Seller: blueclockmaker (1.284) 100%, Location: Gosport, Ships to: EuropeanUnion, Item: 382623886099 Centre Arbours for fusee clocks. Arbors and pinions We use EN8DM (BS970: 212A42) Medium Carbon Free cutting Steel for our arbours and pinions. We find this material, in its normal state, is hard enough for pinion work. However, the carbon content is controlled within the range that is suitable for components requiring flame or induction hardening.Standard range is .55 to .95 modules in 6, 7 and 8-leaf.For verge & high quality clocks ? we can cut silver steel pinions. Ask for details.