8.6.8 Northern Pacific GP 7 No.558

Prototype Information

EMD had a good success with dieselizatiion of freight service with their FT cab and booster units. WW2 production restrictions limited EMD to building FT's, ALCO to building S1 and S2 yard switchers and the RS1 road switcher. 

EMD's first effort into the road switcher market was the BL2 model. Its design (a cross between a cab unit and road unit) was was a marketing failure. The GP7 marked EMD's second entry into the road switcher market in 1949. Although it was late to the party, with similar road switchers from ALCO, Baldwin and Fairbanks-Morse having been in production for several years by that point, it ultimately became the most successful of the bunch.

The NP was not inclined to rush dieselization on its branch lines. Mainline passenger and freight trains wer mostly dieselized with F3 and F7 units. Steam locomotives demoted from main line service continued to operate the branch lines. NP introduced diesel locomotives to branch operations in 1951. Gray's Harbor diesel operations began in 1952 with the delivery of NP 555-558 in March 1952. NP 558 was located at Centralia, Wash. for road service. In May 1952 N0.558 was wrecked. It required a new nose and cab section. This was usually the Hoquiam-Centralia Local.

Picture 558  at Centralia Wa in October 1955

Engineering 

 

Diagram

Specifications

 

 

The WWSL

The Northern Pacific has a short branch line appearance at Brady, Wash. It is a vignette location, and an operational locomotive is not necessary. I am going to model NP No 558 on my layout in that capacity.

Modeling Information

I am going to kitbatch this locomotive using an Athearn GP9 (actual GP7) Blue Box Edition model.   

 

Process

To be determined

 

Notes:

1. Carbody. The "standard" GP7. Non-dynamic brake equipped, no steam boiler. Solid skirts. Four slots were cut in circa 1955, with  two additional ones added in later years. Cab Windows: Delivered with awnings.

 

2. Full-length 2,200 gallon fuel tanks requiring roof mounted air reservoirs. Winterization hatch. Steam locomotive swing bell intially mounted on right side below the frame and in front of the front truck. Relocated fall 1955 to the short hood. 

 

3. Multi-Unit controls. Single round receptacles were mounted on round posts, just outboard of the center handrail stanchions, almost handrail high. All had the sloping sheets on the foot boards.
 

4. Paint and Lettering: Painted in 'canoe' scheme with 'N.P.R.' and number on cab initially; circa 1955 modified to 'Northern Pacific' on long hood, Monad and number on cab
 

DETAILING PARTS LIST

Virtually all of the needed detailing parts are now commercially available, so generally only one major part per group need be "scratched: "plows, "torpedo" air tanks, extended fuel tanks, and the like. 

Cal-Scale    

• BE-317    Steam Loco Bell   

Detail Associates    

• DS-1401    Drop Step, Early
• LR-1101    Lift Rings, Carbody
• LR-1103    Lift Rings, Pilot/End Plate 
• LT-1004    Headlight, Pyle, Early
• MU-1502    MU Stand (dynamic)
  
• MU-1507    MU Receptacles, Assorted
  
• MU-1508    Pneumatic MU Hoses
• SY-2201    Grab Irons & Bolts

Details West   

• HB-132    Handbrake

Kemtron

• 657    Lift Rings (Cutting Lever)   
• 658    Lift Rings, Carbody
• 788    Handrail Stanchions

Utah Pacific    

• AR-79    Cab Armrest, 2-Bracket   
• AR -80    Cab Armrest, 3-Bracket   
• RM-77    Mirrors (convert to "windwings" by removing centers)   

An Athearn GP7 body, frame, and trucks will be needed as well as paint, decals, light bulbs, jewels, wire, etc.

Paint

Reference

For a more complete account of these locomotives on the Northern Pacific, see Vol. 8 No. 2, Spring 1989 of The Mainstreeter ''The Northern Pacific's GP7 Road-Switchers'' by Bruce Butler, pp. 5-19.

Northern Pacific Diesel Era, 1945-1970 by Lorenz P. Schrenk and Robert L. Frey. Golden West Books, 1988.

Northern Pacific Railway Company, Office Of General Mechanical Superintendent, Distribution Op Power, September 1, 1955

Richard E. Buike, Northern Pacific GP7 Diesel Locomotives 1950 -1970, Prototype Modeler, June 1978

NP Research Library, Diesel Locomotive Roster

NP Research Library, NP Equipment Diagrams,