 Prior to 1908, all four turntables had been 48' 5", which proved to be a problem as locomotives were steadily increasing in size.However, in that same year, the Redheugh Incline was closed, thereby allowing the track running alongside the southern wall of the shed to be lifted, and an extension built to accommodate three larger 60' 0" turntables .In the 1920s, the arrival of large 4-6-2 "pacific" type locomotives (the Vincent Raven designed NER "2400" class which became "A2" under the LNER, and the Doncaster built Gresley "A1s" designed for the GNR), necessitated converting the adjoining locomotive works' tender shop into a shed which could accommodate them, as even the 60' turntables in the main shed were not large enough.