Changing roller size.

JIMRPT@AOL.COM JIMRPT@AOL.COM
Fri, 1 Sep 2000 11:51:06 EDT


In a message dated 9/01/2000 11:13:07 AM, you wrote:

<< Ok,  Here we go.  I would like to hear the relationship between 
knuckle size and backchecking defined. 
Thanks, 
Ed Foote>>

Troll!!?? Moi?
Well this is the first time I have ever been called a Troll. :-)

All other things being equal, (we know they ain't but humor me here) a 
smaller knuckle would  require a higher capstan to get the same hammer 
line,.... but since we only changed the roller/knuckle the key must move 
further to reach letoff and it is this addtional key travel that produces a  
higher catch point for the backcheck. Distance to let off/key movement ratio 
comes into play here.  The change in the roller/knuckle dimension is 
reflected in the distance the key must move. Ergo, egads and gadzooks! there 
is a realtionship between smaller/larger knuckles and backchecks......que?
  The same thing happens when you change heights of your capstans, i.e. 
hammerline, in that the backcheck catch height changes also.

 If I am totally screwed up here it won't be the first time Ed. :-)
Jim Bryant (FL)


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