Kerr, Stuart Information

Kerr, Stuart & Co. Ltd. began, as did so many of the Industrial locomotive companies, in Glasgow. Formed in 1881 as James Kerr & Company it was a dealer in railway plant, and actually sub-contracted orders for locomotives. The main supplier was Hartley, Arnoux & Fanning at Stoke-on-Trent, and in 1893 Kerr Stuart bought the company and became bona-fide locomotive builders.

As well as putting a lot of capital into the manufacturing plant, Kerr Stuart also developed a design philosophy that enabled them to produce locomotives to customers specifications built from standard parts. Looking through the catalogue you notice similarities in design and parts. Because the company ensured that stocks of these standard parts were always available, including completed boilers, it was possible to quickly complete a locomotive once gauge and other factors had been determined. Most of the smaller locomotives could be built in several gauges, the wheels being placed inside the frames for the narrower gauges, and outside for the wider gauges.

Another feature of their locomotives was that they were designed to be used where skilled labor and extensive maintenance facilities were scarce. Most contractors just bought a locomotive and expected it to run as long as water was in the boiler and fire in the grate. An occassional squirt from an oil can was what passed for maintenance. The Kerr Stuart locomotives were ideal for this type of environment as they were mechanically simple and robust, and "the works" were easily accessable. Early designs had outside Stephensons valve gear, while later designs in the smaller gauges had a "modified Hackworth" gear. Also, marine type ends were used on coupling and connecting rods.

The heading picture shows a WREN class locomotive. These could be built in any gauge from 1ft. 6in. to 3 ft. and was rated at 28 H.P. A total of 167 WREN class engines were built and shipped. The specifications were given in the catalogue as follows:

Cylinders			6in. diam x 9 in. stroke
Diameter of wheels		20 in.
Wheel Base			3 ft.
Boiler Tubes (Steel)		35 (1 3/4 in. diam.)
Working Pressure		140 lbs per sq. in.
Boiler Feed			Two Injectors
Firebox				Steel
Water tank (Saddle)		87 gallons
Fuel Space			5.5 cu. ft.
Heating Surface - Tubes		72.1 sq. ft.
Heating Surface - Firebox	13.9 sq. ft.
Heating Surface - Total		86.0 sq. ft.
Grate Area			2.19 sq. ft.
Approximate Weight, empty	3 tons 7 cwt
	in working order	4 tons 3 cwt
Tractive Effort			2,016 lbs

The next size up was the TATTOO class locomotive rated at 36 H.P. This could be built to any gauge between 2 ft and 4 ft. 8 1/2 in. A variant on this was the THAMES class that looks like a TATTOO but with side tanks rather than the saddle tank. Kerr Stuart built 80 of the TATTOO/THAMES class locomotive. The specifications for TATTOO were:

Cylinders			7in. diam x 12 in. stroke
Diameter of Coupled wheels	24 in.
Diameter of Bogie Wheels	16 1/2 in.
Wheel Base - Fixed		3 ft.
Wheel base - Total		7 ft. 6 in.
Boiler Tubes (Steel)		36 (1 3/4 in. diam.)
Working Pressure		160 lbs per sq. in.
Boiler Feed			One Pump and One Injector
Firebox				Steel
Water tank (Saddle)		140 gallons
Fuel Space			27.5 cu. ft.
Heating Surface - Tubes		89.5 sq. ft.
Heating Surface - Firebox	19.5 sq. ft.
Heating Surface - Total		109.0 sq. ft.
Grate Area			4 sq. ft.
Approximate Weight, empty	6 tons 10 cwt
	in working order	8 tons 10 cwt
Tractive Effort			3,485 lbs

The picture above shows a WREN class locomotive, PIXIE, used by the Devon County Council in a roadstone quarry, built in 1922 (works number 4260). It now operates on the Leighton Buzzard Narrow Gauge Railway. If anyone has any pictures I would love to get a couple to put up here. I would also like some ideas for liveries based on actual locomotives.

Just a couple of final thoughts. As I was reading about Kerr Stuart's policy of building several locomotives from standard parts, I could not help but notice a similarity to Maxitrak's method of providing several different kits, all based on standard components. Can't beat a winning method! I was also fascinated by the prices. You could buy a WREN for £450.00 and a TATTOO for £650.00 in 1932. A complete PEARL kit costs about seven times that amount now!