[pianotech] Downbearing

[Ron Nossaman]

> I can think of one argument for zero back bearing, but I make no claims 
> as to its practicality. It involves the same rationale as using vertical 
> hitch pins to facilitate bridge movement. It seems to me that zero back 
> bearing will minimize the tie down effect of the back scale length of 
> the string. It can best be pictured by thinking in extremes. Imagine 
> radical bridge deflection, i.e., the bridge wants to move +/- 10mm from 
> rest.  If your backscale bearing angle is a very steep 30 degrees (think 
> exreme) it will allow the downward movement but not much upper. Whereas 
> a zero back bearing angle will minimize the hampering of the movement 
> and it will be more equal in both directions.
> 
> Dean

Well, no. It's the net bearing that will limit bridge movement 
if it is extreme, not the back bearing, and the net bearing in 
real piano angular deflection ranges would be functionally 
unaffected by zero back angle. I don't see any relationship to 
vertical hitches here either.???
Ron N