GWR 645 and 1501 Classes
class of 108 British 0-6-0ST locomotives
The GWR 645 and 1501 Classes were two closely related classes of 0-6-0ST designed by George Armstrong and built at the Wolverhampton railway works of the Great Western Railway (GWR). Thirty-six, the 645 Class, were constructed between 1872-3, of which three were built for the South Wales Mineral Railway (SWMR), two for the Carmarthen and Cardigan Railway (C&CR) and the remainder for the GWR. In essence, they were saddle tank versions of his GWR 633 Class of 1871. From 1878, a further 72, the 1501 Class, partially enlarged, were added. Unlike the originals, these had full-length saddle tanks from the start.
Construction
The whole class was delivered in nine lots, as follows:
645-655, plus one (Lot O, 1872)
656, 757-763, plus four (Lot P, 1872-3)
764-775 (Lot Q, 1873)
1501-1512 (Lot A2, 1878)
1513-1524 (Lot B2, 1878-9)
1525-1536 (Lot D2, 1879)
1537-1548 (Lot E2, 1879–80)
1549-60 (Lot F2, 1880)
1801-1812 (Lot G2, 1881)
Three of the un-numbered engines plus No. 767 were sold to the SWMR, and the other two plus No. 655 to the C&CR. The latter three returned to the GWR in 1881, becoming Nos. 902-904.
Dimensions
When built, they had 4 ft 6 in (1.372 m) driving wheels (later 4 ft 7+1⁄2 in or 1.410 m due to thicker tyres). The principal visual differences between the two classes were that the 645 class had short tanks and no cabs, whereas the 1501 class had cabs and full-length tanks.
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