Setting bearing: was Component Downbearing Gauge

[David Love]

So this creates an effective multiplier for calculating height of a string
above the rear string rests at the point when the stretched string just
touches the front of the bridge.  For 1 degree, multiply the rear string
length in inches by .018; for 1.5 degrees, by .027; for 1/2 degree by .009;
etc..  The other challenge is deciding how much bearing one should have in
a given section.   This seems to depend on the amount of available crown
and the relative stiffness of the board.  What is the best way, I've often
wondered, to calculate the amount of deflection that is likely to occur on
a given board under so many pounds of downward pressure--we're talking
about new and old boards.  If you knew that, then it would be easier to
figure out the amount of bearing.  However, I've also heard several
perspectives on this, from the goal of achieving a deflection of 1/2 the
available crown, to flattening the board entirely.  I'd be interested to
hear comments on this. 

David Love
davidlovepianos@earthlink.net


> [Original Message]
> From: Ron Nossaman <RNossaman@cox.net>
> To: Pianotech <pianotech@ptg.org>
> Date: 7/4/2003 8:51:55 PM
> Subject: Re: Component Downbearing Gauge