| Here's a letter to Acoustic Magazine, written by Earle White of the
ClimateCase Company, regarding maintaining proper humidity for your
guitars that I pulled off the internet.
I think it's a little extreme, but he has some good tips here:
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Article 40216 of alt.guitar:
From: [email protected] (Earle White)
Newsgroups: alt.guitar
Subject: Thermal/Humidity Protection
Date: 7 Mar 1995 06:02:13 GMT
Organization: Netcom
Lines: 164
Distribution: world
Since I've noticed numerous postings in this newsgroup concerning thermal
and humidity protection for stringed instruments, I'm taking the liberty of
posting the following letter I wrote on the subject to Acoustic Guitar
magazine. The letter should appear in the May/June '95 issue.
There seems to be lots of misunderstandings concerning thermal and humidity
control and protection. Hopefully, this letter will clear up the cloud factor,
just a little.
If you have any questions or comments, my contact info appears at the end of
this letter... Best Regards
=======================================================================
Editor,
Acoustic Guitar Magazine
PO Box 767,
San Anselmo, CA 94979-0767
Re: Letter for publication in next issue ...
Dear Sir:
I want to commend Acoustic Guitar and Bob Taylor for the technically
excellent article on how humidity affects guitars (September/October 1994).
Beyond the usual brief comments, such as "don't put it in your car" or
"humidify your instrument in the winter", it is very rare indeed to find any
definitive media coverage on the perils that routinely affect guitars and other
stringed instruments in the real world.
In fact, the leading cause of instrument damage and expensive repairs is
exposure to excessive temperature and humidity conditions. Just ask any repair
person about cracked and shattered finishes, top crack repairs, bridge reglues,
neck resets, and various other re-gluing, straightening, and restoration jobs.
He'll probably tell you that, aside from routine maintenance items like refret
jobs, as much as 90% of the repair business comes from thermal and humidity
abuse. Even the best hardshell case is inadequate protection when an instrument
is exposed to rapid changes and extremes of temperature and humidity.
Aside from use of synthetic materials, hard shell cases really haven't
changed much since the 1800's. Currently available hard shell cases themselves,
do not provide adequate thermal or humidity protection to accommodate routine
weather changes, much less the exposure that occurs when the instrument is
taken outside, or left in a closed automobile or aircraft cargo hold.
The reality is that stringed instruments made of various woods, plastics,
metals and other dissimilar materials are susceptible to damage from heat or
cold, and from excessive dryness or humidity, as evidenced by the
thermal/humidity damage present on the vast majority of used and vintage
instruments. No matter how much effort the luthier puts into obtaining
stabilized tonewoods, de-stressing instrument structures, or developing
elasticized finishes, a guitar will eventually show damage due to
thermal/humidity exposure unless it is kept in a stable environment. In
addition, world class high performance guitars are more susceptible to damage
than lesser instruments, due to lighter overall construction, thinner tops,
smaller braces, and closer tolerances.
Indeed, the finest close-tolerance high performance acoustic guitars of all
time are being made right now, by a host of highly-knowledgeable and talented
builders using modern tools, close tolerance CNC machining, and superior
quality standards. So, will these instruments survive in better shape than
their vintage counterparts? Is 1880's case technology going to do the job in
today's world?
PLAYER AWARENESS IS THE KEY. The answer is:
1.) Stabilize the guitar by buffering thermal and humidity changes;
2.) Use a lab quality (+/- 5% accuracy min.) thermometer/hygrometer in your
instrument case to accurately measure the instrument's environment;
3.) Humidify or dehumidify (as appropriate)using water-retentive clay-based
humidifiers or tyvec-packaged desiccant packs (respectively) in your instrument
case when warranted.
So, what about some guidelines? Our lab and real world research suggests:
If ambient humidity is 40% or less - humidify your guitar; if humidity is 70%
or greater - dehumidify. For safety's sake, strenuously avoid rapid temperature
changes (more than 20F per hour), and exposure to temperatures less than 45F or
more than 105F. Naturally, individual instruments respond differently to
thermal and humidity stress, some being more sensitive (i.e. more easily
damaged) than others. In turn, the above limits are meant as a guide only -
it's better to be safe than sorry. Also, it is a good idea to let your
instrument adapt slowly to significantly different conditions while inside its
case - before removing it!
If you have old guitars, bear in mind that they may be more susceptible to
damage due to the old type glues and finishes, and may also have compromised
glue joints due to repeated exposure and aging, hence, more care is indicated.
Luckily, most of these older-type glues and finishes were discontinued years
ago in favor of stronger, more durable, temperature/humidity-tolerant glues and
finishes.
By the way, I recommend water-retentive clay humidifiers since they maintain
a more constant humidity level than foam, and do not dry out as readily.
Tyvec-packaging of desiccant (aka: silica gel) more effectively prevents the
powdered material from escaping into your case and onto your guitar�s finish.
Desiccant is a silicon-based product roughly similar to glass; therefore, it's
definitely something you don't want to breathe or polish into your guitar's
lacquer finish.
Buffering your instrument from thermal/humidity changes can be a difficult
problem. Wrapping blankets or other insulation around the instrument has been
done for years, and really does no good since it isn't airtight. Sleeping bags
have been used, and do provide some degree of marginal protection --
approximately 2-3 times that of the case itself, depending on the bag rating
(polar-rated is better). This approach is certainly better than nothing, but is
inconvenient and can be dangerously ineffective. After about 12 years of
experimentation, I designed a simple, effective, and inexpensive solution to
the problem, namely the ClimateCase case cover.
The ClimateCase cover is designed to stabilize wooden instruments, by
providing a ported, nearly air/water-tight, and insulated buffer between the
instrument and the external environment. It reflects about 90% of heat and
sunlight in hot conditions, compared to black hardshell cases that absorb 90%
of heat/sunlight. Due to a thermos-bottle type effect, it also retains about
90% of warmth in cold conditions. Overall, it provides over 10 times more
thermal protection than a black hardshell case and, because it's nearly
air/water-tight, it stabilizes the humidity level inside the instrument case.
Of course, it also protects the instrument case from wear and tear, dust, and
rain.
We have done considerable engineering research into the causes and effects
of thermal and humidity exposure on musical instruments over the past 16 years,
and would be happy to answer any questions your readers may have on these
subjects.
Thanks and Best Regards,
Earle White (ClimateCase Co.)
POB 506, Grass Valley, CA 95945
(916) 272-3603
Internet Address: [email protected]
===================================================================
NOTES: The best known clay-based humidifier is the "Guardfather", which when
used with a ClimateCase will retain 50% +/-5% in fairly extreme conditions
(down to ~20% ambient RH). Guardfather humidifiers only cost about $2.00 from
Elderly Instruments in Lansing, MI (517) 372-7890. FAX is (517) 372-5155. They
also have about the lowest prices on the ClimateCase thermal/humidity
protective covers also. Tyvec or MIL-std packaged desiccant can be obtained
from ADCOA (manufacturer), or one of its dealers. ADCOA's phone number is
1-800-228-4124.
IMPORTANT!!! MAKE SURE that you use a LAB-QUALITY humidity guage, preferably
solid state. Note that most small humidity guages have accuracies of +/-20%,
which is dangerously imprecise. Other types may be designed for weather
forecasting use, and may be mechanically undesirable since an instrument case
can see fairly rough action (shocks) every now and then. This type will not
maintain accuracy if it is knocked around. Additionally, most humidity guages
supplied with currently available humidifiers are accurate to +/20 to 30% only
(and don't ask me why they supply such junk!) I guess, the cliche "ya gets
what ya pays fowr" applies here too.
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