During the 1920's Canadian Pacific experimented with a number of designs,
the 3100 series is a notable example of first engines built with a one
piece cast steel frame in Canada, a marked improvement over the hundreds
of individual parts in traditional frames. Despite its innovative design
only two were built (3100 and 3101) in 1928 in the Angus Shops in Montreal.
These 4-8-4s, built with 75" drivers, were designed as dual-purpose
locomotives. However, they were used continuously for 25 years on night
passenger trains between Toronto and Montreal. In keeping with CPR practice
they were later converted to burn oil.
CPR favored its fleet of Hudsons for passenger service and rejected the
Northerns because it concluded that they were too heavy and too slow for main
line passenger trains.
Both of these step-children from CPR's steam era survive today and are on
display, one at IPSCO Inc. in Regina, SK and the other at the National Museum
of Science and Technology in Ottawa, ON.
Class K1a (Locobase 244)
Data from 1930 Locomotive Cyclopedia tables and "Canadian Pacific class K-1-a, 3100-3101, Angus Shops, 1928" from Canadian Rail, No 487 (March-April 2002), pp. 78-79. (Thanks to Chris Hohl for sending a PDF of the Rail Canada articles.)
Boiler had feedwater heater and the axles had roller bearings. F H Howard, in "Selkirk to Connaught Or, from 2-10-4 to 4-10-2," The Old-Time Trains website (http://www.trainweb.org/oldtimetrains/selkirk.html, last accessed 25 October 2008) says that the K1s shared the same boiler with the T1 Selkirks. Its smokebox was flanked by tall smoke-lifters
These engines proved too heavy for all but the Montreal-Toronto line, where they pulled the night trains #21 Chicago Express and #22 Overseas Express for 25 years. Don Scott gives their later history in "Former Canadian Pacific Railway Passenger Services to Montreal Via State of Maine-Saint John-Halifax" of the ROCA Archives site -- http://www.trainweb.org/canadianrailways/articles/FormerCPRPassengerServicesToMontreal04.htm, last accessed 25 October 2008.
Scott reports they were supplanted on Montreal-Toronto runs by diesels in the mid-1950s. Hopes to run them on Montreal-St John service clear through to Saint John in New Brunswick reportedly ran afoul of the US ICC's reluctance to allow them to operate in Maine. So their portion of the run ended in Megantic, Quebec. Scott adds: "CPR later sent them to Western Canada and were converted to oil burners with 3101 on passenger trains Winnipeg-Moose Jaw, Sask. and other runs and 3100 shown as freight service"
In late 2007, a Canadian Pacific survey team was to visit IPSCO's 3101, on display outside in Regina, Saskatchewan, to see if it could be restored to service.