity. The Action will/may be affected, as will the top, and perhaps as a result the tone. I can't control what happens to wood when exposed to extreme conditions. I also tell them to invest in a de-hummidifier...if they can afford the guitar how can they not afford to take care of it? There is no longer a warrantee as far as hummidity related issues go. As long as they understand that...we are all good.

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

That is going to be a tough one. Singapore is probably in the 80's when they have that 80% RH. That means the dew point is in the low 70's most days. That is the equivalent of 100% RH in your cozy 72 degree shop.

If you build a box to store it in when you are not working on it to keep it humid, watch out! Without ventilation mold will love you.

I'm sure you are right though. There must be a way to do it...

Good luck.

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Joe Beaver
Maker of Sawdust

See if Ameritage will make a custom case packed and padded with Tidy Cat
Crystals.

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Eschew obfuscation, espouse elucidation.

Really though, including an Ameritage case with thier humidity control
system would seem like a must, although I have no idea how much moisture
for how long thier system will handle. You can do your best, but in a
situation like that I would make it clear that the instrument will not come
with any warranty.

_________________
Eschew obfuscation, espouse elucidation.

Thanks for all the input.

But, how does Taylor and Martin do it? Amongst many other, they sell their guitars there too....

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

They will sell thier guitars to anyone, anywhere, and Taylor especially does
thier best to educate and encourage proper care. Then if something does go
wrong they will refuse warranty service on anything deemed to be
environmentally related.

_________________
Eschew obfuscation, espouse elucidation.

Peter,

One other consideration, even if it is wet and humid there, what envirorment will the guitar be in? Used in an air conditioned area? Stored in air conditioned room? Used outdoors? If it is kept in the case or only used for a limited time when outside it may not be that big of a problem. Just some food for thought.

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Joe Beaver
Maker of Sawdust

Peter, you'll mostly have setup issues I believe as the wood will try to grow and the guitar will swell up increasing you action. The good news is wood is about 10 times stronger in compression than tension so structually you should be fine.
If you have the luxury of raising you shop humidity it be a good idea but don't go crazy with it.
Jim_W39053.8703009259

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Jim Watts
http://jameswattsguitars.com

Thanks,
I think the best way is to make sure the customer keeps the guitar in the case with a de-humidifier and I'm sure it'll be fine.

Thanks for the help.

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Peter,

I think you will find that low RH is much more of a concern to Taylor, Martin and anyone else who builds guitars than high RH. There is some great old guitars all over the Northern Territory and North QLD, these regions regularly get to +100 degrees F with 100% RH and the axes are doing just fine.

HERE is a link to the TommyE site where his tech mentions this issue.

I would just build it Peter, maybe shellac the inside with a well diluted cut to moderate or buffer the extremes, shallow up the radius a little and instruct the client to keep a little silica in the case as suggested by TE's tech.

As described HERE you can get little bags that change colour as it becomes charged with moisture, when it turns pink you just bake it in the oven until it turns blue. Just be sure not to add too many bags or you will cause splitting due to the RH being too low.

Oh, and use HHG, it is the least affected by humidity and temp and won't creep like PVA and Co. Epoxy is overkill IMHO.

Cheers

Kimlarkim39053.8978240741