[Bell Historians] A Short handstroke

[Andrew Aspland]

I suppose one could calculate it from a bell with single pulley – the pulley mouth is in line vertically with the sole of the wheel and is usually dropped by about 4” below the horizontal line (though this degree of dropping may depend on size of bell and bell hangers’ preferences).  For a 66” diameter wheel, by Pythagoras 33^2 + 37^2 = 2458,   2458^0.5=49.6,  49.6-33 = 16.6”  So 16.5” is shortest distance from wheel to pulley mouth.  The more a double pulley draws inwards the more it needs to drop downwards to maintain this distance.
Yours
Andrew

From: Peter Trent 
Sent: Wednesday, May 11, 2011 9:09 AM
To: bellhistorians at yahoogroups.com 
Subject: Re: [Bell Historians] A Short handstroke

  
 

Is there a rule of thumb or optimum distance between pulley mouth and wheel?
PJT
  ----- Original Message ----- 
  From: Andrew Aspland 
  To: bellhistorians at yahoogroups.com 
  Sent: Wednesday, May 11, 2011 8:45 AM
  Subject: Re: [Bell Historians] A Short handstroke

    

  For a practical solution on a bell already up and running (i.e. not possible in the bell hanger’s workshop):
  Measure the height of the sally off the ground when the bell is down, raise the bell and whilst holding it on the balance get an accomplice to measure the height of the sally again.  Calculate the difference between these two measurements and half it.  This is the distance the garter hole needs to move.  If the sally goes up when the bell is raised then the garter hole needs to go up.
  I believe some bells with double pulleys have been over compensated for – i.e. the grater hole has been dropped too much when initially installed.
  A less considered problem is the distance of the mouth of the pulley from the wheel: too close and the rope kicks and jerks as it changes from backstroke to handstroke, too far away and the whole thing is rather languid and  perhaps there is more danger of the rope slipping wheel.
  Before the augmentation the fifth (?) at Cookham had the pulley brackets mounted upside down so the pulley was really close to the wheel – very odd handling!
  Andrew

  From: matthewhigby at Q_nLwdkhp-jMC5DkSvB4Y_DafMV3rwWejjg9EWIYB--BcoWqAYKhlgkUn9jkSz7RsykRzKMYfWSSmg.yahoo.invalid 
  Sent: Friday, May 06, 2011 1:50 PM
  To: bellhistorians at yahoogroups.com 
  Subject: Re: [Bell Historians] A Short handstroke

    
  Basically the sally should be the same height when the bell is vertically up or down. Lay a plumb line over the gudgeon and pulley. Mark where it passes the wheel shroud. Measure the circumference of the wheel by laying a tape around the sole of the wheel then divide that by 4. Measure up from your mark by that amount and that should be your garter hole position (again lay year tape in the groove of the wheel, around the sole. The garter hole should then be the same distance from the pulley when the bell is vertically up or down. The sally being a little higher when set. Hope this helps. Matthew 

  Sent using BlackBerry® from Orange


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  From: David Willis <dcwillispiano at eCAKQDgjLjFmnn_YAqDWVJJyg-4dM_yZhl0GpGMmDycP_N4CJpCKMHYBmvwzFDq60Oi1GBOQcaXk3PF8Jqb09A.yahoo.invalid> 
  Sender: bellhistorians at yahoogroups.com 
  Date: Fri, 6 May 2011 13:25:31 +0100 (BST)
  To: BellHistorians<bellhistorians at yahoogroups.com>
  ReplyTo: bellhistorians at yahoogroups.com 
  Subject: [Bell Historians] A Short handstroke

    
        A bell in our group is suspected of having a short handstroke . My thought is that this is something that can be measured with the bell down ( of course ).

        If a line is taken from the garter hole to the gudgeon and another from the gudgeon to the pulley an angle is formed between the two . Too little resulting in a short handstroke . 

        Am I correct please and if so what is accepted to be the correct angle ?

        David
       


           
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