These Twelve-wheelers were part of a short-lived trend in which six axles seemed better than five for a big freight hauler. They were fitted with a brick arch and noted for their size. On the other hand, compared to many later 4-8-0s, these engines had a relatively short stroke.
According to a website on immigration (of all sources and on an appropriate day to discover it!) -- http://web.telia.com/~u85435856/emigration/minnesota2.html, accessed 4 July 2007 -- these were the biggest of the time.
To be precise, Todd Lindahl's account of his family history includes the following caption:"'My grandfather Gust (Franz Gustaf but preferred to be called "Gust"). The picture was taken in the Duluth & Iron Range back shops in 1901. Gust is standing on the running board of the locomotive just to the left of the bell. The locomotive is number 70, a 4-8-0 mastodon type engine. When these engines arrived in 1893 they were the largest freight engines ever built.'"
The entire class remained in service into the late 1920s. All were withdrawn and scrapped by the end of 1933.
|Specifications by Steve Llanso of Sweat House Media|
|Railroad||Duluth & Iron Range (DM&IR)|
|Number in Class||30|
|Locomotive Length and Weight|
|Ratio of driving wheelbase to overall engine wheebase||0.61|
|Overall Wheelbase (engine & tender)||51.58'|
|Axle Loading (Maximum Weight per Axle)||0|
|Weight on Drivers||139000 lbs|
|Engine Weight||169000 lbs|
|Tender Light Weight||73185 lbs|
|Total Engine and Tender Weight||242185 lbs|
|Tender Water Capacity||3168 gals|
|Tender Fuel Capacity (oil/coal)||7.2 tons|
|Minimum weight of rail (calculated)||58 lb/yard|
|Geometry Relating to Tractive Effort|
|Boiler Pressure||170 psi|
|Cylinders (dia x stroke)||22" x 26"|
|Tractive Effort||33674 lbs|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||4.13|
|Firebox Area||189.70 sq. ft|
|Grate Area||31.50 sq. ft|
|Evaporative Heating Surface||2402 sq. ft|
|Combined Heating Surface||2402 sq. ft|
|Evaporative Heating Surface/Cylinder Volume||209.98|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||5355|
|Same as above plus superheater percentage||5355|
|Same as above but substitute firebox area for grate area||32249|