>Perhaps the heavy use kept the metal malleable? > >Terry Farrell And what about the next one that was also heavily used and cracked up badly? No, I don't think so. Also, all of these speculations about how use affects work hardening and how that causes the cracking don't fit field observations. We don't know the composition or condition of the brass when the rail was originally installed. Was it annealed? Was it already work hardened? Was it already cracked? What was milled and drilled, and what was stamped? Will annealing a rail that's not yet cracked keep it from cracking? Not knowing what was there originally, it just isn't possible, much less reasonable, to speculate on whether or not heavy use (or lack thereof), or whether it was annealed before installation had anything at all to do with what cracked and what didn't. There's just no information to work with. Those rails might very well last another 80 years with no problem. Or they might not. This is no different than deciding whether to replace that pinblock,or go with oversized pins - or lower the plate to get string bearing without worrying too much about soundboard crown, or keep the old wippens because they don't look that bad, or any other of the hundreds of decisions we make about what is likely to be adequate and what possibly may not be. Given the option, I'd prefer to replace the rails. Ron N
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