>>>So in your example of pulling a string up until it breaks and >>>seeing immediate indentation, this 'pinching' from the sidebearing is a >>>bigger contributor than the downbearing. >>> >>>Phil F >> >>Not to mention that if your string's designed to be at 150 lbs tension at >>60 percent breaking strength you would have to pull the string to 250 lbs >>(nominally - probably more) to break it. That runs the 5.4 lbs >>'pinching' figure up to 9.0 lbs and the downbearing figure from 2.7 lbs >>up to 4.5 lbs for a total of 13.5 lbs. That's getting up there. I'm not >>surprised that that would indent the cap. >>Phil F > >Me either, but then that's not nearly the PSI load the first increasing MC >cycle will put on the bridge, so the typical capping and pinning >configuration appears to be doomed to crushing the notch edge if it lives >where there are humidity swings. > >Ron N Agreed. Maybe the first test for your capping material should be to put on a few strings and pull them up until they break. If you see any significant cap indentation then it's back to the drawing board. Phil F
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