Bearing Setting was: floating plate thread

atonal@planet.eon.net atonal@planet.eon.net
Fri, 6 Jun 1997 20:30:52 +0000


> Richard;
> In a message dated 6/5/97 11:24:35 AM, remoody@easnetsd.com (Richard Moody )
> wrote:
> <<Which in their very excellent service manual  settings are given,
> but I don't remember specs for front bearing vs rear (back) bearings.>>
> 
>  Richard other than basic settings, i.e. 1/3 of hitch pin, I don't believe
> that they do give "specs", rather they speak of "adjusting" height to alter
> bearing. And in the catalog they offer a bearing gauge designed for use with
> the accujust pins ?
>  If I left the impression that there is a specific spec, it was not
> intentional.
> Jim Bryant (FL)


Gentlemen, 

	According to my dog-eared Baldwin Service Manual, bearing (measured 
from the front of the bridge) should be set approximately .005" in 
the top treble section, .007" to .010" in the mid treble & tenor 
sections, and between .010" and .030" in the bass section on 
Accu-Just instruments. These bearing settings are a guideline only, 
and not gospel. They also point out that adjusting the Accu-Just 
settings for whole sections of the piano will have a greater overall 
effect on the bearing for the section. Baldwin stresses that the 
Accu-Just system works best with minimal positive bearing, rather 
than loading up the bridges with lots of positive bearing (common 
sense dictates this).

	As for a factory tool, I asked the Baldwin factory techs what they 
use for bearing setting, and Tommy Edgeman (production supervisor) 
pulled out a familiar looking rocker gauge, with 'Baldwin' stamped on 
the side (available from Baldwin, along with a pamphlet on setting 
bearing  1-800-876-2976 ext 8585). They use this in combination with 
automotive feeler gauges to determine the amount of bearing present. 
I also use a dial gauge for quick and accurate bearing measurements. 
For adjusting the strings up & down on the Accu-Just pin, the factory 
guys recommended a blunt screwdriver for tapping the strings  down, 
and a coil lifter with leather or heavy felt padding under it for 
lifting the strings up. You must lower some tension to do this, and 
again, this will affect your final bearing measurements when the 
strings are pulled up to pitch. Horace said it when he mentioned you 
need lots and lots of time for  good bearing setting results.

	As a sidenote to the plate thread, I restrung a 1960 L (6'3") and 
the tail of the plate sprung up a full two inches from the 'double 
dowels' it was resting on when the bolts were removed! 

Happy Thursday, 
Rob Kiddell, 
Registered Piano Technician, PTG
atonal@planet.eon.net


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