The Ivatt Q1, Q2, and Q3 0-8-0 'Long Tom' Locomotives
In the 19th Century, the Great Northern Railway (GNR) had tried
grouping the coal traffic between Peterborough and London into 50-wagon trains, but these were not successful
due to the lack of refuge sidings and the difficult of shunting these heavy trains.
By 1900, shunting locomotives had become more powerful and refuge sidings were generally longer, so
Ivatt design his GNR Class K1 (LNER Class Q1 and Q2)
0-8-0 to haul heavy 60-wagon coal trains along this route.
These used a boiler based on the C2 4-4-2 'Klondyke'
boiler but with a shallower dustpan. It also incorporated slide valves and 19.75in cylinders. The cylinder diameter changed
during the building of the first locomotives, but by 1913 they were all recorded as 20in diameter.
Due to their prominent long boilers, the GNR Class K1s quickly acquired the nickname of "Long-tom".
A total of 55 locomotives in seven batches were built between 1901 and 1909.
In 1908, No. 417 was rebuilt with a Schmidt superheater and with piston valves. Five of the last batch of ten locomotives
were built in this form. Over time, most of the original saturated boilers would be replaced with superheaters.
The last conversion occurred in 1920, leaving eight locomotives which would remain saturated for the rest of their
lives.
During the 1920s, most of the Schmidt superheaters would be replaced by the LNER-standard Robinson superheaters.
Eventually fourteen locomotives would be fitted with piston valves, and all of these had superheated boilers.
At Grouping, the slide valve locomotives (saturated and superheated boilers) were classified as Q1, whilst the
piston valve locomotives (all superheated boilers) were classified as Q2.
In 1913, Gresley fitted his 'Doncaster'
superheater design to No. 445. The Doncaster superheater attempted to improve on the Schmidt and Robinson types
by having separate headers for the saturated and superheated chambers, and
had already been fitted to the
J6 0-6-0 class.
No. 445 would be the only "Long Tom" to be fitted with the Doncaster superheater.
In 1914, Gresley rebuilt No. 420 with a 5ft 6in
boiler of the type used on his new K2 2-6-0.
The original plan was to fit his Doncaster straight-tube superheater (as with No. 445), but a Robinson superheater
would be fitted instead. An order was placed to convert ten more of the 'Long Toms', but this was cancelled and the
new boilers were fitted to the new K2 2-6-0s.
No. 445 remained the only locomotive with this boiler, and was given the LNER classification of Q3.
The "Long Toms" were built to haul coal from the coal fields in Nottinghamshire, Derbyshire, and South Yorkshire to
London, and they did this successfully for most of their lives. Previously,
J3 and J4 0-6-0 locomotives had been struggling with the rapidly
increasing coal loads; so the new 0-8-0s were very welcome. Locomotives were initially allocated to Doncaster,
Colwick, and Peterborough.
In 1917, ten "Long Toms" were loaned to the North Eastern Railway (NER) to replace their own
Q5s which had been moved to France. These were returned by 1920.
In the meantime, a new line had opened between
Langley Junction and Cuffley which took much of the Q1/Q2 traffic off the mainline. Also they began to be
replaced by Gresley 2-8-0s
(O1s and
O2s). As these new 2-8-0s arrived, the Q1s and Q2s
tended to move north to the Nottingham and West Riding areas.
By the early 1920s, the "Long Toms" were allocated to Peterborough, Colwick, and Ardsley.
As well as pulling their traditional coal trains, during the 1920s the "Long Toms" operated a number of other
services. Some of the Ardsley engines operated night goods services to Hull. They had a reputation of
having thirsty requirements on these services and acquired the local name of "Sea Pigs".
The "Long Toms" also became associated with the
evening "Keighley Wringer" service from Keighley to Wrenthorpe yard, which acquired its name due to the
carriage of the large numbers of household wringing machines manufactured in Keighley.
Withdrawals started in 1926, with priority being given to the locomotives with saturated boilers. All of the saturated
boiler locomotives had been scrapped by 1931, with the remaining Q1s and Q2s becoming extinct in 1935.
The Q3 was scrapped in 1937. The West Riding "Long Toms" (including the Q3) were replaced by
Q4s which could fit on Ardsley's turntable - unlike the new
2-8-0s.
Technical Details
The following details for Class Q1 are for the superheated version. Only seven members of the Q1 class remained saturated
during LNER ownership.
|
|
Q1 |
Q2 |
Q3 |
| Cylinders (x2): |
(inside) |
20x26in. |
21x26in. |
21x26in. |
| Motion: |
Stephenson |
slide valves |
8" piston valves |
8.75" piston valves |
| Boiler: |
Max. Diameter: |
4ft 8in |
4ft 8in |
5ft 6in |
|
Pressure: |
170psi |
170psi |
170psi |
|
Diagram No.: |
4 |
4 |
3 |
| Heating Surface: |
Total: |
1370.75 sq.ft. |
1370.75 sq.ft. |
1934.5 sq.ft. |
|
Firebox: |
135.5 sq.ft. |
135.5 sq.ft. |
152.0 sq.ft. |
|
Tubes: |
660.25 sq.ft. (97x 2in) |
660.25 sq.ft. (97x 2in) |
1082.0 sq.ft. (197x 1.75in) |
|
Flues: |
321.0 sq.ft. (18x 5.25in) |
321.0 sq.ft. (18x 5.25in) |
395.5 sq.ft. (24x 5.25in) |
|
Superheater: |
254.0 sq.ft. |
254.0 sq.ft. |
305.0 sq.ft. |
| Grate Area: |
|
24.5 sq.ft. |
24.5 sq.ft. |
24 sq.ft. |
| Wheels: |
Coupled: |
4ft 8in |
4ft 8in |
4ft 8in |
| Tractive Effort: |
(@ 85% boiler pressure) |
26,835lb |
29,580lb |
29,580lb |
| Wheelbase: |
Total: |
41ft 4in |
41ft 4in |
41ft 4in |
|
Engine: |
17ft 8in |
17ft 8in |
17ft 8in |
|
Tender: |
13ft |
13ft |
13ft |
| Weight (full): |
Total: |
96 tons 12cwt |
101 tons 7cwt |
101 tons 7cwt |
|
Engine: |
55 tons 14cwt |
58 tons 5cwt |
60 tons 9cwt |
|
Tender: |
40 tons 18cwt |
43 tons 2cwt |
40 tons 18cwt |
| Max. Axle Load: |
|
15 tons |
15 tons 9cwt |
16 tons 9cwt |
Preservation
The last of the "Long Toms" was withdrawn in 1937 and none have survived into preservation.
Models
Union Mills sell an N Gauge model of the Q2. This could probably be easily adapted to be a Q1 or a Q3.
Zenith Works produce 4mm scale kits of both the Q1 and the Q2.
Nu-Cast and Cotswold have both produced kits of the Q1/Q2 for OO gauge (4mm scale). It is unknown if the Cotswold
kit is still available. The NuCast moulds need renewal and is no longer considered economic.
Gladiator sell a kit of the Q1 for 7mm scale (O gauge).
Acknowledgements
Thank you to Mike Morant Collection for the colour illustration of Q1 No. 401.
|