Shanks had started his own machine making and spinning firm at Ogilvy Place, Arbroath in 1825. His invention was horse drawn and unlike it competitors rolled grass as it cut, creating the all-important smooth lawn. His grass cutting machine as it is described in the original patent document had long low lines, rear guiding handles and a horse towing bar projecting from the front, in appearance similar to an iron plough. with roller, cogs and cutting blades in place of the sock and coulter.

Alexander Shanks needed help in promoting his new machine and turned for advice to William F. Lindsay Carnegie of Boysack, a local landowner interested in new ideas. Carnegie immediately saw the possibilities of Shank’s (horse-drawn grass cutting machine), and ordered one for his estate at Kinblethmont. The first trial of the new cutting machine took place in 1842.

As gardens and gardening gained in popularity with the middle classes, Shanks along with other lawnmower manufacturers began to produce more and better models to cater for this growing market. The firm moved into bigger premises in Arbroath at Dens Iron Works. They opened a showroom and office in London supplying lawnmowers as far south as the Isle of Wight, and diversified into other aspects of ironwork. It seemed that the ‘Grassie’ as the Dens iron Works was affectionately known would continue forever, but in the 1950s the manufacture of lawnmowers in Arbroath was taken over by a Birmingham firm, and in 1969 an era came to an end.