These instructions describe the construction of a model based on the original, designated H3, started in 1740 and took the originator, John Harrison, nearly nineteen years to build and adjust. He found that he just could not persuade the two large, heavy, circular balances to keep time well enough. Nevertheless, H3 incorporates two extremely important inventions both relevant today: the bimetallic strip (still in use worldwide in thermostats of all kinds) and the caged roller bearing, a device found in almost every modern machine
A 24 pages booklet describes the construction with technical data and parts list. A second 16 page booklet contains Isometric drawings and a separate sheet has reproductions of clock faces to cut out.
Please note these Model Plans are designed by individual Meccano modellers and may use parts not currently available. The level of instruction detail is dependent on the original modeller and varies from plan to plan. These are instructions only.