This is the method I prefer for a quick check of downbearing. It's a modified dial gauge and the three feet are 1 inch apart. When set on a level surface the needle points straight down to 6:00. Each increment on the gauge is .001". So when set over the bridge with the center foot centered on the bridge and the outer feet on the front and back scale, it gives a very quick reading of the total bearing (sine(1o) = .018. The photo shows about 1 degree of residual bearing. Of course, it's relatively useless for setting up bearing on an unstrung board but so is any other gauge. My latest foray is to use my ribscale spreadsheet for calculating the amount of total deflection under load and predetermine the bridge height based on calculations (I just hate cutting those stupid little slots and pulling strings around). I still use a string and a square to determine whether the bridgetop is square and canted properly front to back when I do the dry fitting. My final adjustments come from using an adjustable plate perimeter mounting system. David Love davidlovepianos at comcast.net www.davidlovepianos.com -------------- next part -------------- A non-text attachment was scrubbed... Name: P6140011.JPG Type: image/jpeg Size: 23934 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20060614/c3ff21a0/attachment-0002.jpe -------------- next part -------------- A non-text attachment was scrubbed... Name: P6140012.JPG Type: image/jpeg Size: 26954 bytes Desc: not available Url : https://www.moypiano.com/ptg/pianotech.php/attachments/20060614/c3ff21a0/attachment-0003.jpe
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