Covertcoat was built in 1898 for shunting at Port Dinorwic as well as for use at Dinorwic Quarry. This locomotive was originally named "The Second"; it was later re-named in 1913 as 'Covertcoat' after the horse owned by Sir Charles Asheton Smith that won the Grand National in 1913. Sir Charles' family were the owners of Dinorwic Quarry - they typically named their new loco's after their horses.

Covertcoat spent most of her working life at Port Dinorwic until 1925 when she was sent up to the 'Californian' level in the quarry. She fell out of use in October 1959 and was later sold in 1964 to John Butler of Ripley in Surrey who preserved the locomotive; Covertcoat was later purchased by Launceston Steam Railway in 1984.

Covertcoat's cab was re-designed to be of an open back design, an unusual take on the traditional Hunslet look. A tender was constructed in 1991 to provide a larger volume of water and coal to be carried.

​

Her firebox is not original, rather 20% larger than the one she had previously carried to allow for a bigger fire; therefore reducing the time it took to build pressure. This was built over the winter of 2005/6 along with a new boiler.