Casgliadau Arlein

A mechanical rock drill for use on the quarry rock face (used to drill charge holes). This rock drill was manufactured by Ingersoll Rand, and is an early example of a rock drill. The rock drill is unusual in that it has a square shank – 99% of rock drills have a hexagon shank.

From the 18th century the introduction of blasting to remove blocks of slate from the rock face meant that quarrymen needed to drill charge holes in the rock. This was traditional done by using a hand held ‘jympar’. Hand drilling with a ‘jympar’ was a very slow process –it could take a man all day to drill a single 2 meter hole. The slowness of hand drilling meant that quarries looked for a mechanical alternative, and rock drills (or pneumatic drills) were adopted. Pneumatic drills were used at Pen yr Orsedd Quarry (Dyffryn Nantlle) from the 1880’s, however Penrhyn Quarry did not use them until 1912, and Dinorwig did not use them until 1919.