[Bell Historians] Clappers

[David Bagley]

Matthew's right, the flight is very important.

I also think I'ts due to nodes and anti nodes of vibration along the length 
of a clapper. The material, as we all know, is very important. How many 
times have we heard about the differences between wrought iron and SG?

The clapper pivot needs to be at a node (null) otherwise it will put the 
staple under too much force and break it, which when it was a small piece of 
wrought iron cast into the bell was important.

The mass of the ball means that it is unlikely to vibrate much when struck, 
so this too should be considered as a node.

The flight therefore could be considered to "tune" the clapper such that the 
pivot is as close to an node as possible.

I can imagine blacksmiths of old reshaping the flight in the forge until 
they felt minimim shock at the pivot when hitting the other end.

Only wrought iron can be "tuned" in the forge. SG shafts can be turned down 
on a lathe, but has anybody ever thought of "tuning" them for a node at the 
pivot?

David




----- Original Message ----- 
From: <matthewhigby at ltekOZbFba30-cScjUn8A3_DmxpRSmInXEy4x254U2MiN7Q0BW8KWmr0pVKVC8oRnP_fyc-iCo1uwfijP64.yahoo.invalid>
To: <bellhistorians at yahoogroups.com>
Sent: Friday, July 30, 2010 11:33 PM
Subject: Re: [Bell Historians] Clappers



The flight has various functions. Briefly I will try and describe them!

Firstly - have you ever played Cricket? Try hitting the ball with the top or 
bottom of the bat - the ball doesn't go too far and it hurts your wrists. If 
you hit it with the middle of the bat (optimum strike point) the ball goes a 
long way, without hurting. The same principal works with a clapper.

1) The flight reduces stress on the clapper pivot.
2) The flight balances the clapper, to give an optimum strike point (similar 
weight either side of the ball).
3) The flight makes the clapper into a longer pendulum, gives more wind 
resistance etc, to slow the clapper down. Clappers with short flights swing 
quicker, making the the bell harder to get up with the clapper "right side" 
(particularly when combined with a heavy headstock).

Hope this helps,

Matthew


What is the purpose of the flite (or is it flight) on a clapper? Does it 
have an aerodynamic function or is it a vestige of  former use as the point 
at which to attach a rope for chiming ?
Peter Trent







-----Original Message-----
From: Peter Trent <peter.trent at OsrRHG84C_Ik4EQHsABMuXfpMHenw72dBlOt1buz5hl9YPMdvKtuOsTKeKGSy3VKmsGGhHIJA6aOo_FDxAWOFA.yahoo.invalid>
To: bellhistorians at yahoogroups.com
Sent: Fri, Jul 30, 2010 11:00 pm
Subject: [Bell Historians] Clappers





What is the purpose of the flite (or is it flight) on a clapper? Does it 
have an aerodynamic function or is it a vestige of  former use as the point 
at which to attach a rope for chiming ?
Peter Trent