Class F (Locobase 827)

Data from Baldwin Locomotive Works Specification for Engines, as digitized by the DeGolyer Library of Southern Methodist University Volume 12, p. 2. Works numbers were 6591 in January 1883; 6594 in February; 6744 in May; 6796, 6817-6818 in June; and 6988, 7000, and 7002 in October.

With drivers as small as these, it's not really surprising that this class was later converted to G-class 0-8-0s.

Class F-1 (Locobase 829)

Data from DeGolyer, Vol 14, p. 220 and Vol 15, 148. See also John K Brown, The Baldwin Locomotive Works, 1831-1915: A Study in American Industrial Practice (Baltimore: Johns Hopkins University Press, 1995), pp. 78-80. . Works numbers were 9505-9508, 9511, 9514-9516, 9518, 9520, 9524 in August 1888; 9526, 9529 in October; 10000 in May 1889; 10440-10441, 10444-10448, 11305-11306, 11320, 11847, 11914, 11916, 11920, 11948 in November.

John Brown cites this class as an example of Baldwin's ability to take a new design used by one railroad and adapt it to another, often with mutually beneficial results. As noted in Locobase 9424, G W Cushing, new manager of the Reading, ordered this class in 1888. The design broke precedent on the Reading both for its size and for the use of conventional layout. The boiler in particular was quite large for the time. Brown reports (p. 78): "Baldwin built the custom order and then sold thirteen more engines of Cushing's original design to the Northern Pacific. Here a western line, completed only six years earlier, took advantage of the technical expertise of the fifty-year-old Philadelphia & Reading."

Brown's chronology, as presented on p 78 and on the caption of Locomotive 10000 on p 80 skips the first set of thirteen, which were ordered in June 1888. His point stands, however, as that order came after Cushing's earlier request. In the caption, Brown also supplies the useful addendum that the order included the Westinghouse air brake, Eames vacuum brake, and Westinghouse's train signal.

Three (50-52) were converted to Vauclain compounds for three years (1899-1902), then converted back to simple-expansion engines. As compounds, they had 15 x 28 HP cylinders, 25 x 28 LP cylinders.

Seven were sold in November 1925 to the Spokane, Portland & Seattle as their N-4 class and number 300-305, 315.

Class F-2 (Locobase 830)

Data confirmed by locomotive diagrams from 1900 hosted on http://www.nprr.org/Steam%20Diagrams/Forms/AllItems.aspx (7 Feb 2004). See also Baldwin Locomotive Works Specification for Engines, 1888, as digitized by the DeGolyer Library of Southern Methodist University Vol 14, 204. Works numbers were 9614 and 9625 in November 1888.

These Consolidations went to the Washington & Columbia River when that railroad bought the O & WT in November 1892. The W & CR folded into the Northern Pacific in July 1907 and these locomotives were renumbered 498-499, then 100-101, and finally 82-83. 82 was rebuilt as an 0-8-0 switcher while 83 was scrapped in July 1928.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class F-3 (Locobase 832)

Data confirmed by locomotive diagrams from 1900 hosted on http://www.nprr.org/Steam%20Diagrams/Forms/AllItems.aspx (7 Feb 2004).

NY Loco builder information from JF Webber's compilation as supplied by Allen Stanley in March 2004. The first of MU's class of Consolidations was works #455 (February 1889). Six months later the rest of the class rolled out of the Rome shops as works #498-503.

Once the Northern Pacific took over, these 2-8-0s were renumbered frequently, many 3 times over. One - works #501 - was operated by the Seattle & International as their #10, then served with the Northern Pacific, and finally on the Frisco (St Louis-San Francisco).

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class F-4 (Locobase 828)

Data confirmed by locomotive diagrams from 1900 hosted on http://www.nprr.org/Steam%20Diagrams/Forms/AllItems.aspx (7 Feb 2004). The diagram notes that #94 had 19 1/2" cylinders.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class F-5 (Locobase 837)

Data confirmed by locomotive diagrams from 1900 hosted on http://www.nprr.org/Steam%20Diagrams/Forms/AllItems.aspx (7 Feb 2004) and supplemented by NP to 1944 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Boiler pressure later increased to 165 psi.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class F-7 (Locobase 831)

Data confirmed by locomotive diagrams from 1900 hosted on http://www.nprr.org/Steam%20Diagrams/Forms/AllItems.aspx (7 Feb 2004). This is an unusual design with longer tubes.

Class F-8 (Locobase 833)

Data from a 1944 Northern Pacific Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

This is an ex-Pennsylvania Railroad locomotive class.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class Y (Locobase 835)

Data from a 1944 Northern Pacific Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Delivered as compounds in 1898, rebuilt and superheated in 1917 to the dimensions shown.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class Y-1 (Locobase 6559)

Data from a 1944 Northern Pacific Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

These were Alco's first tandem-compound locomotives. Each side's HP and LP cylinders were cast as a single unit with the HP cylinder immediately ahead of the larger LP cylinder. The piston valve used for HP steam used internal admission while its LP counterpart used external admission. They had the same diameter and like the pistons below shared the same rod.

The long stroke meant that the LP volume could never be large enough to make full use of the HP exhaust.

Simpled and superheated in 1917; see Locobase 833.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class Y-1 - superheated (Locobase 836)

Data from a 1944 Northern Pacific Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Delivered as compounds in 1900, rebuilt 1917 to the dimensions shown. Very similar to the Y-class rebuilds with slightly longer tubes but the same superheater.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class Y-2 (Locobase 838)

Data from Railroad Gazette of 30 August 1901.

These followed the Y-1s described in Locobase 6559. A big difference was the provision of taller drivers and the use of fewer, but longer boiler tubes.

These were soon converted to 2-cylinder simple engines with much lower boiler pressure.

Class Y-3 (Locobase 839)

Data from Railroad Gazette, 30 August 1901.

4-cylinder tandem compounds built for low-speed drag freight. As such they differed from the Y-2s delivered at the same time (Locobase 838), according to RG. Additional data from AERJ June 1903. Firebox heating surface included 28 sq ft of arch tubes.

These were soon converted to 2-cylinder simple locomotives.

Class Y-4 (Locobase 840)

Data from a 1944 Northern Pacific Locomotive Diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Somewhat smaller than the earlier Y classes, but fitted with much taller drivers.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class Y-4 (Locobase 10272)

4-cylinder tandem compounds built for low-speed drag freight. As such they differed from the Y-2s delivered at the same time, according to RG 30 August 1901. Additional data from AERJ June 1903. Firebox heating surface included 28 sq ft of arch tubes.

These were soon converted to 2-cylinder simple locomotives.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Class Y-5 (Locobase 841)

Data from NP 1 -1929 Locomotive Diagrams supplied in May 2005 by Allen Stanley.

The last of the Y series of Consolidations, this set was delivered with two simple-expansion cylinders.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface from the baldwin_steam site.