Ron It's an old idea, and works very well if you don't need front and rear bearing information. For setting up new boards, no problem, but I've seen field diagnosis instances where pianos had negative front bearing and positive net, and clanged on the bridge pins on a hard blow. A rocker gage didn't indicate any problem, but the bubble gage showed it clearly. I see your point. Perhaps this gauge then has it's most useful in situation where there is still measurable positive bearing as long as the front termination is the highest point in the bearing line. Or perhaps a gap wouould appear under the front foot between the string & the bottom of the foot indicating negative bearing here. I'll have to experiement. I did start out using it as a verification gauge for bearing on new boards. In the scenario you describe then it would appear that this would not give enough information. Isn't the condition you describe kind of rare though? Usually old board are just negative period. Nevertheless I can see that the bubble gauge has an advantage in this situation. I've observed in many old boards it's really kind of difficult to tell what bearing exists even with the bubble gauge, not only because of a sunken board but the angle of the bridge top. IMO so much disinformation given using the Lowell gauge which is either operator error or just limitations of the device itself as to question it's usefulness in certain circumstances. I was hoping for something more reliable & simple. I do have a question though. I use the above formula to set up initial plate height with a thread, and my deflection calculations, but how do you use the sticks to set bearing before you have strings on? I haven't used the sticks to do this nor am I sure it can be done. I've always utilized a version of pre-stressing the board before I cut my bridge height & this has worked very well so far. I think that this type of gauge may give very useful & accurrate residual bearing information on newly set boards or on fairly new piano , on which we assume there is crown & bearing. Thanks for the feedback Dale Ron N -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20060611/b817de5b/attachment.html
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