When the wheels start turning at Hayes Engineering Works in Oturehua, watch out for fingers and toes.
The early 19th-century factory at the former home of Ernest and Hannah Hayes was the birthplace of a raft of inventions.
Useful tools for everyday farm use were developed at their 60ha property from the 1880s until the 1950s.
Curator Ken Gillespie has been showing visitors the workings of the historic workshop for more than 20 years.
Ernest Hayes was an innovative inventor, developing windmills, bait cutters and even a type of early snow chain.
One of his most recognised products was his refinement of J. Reid’s fencing wire strainer in 1924, which is still in use around the world.
The product was so good it received a design award decades later in the 1980s, Mr Gillespie said.
On operating days Mr Gillespie starts up the workshop to show how a complex array of wheels, belts and pulleys powered drills, saws, lathes and more.
Hannah Hayes was also an innovator, becoming one of New Zealand’s first travelling saleswomen, cycling to the faroff reaches of Central Otago to sell their farm implements.
The historic site held more than 3500 wooden patterns that were used to create the component parts of a wide range of tools.
The patterns were sent to foundries in Dunedin for casting, where patterns were placed in sand to create a mould.
The patterns were then removed, and the mould cavity was filled with molten metal.
After the company moved to Christchurch in 1952, Ernest’s grandson, Clive Hayes, and his brother-in-law, Doug Smith, remained in Oturehua and kept the workshop operational, albeit for maintenance rather than manufacture.
The engineering works were purchased by the New Zealand Historic Places Trust in 1975.
The site has remained largely unchanged, offering insight into early 20th-century production, and is now run by Heritage New Zealand.
Development of the Otago Central Rail Trail has seen the historic site become a popular stop along the trail, allowing for the development of a cafe on the site as well as Heritage New Zealand being able to continue to put resources back into the site to restore it, Mr Gillespie said.