Zepher skin should not be used in rebuilding the Ampico "A"...Zepher skin, by its very nature shrinks and swells with any humidity changes, making it very difficult, or even impossible, to maintain the proper clearance between the pouch and the valve stem...Also, repeated humidity changes will eventually shrink the zepher skin until it causes the valves to stand open during dry weather..In addition, zepher skin is very attractive as food for insects... At any rate, to answer your original question...No, I know of nothing that is going to help the pouches, short of rebuilding them with the thinnest available leather you can find...The neatsfoot oil, and the spring treatment, will not forstall the inevitable...In order to get the maximum performance, and longevity from the restored instrument, the valve pouches really need to be rebuilt with thin leather..
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