In 1912 and 1913, the shops built forty more 2-8-2s. This group was designated as Class L-2 and assigned numbers 8000 through 8039. They were similar to the Class L-I "Mikados" except the cylinder diameter was 26 inches, which raised the tractive effort to 54,725 pounds. During 1912 the CMStP&P had the American Locomotive Company build 115 of the Class L-2 locomotives and assigned them road numbers 8040 through 8154 and in 1914, ordered another twenty-five from ALCO, which were delivered the same year and given road numbers 8155 through 8179. The class L-2 locomotives had 63" diameter drivers, 26" x 30" cylinders, a 200 psi boiler pressure and they exerted 54,725 pounds of tractive effort and each weighed 275,000 pounds. The firebox was 258 square feet and the evaporative heating surface was 3,050 square feet and with the superheater the combined heating surface was 3,690 square feet..
In 1918 and 1919, the USRA assigned 100 USRA "Mikado-Heavy" type locomotives to the CMStP&P. This was in fact 43% of this type of locomotive assigned by the USRA. These locomotives were assigned road numbers 8600 through 8699 and were designated as Class L-3. The Class L-3 locomotives had 63" diameter drivers, 27" x 32" cylinders, a 190 psi boiler pressure and they exerted 59,800 pounds of tractive effort and each weighed 325,000 pounds.
The USRA "Mikado-Heavy" Class L-3 locomotives did well on the CMStP&P, but after the War 200 more "Mikados" were ordered from the Baldwin Locomotive Works. These locomotives were very close copies of the Class L-2. Baldwin delivered 100 between 1920 and 1921 and they were assigned road numbers 8200 through 8299 and Baldwin delivered another 100 between 1922 and 1923 and these were given numbers 8300 through 8399. The Class L-2
There are no surviving Milwaukee Road 2-8-2 "Mikado" type locomotives.
|Class||Qty.||Road Numbers||Later Numbers||Year Built||Builder||Notes|
These were, according to Jim Scribbins (in Drury, 1993), "basically enlarged Prairies [2-6-2]." 65 sq ft of direct heating surface came from the combustion chamber.
Most stayed in service until the 1950s.
According to Jim Scribbins writing in Drury (1993), this Mikado design suited the Chicago, Milwaukee, St Paul & Pacific's requirements very well. The Milwaukee shops built 40 in their shops and bought 180 (155 from Brooks in 1912 and 25 from Schenectady in 1914).
After World War I, Baldwin supplied 200 more in 1920-1923 to slightly different designs; see Locobases 15196 and 15197.
Locobase doesn't know why the class began retiring as early as the 1930s, but can tell that some carried on to the end of steam.
September 53624-53625, 53658-53660, 53678-53680, 53708-53711, 53754-53756
October 53819-53821, 53839-53843, 53867, 53913-53917
November 53937-53939, 53970-53973, 54000, 54036-54044, 54093-54097, 54099, 54120, 54125-
December 54152-54160, 54192-54194, 54197
January 54287-54289, 54315-54320, 54348-54359
When the Milwaukee decided to increase its Mikado motive power stock six years after building its own and buying from Alco (Locobase 1191), it went to Eddystone. The design had the same power dimensions and weighed about the same. Piston valves still measured 14" (356 mm) in diameter and the firebox still had 26 sq ft (2.4 sq m) of arch tubes. Also the boiler's distribution of tubes and flues was unchanged.
But the valves were actuated by Baker-Pilliod's radial gear, the grate area grew a bit due a slightly longer grate, the combustion chamber gained four inches (102 mm) and increased its contribution to heating surface area to 65 sq ft (6.05 sq m). It was delivered with a Duplex automatic stoker.
A "Hereafter" note from 24 April 1924 stating that that "No welding whatever will be permitted on forgings" suggests some in-service incidents that ended badly.
Well-suited to the Milwaukee's demands, as were all of the L2s, all but a few L2-as served into the 1950s. The 8280 was withdrawn in July 1935 and 8289 was retired in March 1944. Of the rest, several were retired in late 1949, the bulk in 1950-1953, and the last few in December 1954.
September 55605-55616, 55663-55668
May 56518-56523, 56577-56586
July 56759-56765, 56831-56836
August 56907-56911, 56984-56991
September 57062-57066, 57082-57083, 57171-57181
October 57249-57252, 57265-57365
Locobase had detected a relative insufficiency in superheater heating surface area compared to many other Mikados of the period and apparently so did the Milwaukee some 90 years earlier. The last L2s they procured came from Baldwin (as had the L2a shown in Locobase 15196), but these had boiler changes aimed at remedying that shortcoming.
Like all of the Milwaukee's L2s, this class of -bs satisfied Milwaukee Road requirements for decades and all operated into the 1950s. The first to retire was withdrawn in January 1950, the last nineteen were withdrawn as a group six years later in January 1956.
|Specifications by Steve Llanso|
|Railroad||Milwaukee Road (CMStP&P)||Milwaukee Road (CMStP&P)||Milwaukee Road (CMStP&P)||Milwaukee Road (CMStP&P)|
|Road Numbers||8500-8519||8000-8179||8200-8299 / 500-598||8300-8399|
|Locomotive Length and Weight|
|Ratio of driving wheelbase to overall engine wheebase||0.47||0.47||0.47||0.47|
|Overall Wheelbase (engine & tender)||65.60'||66.69'||66.69'||70.54'|
|Axle Loading (Maximum Weight per Axle)||56300 lbs|
|Weight on Drivers||201000 lbs||216500 lbs||219000 lbs||219000 lbs|
|Engine Weight||260500 lbs||275000 lbs||289000 lbs||289000 lbs|
|Tender Light Weight||154000 lbs||156000 lbs||155000 lbs||180000 lbs|
|Total Engine and Tender Weight||414500 lbs||431000 lbs||444000 lbs||469000 lbs|
|Tender Water Capacity||8000 gals||8500 gals||8500 gals||10000 gals|
|Tender Fuel Capacity (oil/coal)||14 tons||11 tons||12 tons||16 tons|
|Minimum weight of rail (calculated) on which locomotive could run||84 lb/yard||90 lb/yard||91 lb/yard||91 lb/yard|
|Geometry Relating to Tractive Effort|
|Boiler Pressure||200 psi||200 psi||200 psi||200 psi|
|Cylinders (dia x stroke)||24" x 30"||26" x 30"||26" x 30"||26" x 30"|
|Tractive Effort||46629 lbs||54724 lbs||54724 lbs||54724 lbs|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||4.31||3.96||4.00||4.00|
|Firebox Area||282 sq. ft||258 sq. ft||310 sq. ft||311 sq. ft|
|Grate Area||48.80 sq. ft||48.80 sq. ft||49.12 sq. ft||48.80 sq. ft|
|Evaporative Heating Surface||3614 sq. ft||3050 sq. ft||3106 sq. ft||2950 sq. ft|
|Superheating Surface||640 sq. ft||645 sq. ft||720 sq. ft|
|Combined Heating Surface||3614 sq. ft||3690 sq. ft||3751 sq. ft||3670 sq. ft|
|Evaporative Heating Surface/Cylinder Volume||230.07||165.45||168.48||160.02|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||9760||9760||9824||9760|
|Same as above plus superheater percentage||9760||11419||11494||11712|
|Same as above but substitute firebox area for grate area||56400||60372||72540||74640|