NDEM: Central Mexicano / Internacional Mexicano / Interoceanico / Mexican Coal & Coke / Nacional Mexicano / Nacional de Mexico / Nacional de Tehuantepec / Veracruz al Pacifico 4-6-0 Locomotives in Mexico


Class Details by Steve Llanso of Sweat House Media

Class 148 / F-33 (Locobase 11934)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley. Works numbers were 2580-2584 in October 1895.


Class 15/F-19 (Locobase 11930)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley. See also DeGolyer, Volume 19, p. 22; and "The Tehuantepec Railroad-Its Importance as a Competitor for Transcontinental Traffic", American Engineer and Railroad Journal, Volume 69, No 8 (August 1895), pp. 351-352. Works numbers were 14222-14223 in February 1895.

At the time Baldwin delivered these two Ten-wheelers, exploitation of Mexican oil suitable for locomotive fuel hadn't begun in the Tehauntepec region. So the locomotives were set up as wood-convertible-to-coal burner. In later years, the two engines would burn oil and the tender carried 1,244 US gallons (4,708 litres) of oil. The 1895 specs also tasked Baldwin to build in the capacity for the engines to "be changed to compounds at least possible trouble."

When the NdeT was taken into the national fold by the Nacional de Mexico (NdeM) in 1908, the two 4-6-0s were renumbered 44-45. Not long afterward, the glowing prospects for continued tranquility foreseen in the 1895 prospectus magnified the advantages suggested by slightly shorter travel distances by Isthmus of Tehuantepec rail than by Isthmus of Panama ship were dashed by a long civil war.

In the fleet-wide renumbering of 1930, these two received 517-518.

When they reached the end of careers that had spanned nearly 60 years, both engines were sold to the Secretatia de Comunicaciones y Obras (S C O P), which renumbered them twice - 23018-23019 and 73212-73213.


Class 152 / F-09 (Locobase 12020)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 17, p. 217. Works numbers were 12827-12828, 12833-12834, 12839, 12850 in July 1892.

This septet of Ten-wheelers followed the trend to operating Vauclain compounds. The compounding ratio stood a little lower than most such locomotives. The 8" diameter piston valves were commensurate in relative size with the narrow-gauge locomotive they served.

By 1903, the compound-cylinder arrangement had been replaced by two simple-expansion 16"x 20" cylinders.


Class 162/F-25 (Locobase 2890)

Data from Catalogue Descriptive of Simple and Compound Locomotives built by Brooks Locomotive Works, Dunkirk, NY (Buffalo, NY: Matthew-Northrup Company, 1899). Works numbers were 2731-3735, 2745-2764.

Builder info from B.Rumary, 25 Kingscombe, Gurney Slade, Radstock, BA3 4TH, ENGLAND and Jeremy Lambert as supplied by Allen Stanley in March 2004.

This large class followed an earlier batch from 1895 (works numbers 2580-2584) as road #147-151. They had 20" x 24" cylinders and 56" drivers. See Locobase 11947 for a single 20" x 26" with identical dimensions.

As delivered, the 162s had 187.7 sq ft of firebox heating surface, but a later addition of arch -tubes increased the area to that shown in the specifications.


Class 163 / F-04 (Locobase 12259)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 21, p. 135. Works numbers were 15749-15750 in February 1898.

163 was sold in 1909 to the Interoceanic as their 37 and then to the Mexicano del Sur as #23. 23 returned to the NdeM with #264 (later 102) and served the railroad until 1945.

164 had a much shorter career, apparently being demolished or wrecked in the revolutionary period between 1914 and 1920.


Class 172 / F-09 (Locobase 12321)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 21, p. 135. Works numbers were 16468-16470 in January 1899.

Locobase 12259 shows 2 earlier simple-expansion Ten-wheelers; this trio was built to the same design, but used a Vauclain-compound system. All 3 were reported lost in the 1914-1920 revolutionary struggle.


Class 175 / F-09 (Locobase 12380)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 22, p. 197. Works numbers were 17270-17271 in December 1899; 17319-17320, 17361-17362 in January 1900.

Seven years after Baldwin had supplied 7 Vauclain compound Ten-wheelers to the metre-gauge network within the Nacional de Mexicano (Locobase 12020), the company ordered another with very similar dimensions. Boiler pressure rose a bit, but so did the driver diameter, so the locomotives generated about the same amount of power. Theoretically, they could run a bit faster.

Locobase is not sure if these were rebuilt as simple-expansion locomotives.


Class 23 / F-22 (Locobase 11549)

Data from Baldwin Locomotive Works Specification for Engines, 1903, as digitized by the DeGolyer Library of Southern Methodist University Vol 26, p. 37. ; 20270

20271 in April 1902; 23079, 23101, 23108-23109 in October 1903, 23119 in November.

These were Ten-wheel freighters with small grates and fireboxes.

The VC al P had been chartered in West Virginia in 1898 and built a main line from Cordoba (70 miles east of Mexico City) to Santa Lucrezia, where it linked to the Tehuantepec National Railway, as well as continuing on to Salina Cruz on the Pacific. In April 1904, the Mexican government took over the road in what appears to have been an offer that the Maryland Trust Company couldn't refuse. The settlement was substantial enough to retire all of the railroad's outstanding debt and return some of the investment to its backers.

eased it to the FC Vera Cruz al Istmo (Vera Cruz & Isthmus). In 1913 the Nacional de Mexico acquired the VC al I.


Class 28 (Locobase 3238)

Data from "Locomotives for the Interoceanic Railway, Mexico", Railroad Gazette, Volume 30, No 40 (7 October 1898), p. 721. Works numbers were 4790-4791 in July 1898.

Outside-frame cross-compound Ten-wheelers with slide valves, straight boilers. Fuel was coal briquettes. Like the Consolidations delivered in the same year, these were all-steel engines, with a steel boiler and firebox, steel cab, drivers, driving boxes.

Note: The reports from the period credited this design with tubes measuring 10 ft 7 in., but Locobase found that adding a foot to the tube length brought the tube area in line with the heating surface measurements given in the same articles.


Class 34/F-23 (Locobase 11132)

Data from Schenectady Locomotive Works, Illustrated Catalogue of Simple and Compound Locomotives (Philadelphia: J B Lippincott, 1897), pp. 78-79. Works numbers were 3886-3893 in September 1892.

NdeM sold the 278 to the FC Rio Mayo in May 1922 as their #1.


Class 39/F-23 (Locobase 11932)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley.

Some time after Schenectady supplied the eight Ten-wheelers to the Internacional Mexicano (Locobase 11132), the original boiler and firebox were replaced or renewed. The new grate grew slightly while the boiler gave up 27 of its 250 small tubes. The 767 now raised steam with oil rather than coal.

An unusual difference between old and new was the drop in weight. Adhesion weight declined by 14,800 lb (6,173 kg) and engine weight decreased by 11,500 lb (5,216 kg). The greater weight gain over the drivers seems likely to be due to the new boiler.


Class 40/F-13 (Locobase 11927)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley.


Class 92 (Locobase 12782)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 27, p 253. Works number was 25502 in April 1905.

This Ten-wheeler used the same camelback boiler and grate design as the Sonora locomotive described in Locobase 12439, but rolled on smaller drivers and operated at 20% higher boiler pressure to provide freight power.

When the MC&C was absorbed by the Nacional de Mexico in 1911, the 92 was renumbered 376. The engine was retired in August 1924.


Class F / F-22 (Locobase 11931)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley. See also DeGolyer, Volumes 23, p. 94 and 27, p. 36. Works numbers were 18184, 18189 in September 1900; 20270-20271 in April 1902; 23079, 23101, 23108-23109 in October 1903; 23119 in November..

Not long after the delivery of the last of these freight Ten-wheelers, the VP al P was taken over by the Mexican government and reorganized as the Vera Cruz y Istmo. Twenty-one years later the 8 was retired, but the other eight were absorbed by the Nacional de Mexico and given road numbers 759-766.


Class F-010 / F-05 (Locobase 11889)

Data from NdeM 1926ca Locomotive Diagrams supplied in December 2010 by Allen Stanley. Works numbers were 1690-1691 in December 1886 and 1698-1699 in January 1887.

This pair originally was delivered by Cooke in 1887 to International Mexicano. Locobase is certain, however, that the specifications presented in the 1926 book reflect the installation of a new boiler and the fitting of Walschaert radial valve gear at a later date.


Class F-011 / F-06 (Locobase 11890)

Data from NdeM 1926ca Locomotive Diagrams supplied in December 2010 by Allen Stanley.

Like the Ten-wheelers shown in Locobase 11889, this locomotive's specifications likely reflect an updated installation from the original engine supplied in 1895. The changes in this locomotive may have been more limited, possibly encompassing only the substitution of the Walschaert valve gear in place of the original link motion.


Class F-011 / F-08 (Locobase 11632)

Data from Baldwin Locomotive Works Specification for Engines, 1888, as digitized by the DeGolyer Library of Southern Methodist University Vol 15, p. 110. Works numbers were 10094-10096 in July 1889; 10578 in January 1890. See also NdeM 1926ca Locomotive Diagrams supplied in December 2010 by Allen Stanley.

This batch of Ten-wheelers operated on the skinny gauge for over 5 decades. Over time they were fitted with Walschaert valve gear and a different boiler. The firebox heating surface also grew substantially to 211 sq ft, a figure Locobase has difficulty accounting for in such a small locomotive.

They were retired in 1946 (7), 1948 (6, 5), and 1949 (8).


Class F-011 / F-08 (Locobase 11891)

Data from Baldwin Locomotive Works Specification for Engines, 1888, as digitized by the DeGolyer Library of Southern Methodist University Vol 15, p. 110. Works numbers were 11211, 11220-11221, 11240 in September 1890.

Locobase 11632 shows the 1889 batch of Ten-wheelers supplied by Baldwin to Interoceanic. This entry shows the 1890 engines, which had smaller boilers but larger fireboxes. The 160-psi boiler pressure may reflect a later boiler upgrade.


Class F-016/F-013 (Locobase 11893)

Data from NdeM 1926ca Locomotive Diagrams supplied in December 2010 by Allen Stanley. See also DeGolyer, Volume 74, pp. 398+. (Thanks to Wes Barris of steamlocomotive.com for his 5 August 2019 email querying the commentary that said this class was outfitted with Walschaert gear.) Works numbers were 57938-57943 in July 1924; 57962-57965 in August.

This oil-burning passenger Ten-wheeler design came late in the day for the wheel arrangement, but followed the traditional size and designs. Included were saturated boilers and outside radial gear as well as 8" (203 mm) piston valves.


Class F-07/ F-012 (Locobase 11892)

Data from NdeM 1926ca Locomotive Diagrams supplied in December 2010 by Allen Stanley.

At the same time Baldwin was supplying Ten-wheelers the FCI was buying from Schenectady as well. The specifications show a later boiler with a higher pressure and the installation of Walschaert radial valve gear.


Class F-10 (Locobase 11925)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley.

Locobase has only the diagram's assurance that this was a Pittsburgh-built locomotive to go by; there's no information on the number in the class or when it went into services. Its dimensions, boiler pressure, weights, etc. suggest a late 1890s production date or prehaps one as late as 1902-1903.


Class F-17 (Locobase 11929)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley.

Originally part of a large Cleveland, Cincinnati, Chicago & St Louis (Big Four) class of cross-compound Ten-wheelers. After its conversion to simple-expansion (Locobase 6765), this one engine arrived on the NdeM in 1928. It's shown here separately because of several changes in the boiler including a reduced tube count.


Class F-2 (Locobase 11921)

Data from 1950 NdeM Locomotive Diagrams Standard Gauge supplied in December 2010 by Allen Stanley.

Locobase 11920 shows the original Ten-wheeler design that stocked the FC Mexicano (aka Mexican National) in the 1880s. At some later date, the Mexicano reduced the cylinder diameter by an inch to 18".

Still later, the NdeM replaced the original boiler and firebox with a smaller vessel with more, but smaller-diameter tubes and and significantly less area in the firebox. Locobase wonders about the number of small tubes, however, because a boiler with 154 2" tubes would correspond in tube area almost exactly with the figures given in the diagram.


Class F-26 (Locobase 11933)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley.


Class F-32 (Locobase 11935)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley.


Class F-35 (Locobase 10766)

Data from NdeM 1946 Loco Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 26, p. 144.Works numbers were 24003, 24013, 24022, 24071, and 24102.

In 1904, Baldwin contributed a quintet of Ten-wheelers to the FCM that were slightly smaller than the Brooks engines of the previous couple of years (Locobase 10765). The original specs called for 360 boiler tubes, which would offered 2,639 sq ft (245.17 sq m) for a total of 2,784 sq ft (258.64 sq m) of evaporative heating surface area.

The class's fireboxes had less overall direct heating surface area, but used considerably larger grates to burn "run of mine coal high in fixed carbon". As often proved the case, operational experience prompted the FCM's William Burckel to send a letter recommending "heavier draft rigging front and back" in later engines. The originals may have not stood up to the snatching and jerking of rail cars.

After serving the FCM for a few years, the Ruta de Laredo's engines followed the FCM into the Nacional de Mexico. Under that herald, the class operated for almost five decades.

839 was scrapped first in August 1953 followed by 838 a month later. Three and half years later, 840 went to the ferro-knacker's yard, 837 going out of service in July 1957, while the class leader held on longest until its withdrawal in July 1958.


Class F-36 (Locobase 11937)

Data from NdeM 1950 Locomotive Diagrams Standard Gauge supplied in December 2010 from Allen Stanley.

Locobase 10765 describes the original, saturated-boiler variant. Unfortunately, the 1950 and 1961 books do not show the superheater area.


Class F-37 (Locobase 11947)

Data from NdeM 1950 Locomotive Diagrams Standard Gauge supplied in December 2010by Allen Stanley.

Locobase cannot say whether this was a locomotive supplied in addition to the large batch supplied in 1897 and detailed in Locobase 2890. The boiler and firebox dimensions wrer identical, but the cylinders in this single example had 2" more stroke and smaller drivers. Certainly the boiler was big enough to supply the extra cylinder volume.


Class F-38/F-34 (Locobase 10765)

Data from Angus Sinclair, Twentieth Century Locomotives (New York: Railway and Locomotive Engineering, 1904), pp. 591-593; and NdeM 1946 Locomotive Diagrams supplied in May 1905 by Allen Stanley from his extensive Rail Data Exchange collection. Works numbers were 25921-25930 in June 1902, and 26349-26353 in March 1903.

Sinclair describes the appearance of this locomotive as that "...of a well-proportioned machine, in which the clear-cut lines of the various mechanical details help to make up a harmonious whole." He also noted the design made extensive use of cast steel and piston valves set inside of the frame and operated by the link motion.

In a later incarnation, the class was converted to oil-firing and acquired a 2,963-gallon (11,215 litre) oil tender; they also rolled on 69" (1,753 mm) drivers. Six were retrofitted with fireboxes holding a single thermic syphon that contributed 34 sq ft (3.16 sq m) to firebox heating surface area. The change brought that figure to 216 sq ft (20.07 sq m).

Some were also superheated; see Locobase 10766. By 1946, only four saturated-boiler F-34s remained on the roster.


Class F-4/F-30/F-15 (Locobase 11928)

Data from NdeM 1950 Locomotive Diagrams supplied in December 2010 by Allen Stanley. Works numbers were 2810-2819 in September 1897.

All but four were retired in 1930. 747 (ex-303) was retired before 1946, but the other three--(748-749, ex-305-306, and 750 (ex-312) continued into the mid-to-late 1950s with 749-750 being retired in January 1955 and 748 going in March 1957.


Class FR-34 (Locobase 11936)

Data from NdeM 1950 Locomotive Diagrams Standard Gauge supplied in December 2010 from Allen Stanley.

Locobase 10765 describes the original, saturated-boiler variant. At least two of the superheated update shown here were fitted with radial valve gear.; Baker gear in 833, Walschaert in 834. As a result, 833's maximum valve travel was 6 1/2" (166 mm) and 834's remained at 6" (152 mm) These two did not have a thermic syphon in the firebox, but may have had an arch tube. Their adhesion weight came in 14,337 lb (6,503 kg) higher than the unmodified engines. Weight on the front truck ballooned from the original 39,000 lb to 57,855 (26,243 kg).

Unfortunately, the 1950 and 1961 books do not show the superheater area. Locobase's estimated superheater area is the average of several superheated Ten-wheelers of similar size with identical flue counts, diameters, and lengths.

Principal Dimensions by Steve Llanso of Sweat House Media
Class148 / F-3315/F-19152 / F-09162/F-25163 / F-04
Locobase ID11,934 11,930 12,020 2890 12,259
RailroadNacional Mexicano (NdeM)Nacional de Tehuantepec (NdeM)Nacional Mexicano (NdeM)Central Mexicano (NdeM)Nacional Mexicano (NdeM)
CountryMexicoMexicoMexicoMexicoMexico
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class528252
Road Numbers148-152 / 603-607 / 343-347 / 817+517-518152-158, 162162-186/770-795163-164
GaugeStdStd3'Std3'
Number Built528252
BuilderBrooksBurnham, Williams & CoBurnham, Williams & CoBrooksBurnham, Williams & Co
Year18951895189218971898
Valve GearStephensonStephensonWalschaertStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)11 / 3.3512.87 / 3.9212 / 3.6611 / 3.3512 / 3.66
Engine Wheelbase (ft / m)22.33 / 6.8123.33 / 7.1121.42 / 6.5323.33 / 7.1121.42 / 6.53
Ratio of driving wheelbase to overall engine wheebase 0.49 0.55 0.56 0.47 0.56
Overall Wheelbase (engine & tender) (ft / m)51.33 / 15.6545.62 / 13.9046.70 / 14.2351.33 / 15.65
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)113,000 / 51,25685,000 / 38,55556,000 / 25,401111,000 / 50,349
Engine Weight (lbs / kg)148,000 / 67,132113,000 / 51,25676,000 / 34,473147,500 / 66,905
Tender Loaded Weight (lbs / kg)93,300 / 42,32069,500 / 31,52585,000 / 38,555
Total Engine and Tender Weight (lbs / kg)241,300 / 109,452182,500 / 82,781232,500 / 105,460
Tender Water Capacity (gals / ML)4500 / 17.053000 / 11.363000 / 11.364500 / 17.053600 / 13.64
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)2564 / 9.701244 / 4.70 8.50 / 7.702564 / 9.70
Minimum weight of rail (calculated) (lb/yd / kg/m)63 / 31.5047 / 23.5031 / 15.5062 / 31
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)56 / 142260 / 152446 / 116860 / 152446 / 1168
Boiler Pressure (psi / kPa)180 / 12.40180 / 12.40180 / 12.40180 / 12.40190 / 13.10
High Pressure Cylinders (dia x stroke) (in / mm)20" x 24" / 508x61019" x 24" / 483x61010" x 20" / 254x50820" x 24" / 508x61014.5" x 20" / 368x508
Low Pressure Cylinders (dia x stroke) (in / mm)17" x 20" / 432x508
Tractive Effort (lbs / kg)26,229 / 11897.2922,093 / 10021.239884 / 4483.3124,480 / 11103.9514,763 / 6696.39
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.31 3.85 5.67 4.53
Heating Ability
Firebox Area (sq ft / m2)213 / 19.80133 / 12.3684.59 / 7.86206 / 19.1492.12 / 8.56
Grate Area (sq ft / m2)26.14 / 2.4317.16 / 1.5915 / 1.3926.14 / 2.4314.10 / 1.31
Evaporative Heating Surface (sq ft / m2)1764 / 163.941643 / 152.64894 / 83.092061 / 191.54901 / 83.74
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1764 / 163.941643 / 152.64894 / 83.092061 / 191.54901 / 83.74
Evaporative Heating Surface/Cylinder Volume202.14208.61491.74236.17235.71
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation47053089270047052679
Same as above plus superheater percentage47053089270047052679
Same as above but substitute firebox area for grate area38,34023,94015,22637,08017,503
Power L154465275345963765189
Power MT318.75410.45408.52379.91

Principal Dimensions by Steve Llanso of Sweat House Media
Class172 / F-09175 / F-0923 / F-222834/F-23
Locobase ID12,321 12,380 11,549 3238 11,132
RailroadNacional Mexicano (NdeM)Nacional Mexicano (NdeM)Veracruz al Pacifico (NdeM)Interoceanico (NdeM)Internacional Mexicano (NdeM)
CountryMexicoMexicoMexicoMexicoMexico
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class36528
Road Numbers172-174175-18023-27 / 762-76628-2934-41/35, 37-38, 40, 78-81/276-283
Gauge3'3'Std3'Std
Number Built36528
BuilderBurnham, Williams & CoBurnham, Williams & CoBurnham, Williams & CoSchenectadySchenectady
Year18991899190318981892
Valve GearStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)12 / 3.6612 / 3.6613.72 / 4.1813.17 / 4.0114.33 / 4.37
Engine Wheelbase (ft / m)21.42 / 6.5321.42 / 6.5324.25 / 7.3922.42 / 6.8324.75 / 7.54
Ratio of driving wheelbase to overall engine wheebase 0.56 0.56 0.57 0.59 0.58
Overall Wheelbase (engine & tender) (ft / m)46.70 / 14.2347.17 / 14.38
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)87,000 / 39,46358,000 / 26,30889,800 / 40,733
Engine Weight (lbs / kg)115,000 / 52,16390,500 / 41,050120,000 / 54,431
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)3600 / 13.643600 / 13.644000 / 15.153000 / 11.364000 / 15.15
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 4.50 / 4.10
Minimum weight of rail (calculated) (lb/yd / kg/m)48 / 2432 / 1650 / 25
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)46 / 116848 / 121950 / 127048 / 121955 / 1397
Boiler Pressure (psi / kPa)190 / 13.10190 / 13.10180 / 12.40200 / 13.80160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)10" x 20" / 254x50810" x 20" / 254x50818" x 24" / 457x61017" x 20" / 432x508 (1)19" x 26" / 483x660
Low Pressure Cylinders (dia x stroke) (in / mm)17" x 20" / 432x50817" x 20" / 432x50827" x 20" / 686x508 (1)
Tractive Effort (lbs / kg)10,433 / 4732.339999 / 4535.4823,795 / 10793.2414,659 / 6649.2223,209 / 10527.44
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.66 3.96 3.87
Heating Ability
Firebox Area (sq ft / m2)95.30 / 8.8695.30 / 8.86124 / 11.5282 / 7.62150.03 / 13.94
Grate Area (sq ft / m2)14.12 / 1.3114.12 / 1.3117 / 1.5815.30 / 1.4217.28 / 1.61
Evaporative Heating Surface (sq ft / m2)904 / 84.01904 / 84.011623 / 150.841131 / 105.111732 / 160.91
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)904 / 84.01904 / 84.011623 / 150.841131 / 105.111732 / 160.91
Evaporative Heating Surface/Cylinder Volume497.24497.24229.61430.52203.00
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation26832683306030602765
Same as above plus superheater percentage26832683306030602765
Same as above but substitute firebox area for grate area18,10718,10722,32016,40024,005
Power L138273994476037214267
Power MT361.86424.31314.27

Principal Dimensions by Steve Llanso of Sweat House Media
Class39/F-2340/F-1392F / F-22F-010 / F-05
Locobase ID11,932 11,927 12,782 11,931 11,889
RailroadNacional de Mexico (NdeM)Nacional de Tehuantepec (NdeM)Mexican Coal & Coke (NdeM)Veracruz al Pacifico (NdeM)Central Mexicano (NdeM)
CountryMexicoMexicoMexicoMexicoMexico
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class16184
Road Numbers39/79/76740-43/513-51692 / 3767-8, 17-18, 23-27/759-766261-262 / 103-104
GaugeStdStdStdStd3'
Number Built16184
BuilderNdeMAlco-PittsburghBurnham, Williams & CoBurnham, Williams & CoCooke
Year1903190519001886
Valve GearStephensonStephensonStephensonStephensonWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)14.33 / 4.3710.67 / 3.2512.50 / 3.8113.75 / 4.1913.17 / 4.01
Engine Wheelbase (ft / m)24.50 / 7.4720.50 / 6.2523.33 / 7.1124.25 / 7.3922.54 / 6.87
Ratio of driving wheelbase to overall engine wheebase 0.58 0.52 0.54 0.57 0.58
Overall Wheelbase (engine & tender) (ft / m)47.50 / 14.4845.58 / 13.8948.03 / 14.6443.21 / 13.17
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)75,500 / 34,24682,460 / 37,403118,000 / 53,52488,578 / 40,17873,723 / 33,440
Engine Weight (lbs / kg)109,500 / 49,668107,000 / 48,534151,000 / 68,493113,561 / 51,51097,196 / 44,087
Tender Loaded Weight (lbs / kg)90,000 / 40,82384,000 / 38,102120,000 / 54,43184,179 / 38,18377,404 / 35,110
Total Engine and Tender Weight (lbs / kg)199,500 / 90,491191,000 / 86,636271,000 / 122,924197,740 / 89,693174,600 / 79,197
Tender Water Capacity (gals / ML)4000 / 15.154000 / 15.156000 / 22.733994 / 15.133000 / 11.36
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)2825 / 10.703120 / 11.801637 / 6.202000 / 7.60
Minimum weight of rail (calculated) (lb/yd / kg/m)42 / 2146 / 2366 / 3349 / 24.5041 / 20.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)55 / 139756 / 142260 / 152450 / 127048 / 1219
Boiler Pressure (psi / kPa)160 / 11180 / 12.40200 / 13.80175 / 12.10175 / 12.10
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x66018" x 24" / 457x61019" x 26" / 483x66018" x 24" / 457x61016" x 20" / 406x508
Tractive Effort (lbs / kg)23,209 / 10527.4421,245 / 9636.5826,594 / 12062.8523,134 / 10493.4215,867 / 7197.16
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.25 3.88 4.44 3.83 4.65
Heating Ability
Firebox Area (sq ft / m2)141 / 13.10133 / 12.36176 / 16.36124 / 11.5297 / 9.01
Grate Area (sq ft / m2)17.90 / 1.6623 / 2.1476 / 7.0617 / 1.5814.36 / 1.33
Evaporative Heating Surface (sq ft / m2)1557 / 144.651563 / 145.261803 / 167.571623 / 150.78910 / 84.57
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1557 / 144.651563 / 145.261803 / 167.571623 / 150.78910 / 84.57
Evaporative Heating Surface/Cylinder Volume182.49221.12211.32229.61195.52
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2864414015,20029752513
Same as above plus superheater percentage2864414015,20029752513
Same as above but substitute firebox area for grate area22,56023,94035,20021,70016,975
Power L138885295628946284196
Power MT340.59424.70352.50345.56376.43

Principal Dimensions by Steve Llanso of Sweat House Media
ClassF-011 / F-06F-011 / F-08F-011 / F-08F-016/F-013F-07/ F-012
Locobase ID11,890 11,632 11,891 11,893 11,892
RailroadCentral Mexicano (NdeM)Interoceanico (NdeM)Interoceanico (NdeM)Nacional de Mexico (NdeM)Interoceanico (NdeM)
CountryMexicoMexicoMexicoMexicoMexico
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class154102
Road Numbers263 / 10530-34 / 6-8, 5144, 146, 152, 158/ 146, 152217-226/181-19028-29 / 11-12
Gauge3'3'3'3'3'
Number Built154102
BuilderCookeBurnham, Parry, Williams & CoBurnham, Parry, Williams & CoBaldwinSchenectady
Year18951889189019241889
Valve GearWalschaertStephensonStephensonBakerWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)13.17 / 4.0112.50 / 3.8112 / 3.6610.75 / 3.2813.17 / 4.01
Engine Wheelbase (ft / m)22.54 / 6.8721.83 / 6.6521.62 / 6.5920.25 / 6.1722.08 / 6.73
Ratio of driving wheelbase to overall engine wheebase 0.58 0.57 0.56 0.53 0.60
Overall Wheelbase (engine & tender) (ft / m)44.87 / 13.6845.21 / 13.7847.08 / 14.3543.06 / 13.12
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)58,000 / 26,30852,000 / 23,58758,025 / 26,32088,519 / 40,15266,495 / 30,162
Engine Weight (lbs / kg)87,000 / 39,46370,000 / 31,75280,135 / 36,34971,385 / 32,38092,455 / 41,937
Tender Loaded Weight (lbs / kg)67,000 / 30,39177,165 / 35,0013000 / 136187,450 / 39,667
Total Engine and Tender Weight (lbs / kg)154,000 / 69,854157,300 / 71,35074,385 / 33,741179,905 / 81,604
Tender Water Capacity (gals / ML)3000 / 11.362500 / 9.472500 / 9.473000 / 11.363000 / 11.36
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)2041 / 7.701550 / 5.901250 / 4.701972 / 7.50
Minimum weight of rail (calculated) (lb/yd / kg/m)32 / 1629 / 14.5032 / 1649 / 24.5037 / 18.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)48 / 121948 / 121946 / 116849 / 124548 / 1067
Boiler Pressure (psi / kPa)175 / 12.10130 / 9160 / 11180 / 12.40175 / 12.10
High Pressure Cylinders (dia x stroke) (in / mm)16" x 20" / 406x50816" x 20" / 406x50816" x 20" / 406x50817" x 20" / 432x50816" x 20" / 406x508
Tractive Effort (lbs / kg)15,867 / 7197.1611,787 / 5346.5015,137 / 6866.0418,048 / 8186.4415,867 / 7197.16
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.66 4.41 3.83 4.90 4.19
Heating Ability
Firebox Area (sq ft / m2)89 / 8.2784.59 / 7.86109 / 10.13116 / 10.78119.64 / 11.12
Grate Area (sq ft / m2)15.31 / 1.4213.25 / 1.2314 / 1.3015.80 / 1.4718.23 / 1.69
Evaporative Heating Surface (sq ft / m2)978 / 90.89894 / 83.09839 / 77.971114 / 103.491124 / 104.46
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)978 / 90.89894 / 83.09839 / 77.971114 / 103.491124 / 104.46
Evaporative Heating Surface/Cylinder Volume210.13192.08180.27212.02241.50
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation26791723224028443190
Same as above plus superheater percentage26791723224028443190
Same as above but substitute firebox area for grate area15,57510,99717,44020,88020,937
Power L142802943364847395180
Power MT488.06374.32415.81354.08515.22

Principal Dimensions by Steve Llanso of Sweat House Media
ClassF-10F-17F-2F-26F-32
Locobase ID11,925 11,929 11,921 11,933 11,935
RailroadNacional de Mexico (NdeM)Nacional de Mexico (NdeM)Nacional de Mexico (NdeM)Nacional de Mexico (NdeM)Nacional Mexicano (NdeM)
CountryMexicoMexicoMexicoMexicoMexico
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class12392
Road Numbers739753703-725797-805815-816
GaugeStdStdStdStdStd
Number Built92
BuilderPittsburghBig FourNdeMAlco-CookeBrooks
Year1900189319021895
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)10.17 / 3.1011.92 / 3.6313.50 / 4.1114.92 / 4.5511 / 3.35
Engine Wheelbase (ft / m)20.46 / 6.2423.08 / 7.0323.65 / 7.2125.42 / 7.7523.33 / 7.11
Ratio of driving wheelbase to overall engine wheebase 0.50 0.52 0.57 0.59 0.47
Overall Wheelbase (engine & tender) (ft / m)46.37 / 14.1349.87 / 15.2046.73 / 14.2453.17 / 16.2151.33 / 15.65
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)83,227 / 37,751112,436 / 51,00064,000 / 29,030109,100 / 49,487111,000 / 50,349
Engine Weight (lbs / kg)110,969 / 50,335132,277 / 60,00086,000 / 39,009146,250 / 66,338147,000 / 66,678
Tender Loaded Weight (lbs / kg)105,160 / 47,700101,352 / 45,97362,400 / 28,304114,850 / 52,09593,300 / 42,320
Total Engine and Tender Weight (lbs / kg)216,129 / 98,035233,629 / 105,973148,400 / 67,313261,100 / 118,433240,300 / 108,998
Tender Water Capacity (gals / ML)4450 / 16.865000 / 18.942700 / 10.236000 / 22.734500 / 17.05
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)1515 / 5.702776 / 10.501548 / 5.903052 / 11.602564 / 9.70
Minimum weight of rail (calculated) (lb/yd / kg/m)46 / 2362 / 3136 / 1861 / 30.5062 / 31
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)51 / 129556 / 142256 / 142263 / 160056 / 1422
Boiler Pressure (psi / kPa)150 / 10.30165 / 11.40140 / 9.70180 / 12.40180 / 12.40
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x61019" x 24" / 483x61017.5" x 24" / 445x61020" x 26" / 508x66020" x 24" / 508x610
Tractive Effort (lbs / kg)19,440 / 8817.8521,699 / 9842.5115,619 / 7084.6725,257 / 11456.4026,229 / 11897.29
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.28 5.18 4.10 4.32 4.23
Heating Ability
Firebox Area (sq ft / m2)129.43 / 12.03172 / 15.99102.70 / 9.54128.84 / 11.97206 / 19.14
Grate Area (sq ft / m2)23.21 / 2.1631.50 / 2.9317 / 1.5817.21 / 1.6026.14 / 2.43
Evaporative Heating Surface (sq ft / m2)1506 / 139.961851 / 172.031200 / 111.521858 / 172.682061 / 191.54
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1506 / 139.961851 / 172.031200 / 111.521858 / 172.682061 / 191.54
Evaporative Heating Surface/Cylinder Volume213.06235.02179.60196.53236.17
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation34825198238030984705
Same as above plus superheater percentage34825198238030984705
Same as above but substitute firebox area for grate area19,41528,38014,37823,19137,080
Power L138845301335150025951
Power MT308.65311.82346.30303.23354.59

Principal Dimensions by Steve Llanso of Sweat House Media
ClassF-35F-36F-37F-38/F-34F-4/F-30/F-15
Locobase ID10,766 11,937 11,947 10,765 11,928
RailroadCentral Mexicano (NdeM)Nacional de Mexico (NdeM)Central Mexicano (NdeM)Central Mexicano (NdeM)Nacional de Mexico (NdeM)
CountryMexicoMexicoMexicoMexicoMexico
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class55411510
Road Numbers392-396/415-419/315-319/392-396/836-840844-897898400-414/300-324/377-391/821-835187-196/650-659/303-312/747-750
GaugeStdStdStdStdStd
Number Built55411510
BuilderBurnham, Williams & CoNdeMBrooksAlco-BrooksBrooks
Year19041903189719021897
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)13.67 / 4.1713 / 3.9611 / 3.3514.50 / 4.4211 / 3.35
Engine Wheelbase (ft / m)25 / 7.6224.33 / 7.4223.33 / 7.1125.42 / 7.7523.33 / 7.11
Ratio of driving wheelbase to overall engine wheebase 0.55 0.53 0.47 0.57 0.47
Overall Wheelbase (engine & tender) (ft / m)57.25 / 17.4551.44 / 15.6851.33 / 15.6556.29 / 17.1651.33 / 15.65
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)141,000 / 63,957147,337 / 66,831100,500 / 45,586133,000 / 60,328111,000 / 50,349
Engine Weight (lbs / kg)180,000 / 81,647159,394 / 72,300135,300 / 61,371172,000 / 78,018147,000 / 66,678
Tender Loaded Weight (lbs / kg)120,000 / 54,431110,231 / 50,00085,400 / 38,737108,000 / 48,98893,300 / 42,320
Total Engine and Tender Weight (lbs / kg)300,000 / 136,078269,625 / 122,300220,700 / 100,108280,000 / 127,006240,300 / 108,998
Tender Water Capacity (gals / ML)7000 / 26.525000 / 18.944000 / 15.157000 / 26.524500 / 17.05
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)2943 / 11.103103 / 11.802613 / 9.9012 / 10.902564 / 9.70
Minimum weight of rail (calculated) (lb/yd / kg/m)78 / 3982 / 4156 / 2874 / 3762 / 31
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)68 / 172763 / 160056 / 142268 / 172762 / 1575
Boiler Pressure (psi / kPa)200 / 13.80180 / 12.40180 / 12.40200 / 13.80180 / 12.40
High Pressure Cylinders (dia x stroke) (in / mm)20" x 28" / 508x71120" x 28" / 508x71120" x 26" / 508x66020" x 28" / 508x71119" x 24" / 483x610
Tractive Effort (lbs / kg)28,000 / 12700.6027,200 / 12337.7328,414 / 12888.3928,000 / 12700.6021,381 / 9698.27
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.04 5.42 3.54 4.75 5.19
Heating Ability
Firebox Area (sq ft / m2)144 / 13.38183 / 17.01206 / 19.14177 / 16.44192 / 17.84
Grate Area (sq ft / m2)46.75 / 4.3426.66 / 2.4826.14 / 2.4335.10 / 3.2626.14 / 2.43
Evaporative Heating Surface (sq ft / m2)2563 / 238.202739 / 254.552061 / 191.542754 / 255.852076 / 192.94
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2563 / 238.202739 / 254.552061 / 191.542754 / 255.852076 / 192.94
Evaporative Heating Surface/Cylinder Volume251.74269.03218.01270.50263.59
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation93504799470570204705
Same as above plus superheater percentage93504799470570204705
Same as above but substitute firebox area for grate area28,80032,94037,08035,40034,560
Power L173096783549381027170
Power MT342.84304.48361.49402.90427.22

Principal Dimensions by Steve Llanso of Sweat House Media
ClassFR-34
Locobase ID11,936
RailroadNacional de Mexico (NdeM)
CountryMexico
Whyte4-6-0
Number in Class2
Road Numbers833-834
GaugeStd
Number Built
BuilderNdeM
Year
Valve GearWalschaert or Sthrn
Locomotive Length and Weight
Driver Wheelbase (ft / m)14.50 / 4.42
Engine Wheelbase (ft / m)26.58 / 8.10
Ratio of driving wheelbase to overall engine wheebase 0.55
Overall Wheelbase (engine & tender) (ft / m)58.06 / 17.70
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)147,337 / 66,831
Engine Weight (lbs / kg)205,192 / 93,074
Tender Loaded Weight (lbs / kg)140,836 / 63,882
Total Engine and Tender Weight (lbs / kg)346,028 / 156,956
Tender Water Capacity (gals / ML)7000 / 26.52
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)2963 / 11.20
Minimum weight of rail (calculated) (lb/yd / kg/m)82 / 41
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)69 / 1753
Boiler Pressure (psi / kPa)200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)20.5" x 28" / 521x711
Tractive Effort (lbs / kg)28,991 / 13150.11
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.08
Heating Ability
Firebox Area (sq ft / m2)190 / 17.65
Grate Area (sq ft / m2)34 / 3.16
Evaporative Heating Surface (sq ft / m2)2030 / 188.59
Superheating Surface (sq ft / m2)375 / 34.84
Combined Heating Surface (sq ft / m2)2405 / 223.43
Evaporative Heating Surface/Cylinder Volume189.78
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation6800
Same as above plus superheater percentage7888
Same as above but substitute firebox area for grate area44,080
Power L113,665
Power MT613.41

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