Re: [Harp-L] cleaning custom harps




----- 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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