Re: [Harp-L] cleaning custom harps

["Vern Smith" <jevern@xxxxxxx>]

----- Original Message ----- 
From: "Tim Moyer" <wmharps@xxxxxxxxxxxxxxxxxxxx>
To: <harp-l@xxxxxxxxxx>
Sent: Saturday, December 18, 2004 11:15 AM
Subject: Re: [Harp-L] cleaning custom harps


> To change the temper of brass you would have to heat it to red hot
> and then either quench it in cold water or let it cool gradually to
> room temperature.  Since boiling it in water would only subject it
> to a temperature around 212 degrees F (the boiling point of water),
> it shouldn't affect the hardness of the metal.

Although you are correct that the temperature of boiling water isn't high 
enough to affect the properties of reeds, they could be affected at 
temperatures above 200C or about 400F...much less than red heat.

The metal of reeds is generally hardened by cold-working (cold rolling) to 
break down the large grains.  Substantial annealing or re-forming of large 
crystals occurs in brass around 300C or 575F.    Quenching hardens ferrous 
alloys (e.g. high-carbon steel) by cooling the metal before carbon can come 
out of solution. Quenching will not harden brass which has no dissolved 
carbon.

Vern

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