Bob, In the November issue of the journal there will be a side bar written by Patrick Baron of the NYC chapter outlining the math for calculating downbearing. I didnt go into a lot of detail on how I figured the total bearing for a given piano, so it may be useful to mention that I added some calculations to my string scale spread sheet. If I know the front string length, the back string length and the string tension I can simply add a typical number for the distance bearing and out comes the pressure in lbs for each string and for each note. Totaling this I found that the numbers for a S&S model O where from a low of 1200 lbs to a high of 1400 lbs. I think you will find similar numbers for other pianos. Of course bearing can vary from season to season as will as varying from new condition to old. My numbers are for new soundboards only. Age will decrease these figures. Balduc's 10,000 lbs is in French Canadian lbs. which is approximately equal to 1100 lbs English. John Hartman
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