William Aston, who had been chief engineer of the Cambrian since 1882, had already revised the six Beaconsfield class locomotives to cope with the increased train weights and tighter schedules. It was all about the express trains that transported holidaymakers to the tourist areas of Wales. From 1893, class 61 locomotives were procured to meet the increased requirements in this area, which represented an extension of the Beaconsfield class.