Susan Kline's comments on Verdigris are on target. Moisture accelerates the process. But the condition is caused by the placing of a brass CenterPin in a wool Bushing which contains Lanolin, a natural oil from the sheep. Both times that I spent working in a program for Techs at the Baldwin Factory at 1801 Gilbert Ave., Cincinnati, Ohio, I was educated to the fact that theytook great pains to wash the wool cloth in a chemical bath to get the oil out of the wool. I have observed over the years that these Centers were much more stable (because of shrinking the cloth) and did not develop the Verdigris problem. On the Verdigris problem itself, we worke many years ago with a chemist from duPont in trying to come up with a remedy. Two of the chemicals recommended at that time were a product called C.R.C., which dryed the moisture out of the cloth & Xylene, which dissolved the Verdigris. Neither were long-term solutions. We also completely took an Action & took all of the Centerpins out, reamed & hand-fitted and repinned with plated Pins every thing, and two years later, the vAction became sluggish. This stuff comes back to haunt you. Also, my wife helps do this work and she said we should not do this procedure anymore as it was so timeconsuming that we could "starve to death" better some other way. Over the teaching years we have always advised Technicians to try & sell new parts in the work & it would work out better over the long haul. We even took some Verdigrised wool out of a few Centers & tried scrubbing the Verdigris with a toothbrush & a chemical & the Verdigris had "eaten" into the Wool fibres to the point that the wool was not stable to repin. We have some good "blown-up " pictures of this that we have shown in the classroom trying to convince Techs to not waste time in repinning. Anyway, how can you hope to get the Pinning friction uniform if the wool Bushing is damaged.? Hope this can help. Willis Snyder
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