Steinway casters orientation

JIMRPT@aol.com JIMRPT@aol.com
Fri, 16 Jan 2004 13:33:30 EST


In a message dated 16/01/04 12:23:58 PM, 741662027@charter.net writes:

<< Notre Dame still stands with the

flying buttresses, eh?  Time to check assumptions:>>

Cy.......well if the legs have  "buttresses" they are the flared portion of 
the leg top which run fore and aft of the leg and not sideways.



<<2.  The caster pivots around a vertical axis that is coaligned with the

center of the leg.>>
And, in my opinion herin lies the problem. The typical S&S caster is offset 
from the center line by aprox 5/8 inches...or a total offset for both casters 
of aprox 1-1/4 inches. 
 Considering that the key bed will sag of its own accord, if laid across 
supports at the ends, doesn't it follow that two moments of movement aprox 1-1/4 
off center line at the end of 23 inch (aprox) 'unbuteressed' levers might be 
capable of causing some keybed movement?


<<As long as this is true, isn't what happens below irrelevant, as long as its

distance to the floor doesn't change?>>
 No, not in my opinion...besides the distance to the floor of the keybed will 
change depending on caster orientation......... 
  
<<Sure, there are two arms angling

downward that support the axle.  Are you saying that those arms sag under

the weight,>>
Absolutely, I have seen enough deformed S&S casters, as well as other makes, 
to support this in my mind.
 

<<so that if the casters are turned to face each other (caster

axles aligned fore and aft with the keys), then the ends of the legs splay

out away from each other? >>
Yep...see Conrads drawing. :-)

 Of course perhaps this thread has perhaps just a tinge of anal retentiveness 
embedded. ;-)


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