Moistureproofing shop - now stage box

[gordon stelter]

Nice explanation, Sarah, but I think a dehumidifier
dripping to the outside in a sealed box is the best
way to go. Speaking of which: how do Dampp Chaser bars
dry out piano parts, as increased heat in a closed box
such as piano case only allows more moisture to reside
in the air?
     Thump


     G



--- Sarah Fox <sarah@graphic-fusion.com> wrote:

> Hi Bob,
> 
> Dehumidifier bars *alone* won't do it, as the RH
> will rise in the booth as
> moisture comes out of the wood.  There has to be
> some way of transferring
> the moisture from the inside to the outside.  This
> can be achieved with some
> degree of ventillation in combination with the
> dehumidifier rods.  (In other
> words, don't have the chamber too air tight.) 
> Fresh, cool air will enter
> the chamber at some higher RH, and then it will be
> heated, driving down the
> RH.  The air will then absorb moisture, and the RH
> will rise.  But
> eventually, the warmer, moist air is vented to the
> outside (the way the
> moisture is transferred), and it is replaced by
> cooler moist air, which can
> be heated to lower the RH.  Put another way, cool
> air of a given RH has less
> total moisture than warm air of the same RH.  Makes
> sense???  If you use the
> heat approach, you'll find some very cheap and
> effective ceramic heaters at
> the hardware store (perhaps $15 for 1000W of heat). 
> There's no need to blow
> lots of money on dehumidifier rods, and the
> efficiency is exactly the same.
> 
> A noisier but more effective way to dehumidify is
> with a running
> compressor-type dehumidifier, which will condense
> the moisture out of the
> air and drain it to the outside.  I think you can
> get one of these things
> for around $150.  I don't know which of these two
> methods would be more
> energy efficient.
> 
> A third way to dehumidify would be with a dessicant
> in an *air-tight*
> chamber.  (This might be useful for pinblock
> material, but it gets somewhat
> impractical on a large scale.)  There's a
> product/company called Drierite,
> out of Xenia, OH.  You can find it on the web. You
> can buy the stuff fairly
> economically in 50 lb bags.  Drierite draws moisture
> out of the air and
> incorporates it into its crystal composition. 
> Depending on the variety you
> buy, the stuff can have an indicator that changes
> color when it has soaked
> up as much moisture as it is able.  It looks a bit
> like blue kitty litter
> and turns pink with moisture absorption.  If I
> remember correctly, it can
> absorb about 5 or 10% of its weight in water.  When
> the stuff is
> "exhausted," you can heat it in an oven to drive off
> the water, so that you
> can re-use it.
> 
> Peace,
> Sarah
> 
> _______________________________________________
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> https://www.moypiano.com/resources/#archives
> 



		
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