In 1937, the ACL received 12 new Class R-1 4-8-4s from the Baldwin Locomotive Works. They were assigned road numbers 1800 through 1811 and were immediately put into passenger service. These new 4-8-4s began to handle trains with as many as 21 heavyweight cars, eliminating the need for double-heading and running extra sections of many of the Richmond, VA to Jacksonville, FL "Specials".
The ACL was very disappointed with their R-1s, and returned them to Baldwin for better counterbalancing of the 80 inch drive wheels. It seems the R-1s, as delivered, had a bad dynamic augment. It was so bad that it was even worse than the Norfolk & Western's J class 4-8-4s with their low 70 inch drive wheels. Even after Baldwin checked their math, and put new disk drivers on the ACL R-1s, they still had unacceptable amounts of dynamic augment at high speeds. As soon as the ACL could replace them with EMD E-3 and E-6 diesel electrics, the Standard Railroad of the South put its latest and largest steamers in freight service.
Firebox was loaded with supplemental heating surface. In addition to the firebox area of 272 sq ft, R-1s had 127 sq ft in the combustion chamber and 168 sq ft in thermic syphons in both the firebox and combustion chamber.
The R-1s had all the latest features including cast-steel frame and roller bearings on the driving axles. But Baldwin overestimated the amount of counterbalancing these engines required, which led to pounding at high speeds. In fact, says http://www.awod.com/galery/rwav/whodom/back.html, at high speed "...the main drivers actually left the rails and repeatedly slammed back down, kinking rails and damaging track alignment for miles." It took time, but eventually the solution was found in reducing the counterbalancing.
Six of the class (1800-1801, 1806-1809) ran even more smoothly once they were fitted with lightweight pistons by Timken, piston rods, cross heads, and, probably most important, tapered main rods with roller bearing wrist pins.
The website (consulted in Sept 2001) says that these engines easily hit 90 mph in passenger service and probably topped 100 at times. In fast freight service, an 1800 was rated at 6,200 tons on the Richmond-Jacksonville main line.
Don Ball (Portrait of the Rails, 1972) says: "An engine I regret never having seen ...This Baldwin, judging from photos, had to be about the most handsome steam power in the south." Retired in 1951-1952.
|Specifications by Steve Llanso|
|Railroad||Atlantic Coast Line (ACL)|
|Locomotive Length and Weight|
|Ratio of driving wheelbase to overall engine wheebase||0.43|
|Overall Wheelbase (engine & tender)||97.92'|
|Axle Loading (Maximum Weight per Axle)||65792 lbs|
|Weight on Drivers||263127 lbs|
|Engine Weight||460270 lbs|
|Tender Light Weight||435000 lbs|
|Total Engine and Tender Weight||895270 lbs|
|Tender Water Capacity||24000 gals|
|Tender Fuel Capacity (oil/coal)||27 tons|
|Minimum weight of rail (calculated) on which locomotive could run||110 lb/yard|
|Geometry Relating to Tractive Effort|
|Boiler Pressure||275 psi|
|Cylinders (dia x stroke)||27" x 30"|
|Tractive Effort||63901 lbs|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||4.12|
|Firebox Area||568 sq. ft|
|Grate Area||97.75 sq. ft|
|Evaporative Heating Surface||4753 sq. ft|
|Superheating Surface||1425 sq. ft|
|Combined Heating Surface||6178 sq. ft|
|Evaporative Heating Surface/Cylinder Volume||239.08|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||26881|
|Same as above plus superheater percentage||33064|
|Same as above but substitute firebox area for grate area||192126|