[TheForge] Re: Triangles

[Steve Smith]

Here's a tangled mess of messages from this spring. I've tried to 
organize them a bit; hopefully I haven't lost anything important, like 
the original author's name! I probably left out some good bits by accident.

Steve

=======================================
My data may be anecdotal, but it's pretty reliable.  Spring steel rings 
much better than mild steel, even when it's not tempered properly.  As 
an experiment, take a 12" piece of 1/2" round mild steel, bore a small 
hole in one end, run a light string through the hole, and hang it up. 
Do the same with a 12" piece of spring steel.  Strike them both.  Then 
try different pieces of spring steel tempered to different degrees of 
hardness.  If you do all this (I've done it -- just not all in one 
session), you'll definitely hear some differences -- and all of them the 
same shape.

Anecdotal
1 : relating to, characteristic of, or containing anecdotes <anecdotal
conversation>

Anecdote
1 plural anecdota, also anecdotes : items of unpublished or secret 
history or biography
2 plural anecdotes : a usually short narrative of an interesting, 
amusing, or curious incident often biographical and generally 
characterized by human interest

Mike Murphy

P.S.  I do get didactic and pedagogical, don't I?
=====================================================
The acoustic properties of steels are affected by many factors, and
"scientific proof", along with a lot of specific data is available if 
you know where to look. You might want to consider looking into a 
metallurgical reference book such as Metals Handbook or a text on 
ultrasonic inspection.

The two acoustic properties that come to mind as major players in
determining the sound of a triangle or bell are acoustic velocity
(longitudinal/compression, transverse/shear and surface)and acoustic
impedance. You can find this kind of data tabulated in metallurgical 
texts, and if you do a web search, I'm sure you could come up with a 
number of narrowly focused research papers on the subject. In any event, 
you'll find that carbon content, alloying elements, heat treatment and 
deformation/work (both cold and hot) all play significant roles. In each 
case, you'll find that the answer lies in how each of these factors 
affects the crystalline structure(s) of the metal. An FCC lattice can be 
expected to transmit sound differently from a BCC lattice or a highly 
strained martensitic structure, for example. Throw in the fact that most 
steels are a mixture of phases and the problem gets really complex. 
Acoustic impedance is probably the most complicated acoustic property of 
all. You're best bet is probably to research metallurgical texts for 
information on acoustic properties.

Dan
==============================================

I've used 3/8 inch round, 1/2 inch round and the same in rebar. I like 
to quench the angles after bending. The triangle has a better tone.

Mark
Snow Hill, Maryland

----- Original Message -----
From: "Michael H. Murphy" <blacksmith at comcast.net>
To: <theforge at mailman.qth.net>
Sent: Friday, April 30, 2004 9:55 PM
Subject: RE: [TheForge] Triangles



 >> I use half-inch round hot-rolled mild steel.  3/8 square does a good 
job, too.  I made one out of a spring, and it sounded real good, but
 >> straightening out a coil spring just wasn't worth it.
 >>
 >> Mike Murphy
 >>
 >> -----Original Message-----
 >> From: theforge-admin at mailman.qth.net
 >> On Behalf Of Woolley
 >> Sent: Friday, April 30, 2004 7:09 PM
 >> To: theforge at mailman.qth.net
 >> Subject: Re: [TheForge] Triangles
 >>
 >> What kind of steel do you use to make your triangles?
 >>
 >>
 >> Michael H. Murphy wrote:
 >>
 >
 >>> >I make one with four sides.  There is an eye punched in the corner
opposite to the open corner, which has a string through it to hang the 
four-sided triangle(I call 'em dinner bells) from.  Regular three-sided 
dinner bells should have the opening on one of the bottom corners.  I've 
tried it both ways, and it works better that way.
 >>> >
 >>> >Mike Murphy
 >>> >
 >>> >-----Original Message-----
 >>> >From: theforge-admin at mailman.qth.net
 >> [mailto:theforge-admin at mailman.qth.net]
 >>> >On Behalf Of Rich Maynard
 >>> >Sent: Thursday, April 29, 2004 5:41 PM
 >>> >To: theforge at mailman.qth.net
 >>> >Subject: RE: [TheForge] Triangles
 >>> >
 >>> >Good point. And with one being twice as long as the other, they 
should be an octave apart.
 >>> >
 >>> >Rich M.
 >>> >
 >>> >
 >>> >
 >>
 >>>> >>-----Original Message-----
 >>>> >>From: theforge-admin at mailman.qth.net
 >>>> >>[mailto:theforge-admin at mailman.qth.net]On Behalf Of Michael Horgan
 >>>> >>Sent: 29 April 2004 23:35
 >>>> >>To: theforge at mailman.qth.net
 >>>> >>Subject: Re: [TheForge] Triangles
 >>>> >>
 >>>> >>Usually down in a corner. This gives you two different lengths 
of steel ringing, making a pleasing chime tone. Try one both ways and 
listen, see what you think.
 >>>> >>
 >>>> >>At 12:12 PM 4/29/2004, you wrote:
 >>>> >>
 >>>> >>
 >>>
 >>>>> >>>Should the opening on a triangle that you ring be up next to 
the eye or down in one of the bottom corners?
 >>>>> >>>
 >>>>> >>>Keith "Sparky" Holmes
 >>>>> >>>
 >>>>> >>>
 >>>
 >>>> >>Michael D. Horgan , lughaid at earthlink.net
 >>>> >>http://members.aol.com/lughaid/
 >>>> >>posting from
 >>>> >>  A BRAZEN FORGERY
 >>>> >>Blacksmithing and Metalwork
 >>>> >>Claremont, Ca.