[TheForge] Re: triangle bells/rebar

[Peter Fels And Phoebe Palmer]

Mike:
Dust it with any very fine powder and ring. Where the powder remains are 
the null points from which to hang it...PF

Mike Spencer wrote:

>Andy g. quoth:
>
>  
>
>>>The stuff you learn early on holds a disproportionate place in your
>>>memory.  I never trusted rebar after that.  Even if it *does* hold up
>>>bridges, overpasses and aqueducts.
>>>      
>>>
>>Works great when surrounded by about a ton of concrete.
>>Then you don't have to look at it, either.
>>    
>>
>
>*SPLORF!*
>
>Now that I've picked myself up off the floor, sopped  up the spilled
>coffee and wiped the monitor......
>
>It occured to me that there are several other things to which that
>would apply quite satisfactorily.  And maybe a couple of people, too.
>
>
>Back on topic:  I have some brass tube -- leftover stock, I was told,
>from a WW II contract at Acadia Gas Engine for bombsight parts -- that
>rings melodiously when tossed into the air and struck.  But when I try
>to hang a piece to make a chime, it varies between rather dull and
>dead as lead except when hung on fine monofilament.  Which isn't too
>useful because the monofilament chafes through real quick.  Tried
>numerous cute little metal pins and widgets, nylon twine, leather.
>
>But I have a vague recollection from high school physics that tubes
>have weird vibration modes and harmonics.  Maybe I have to know
>exactly where the nodal point(s) of the vibration are.
>
>Say, maybe you could analyze the triangle gongs to determine where the
>least-vibrating nodal point(s) is(are).  Um, lessee: magnetize one
>just enough so that iron powder just barely kinda sorta sticks to
>it. Very light coat of white paint.  Iron powder all over.  Ring it
>and see where the iron powder falls off.  Those place are vibrating,
>aren't nodes and shouldn't be used to suspend it.  Or something like
>that... 
>
>- Mike
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>