To whom it may confuse, I rebuilt a Baldwin SF last winter which was my first Accu-just system rebuild. To make life easier, I bought the Lowell downbearing gauge. Following Baldwin's procedure (Tech Sheet TS039D) everything went very smoothly. The piano sounded great. I remained smug and secure in the knowledge that I had this sucker under control until I had to reestablish the bearing on a seven year old 'L', under warranty, to try to improve tone quality in the octave six area. This is when I ran into the problem of translating the bubble graduations of the Lowell gauge into degrees. The bubble vial is graduated in groups of four marks. One would assume that each graduation was either a degree, or a quarter of a degree (15') with the bigger marks at every fourth being full degrees. Not so. Looking through both the documentation that came with the gauge, and the information from Baldwin, I found nothing telling me the graduation increment of the gauge in degrees! Are all the degree of deflection figures being passed about based on guess, or are they a mis-translation of the gauge readings? With these disturbing thoughts in mind, I went out in the shop to do what I have to do altogether too damned frequently in this business; get my own answers by empirical observation. I clamped the blade of my combination square (protractor head) in the bench vise and zeroed it so the foot was parallel with the blade. Then I placed the Lowell gauge on the foot and leveled it between two major graduations at one end. Then I rotated the foot of the square until the bubble centered between major graduations at the other end of the vial and read the resulting angle off the protractor. Guess what, four major graduations on the gauge equates to three degrees on the protractor. At sixteen minor divisions to three degrees, each minor division on the Lowell gauge represents .1875 degrees. That's 3/16 of a degree, or 11' 15". Each major division, therefore, would equal .75 degrees, or 3/4 of a degree, or 45' 0". There you have it, gang. That ought to give your grasp of reality a kick in the slats that will cascade back through all the measurements that you've associated with this gauge through the years. You're welcome, no charge. I would appreciate everyone with one of these gauges and a combination square with the protractor head to do this for themselves by way of verification. This is such a weird graduation increment, I'm wondering if they are all like this, or Tom's supply house snuck something strange in on him. In any case, why isn't this information in the tech sheet that comes with the gauge????????? Why haven't I seen it mentioned anywhere else?????????? Ron Nossaman
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