Procedure for producing wooden throwing balls for playing nine pins or skittles

摘要

The procedure consists of 5 stages; the first stage involves scooping out four pieces of wood (2, 3, 4 & 5), to produce a flattened cone interior, identical in pairs and in parallel planes. In the second stage the 4 pieces of wood are stuck together, symmetrically and with their planes (2a & 2b, 3a & 3b, 4a & 4b and 5a & 5b) aligned. The third stage requires the assembly of two further pieces of wood (1 & 6), which are not hollowed out and which have a flattened cone shape externally. The fourth stage involves the assembly of the 2 final pieces (7 & 8) and the final stage is the shaping of the assembled pieces of wood to form the external spherical shape.