28-06-2023, 10:12 AM
Owen Springs of Rotherham confirm Duncan's theory that they are there to aid the lubrication and sliding in a dry spring. They also advise springs be dry as mention by Ruairidh, lubricant being able to pick up road dirt adding to wear. One would expect the zinc to wear after around after a ninety years or so but many appear as fitted. Perhaps the zinc is a low wearing alloy perfected by the spring manufacturer?