Singing saws
Adam Cherubini, NJ
>Apparently there is something to the singing or ringing saw phenomenon. As I understand it, any metal will ring to some extent. But I'm told a hardened metal will ring differently.
Surface finish, including pits and rust will greatly effect sustain and ring quality, as will thickness and to a lesser extent hard and soft spots, or creases or dings. (In a previous post I guessed dings or hard spots, but failed to recognize the importance of surface finish).
Its not a great way to judge a saw, but it is a valid first step, not to be summarily dismissed. Here's what I understand, I don't know the physics behind any of this:
* A clean saw that doesn't ring may have a flaw you haven't noticed.
* A rusty saw that doesn't ring, may ring after a thorough cleaning.
* A saw that rings nicely with good sustain probably has a good surface finish, maybe uniform in thickness.
* A saw that sounds like another saw you like, may be similar in quality.
Adam
P.S. I've heard Todd discount the ringing anvil test. In case you are unfamiliar, some smiths say you should tap an anvil before buying. A good clear, sustained ring means the anvil is sound. A thud may mean the casting has a flaw or it has a hairline crack. I'm told the singing saw is a similar phenomenom.