Milwaukee Road EP-3 “Quills”: History, Specs & Roster

Last revised: September 1, 2026

The Milwaukee Road class EP-3 was ten Baldwin–Westinghouse passenger electrics built in 1918–19 for 3,000-volt DC. Railfans call them Quills after the drive, not after the carbody. Each of six driving axles sat inside a 15-inch steel tube. Twin motors bolted to the frame turned that tube; coil-spring “spiders” took the torque to the 68-inch drivers. Unsprung weight was wheels and axles only. Milwaukee numbered them 10300–10309, then E10–E18 in 1939. 10303 was allocated E19 and never wore it. They handled the Olympian and later the Olympian Hiawatha on the Rocky Mountain Division. Interestingly, engineers liked them but the mechanical department did not. Frames, axles, wheels, and springs kept breaking on mountain curvature making them a general maintenance headache. None were rebuilt in the late-1940s electric overhaul and the last two, E11 and E18, were cut up in April 1957. Sadly, this is the only class of Milwaukee electric which was not preserved.

Milwaukee Road Quill E-11 with eastbound Olympian Hiawatha boarding at Missoula Montana circa 1956

Milwaukee Road Quill E-11 with train 16, the eastbound Olympian Hiawatha, boarding at Missoula, Montana, circa 1956. American-Rails.com collection.

On this page: At a glance · Why “Quill” · The USRA split · One boxcab, two Pacifics · Specifications · Frames, axles, and 10301 · Mountain Division · Left out of the rebuild · Roster

At a Glance

Item	Detail
Railroad / class	Chicago, Milwaukee & St. Paul; later Chicago, Milwaukee, St. Paul & Pacific. Class EP-3
Nickname	Quills, from the quill drive
Builders	Baldwin Locomotive Works (mechanical), Westinghouse Electric (electrical). Milwaukee’s only Baldwin–Westinghouse road electrics
Built / in service	December 1918–September 1919 construction; service late 1919 into early 1921
Quantity	10
Original numbers	10300–10309
1939 numbers	E10–E18. E19 allocated to 10303, never applied
Wheel arrangement	AAR 2-C-1+1-C-2; UIC (2′Co1′)(1′Co2′); Whyte analog 4-6-2+2-6-4 OE. Two Pacific-type running gears back-to-back under one cab
Wire	3,000 V DC overhead; two pantographs
Drive	Six twin-armature motors, frame-mounted, geared to 15-inch quills, 24:89
Horsepower	Westinghouse sheet: 4,680 1-hour / 3,396 continuous. Milwaukee 1928 magazine: 4,200 / 3,400
Rated speed	65 mph. Crews regularly ran 70–80 mph
Territory	Rocky Mountain / Missoula Divisions (Harlowton, Mont.–Avery, Idaho). Bipolars took the Coast. Quills were the Montana–Idaho passenger motor
Retired	Two wrecks (1933, 1947); E17 December 1950; remainder 1952–April 1957
Survivor	None

Why they are called Quills

A quill is a hollow shaft around the driving axle. Westinghouse put a 15-inch steel tube through the motor bearings, with the axle free inside it. Seven-armed spiders at each end of the tube reached between the spokes of the driving wheels and connected through coil springs. The motors sat on the locomotive frame, above the roadbed. The only unsprung mass on the rail was the wheelset. Milwaukee’s 1928 magazine described it that way; so did Westinghouse’s 1924 data sheet. The name is the drive. It is not a description of the boxcab.

The same idea later appeared, famously, on the Pennsylvania Railroad GG1. Milwaukee had it in 1919. Electric Railway Journal (March 13, 1920) said the drive was a further development of New Haven practice. New Haven class EP-2s were Baldwin–Westinghouse boxcabs with quills, 1-C-1+1-C-1, about 175 tons. Milwaukee’s EP-3s were heavier, 2-C-1+1-C-2, with a lighter frame on mountain track.

Official schematic of Milwaukee Road class EP-3 Quill electric locomotive

Official schematic of the EP-3 Quills. American-Rails.com collection.

Fifteen passenger motors, two builders

When Milwaukee electrified the Coast Division it wanted more General Electric passenger power. However, the United States Railroad Administration was still running the railroads during World War I and ulimately split the electrical order: of fifteen new passenger locomotives, five would be GE (the EP-2 Bipolars) and ten would be Westinghouse, with Baldwin on the mechanical part. That is the EP-3. A University of Montana thesis on the electrification puts it bluntly: Westinghouse did not have GE’s DC-traction record, and the two firms took the same specification in opposite directions. GE built a gearless bipolar motor on the axle. Westinghouse built a high-driver Pacific-type chassis and a quill.

These are Milwaukee’s only Baldwin–Westinghouse road electrics. The ES-1 / ES-2 switchers were GE.

One carbody, two Pacific running gears

Westinghouse’s 1924 sheet is the clean description: two Pacific-type running gears coupled back-to-back, supporting a single cab that held the control and auxiliaries. Wheel arrangement 2-C-1+1-C-2. Twelve 68-inch drivers. Four 36-inch idlers. The locomotive is double-ended as built. It is not two semi-permanently coupled Alco boxcab halves the way an EF-1 is. The EP-3 is one long carbody. Loco-info notes that because the body was not split, the chassis layout had to do more work. That is exactly where the class failed.

Six twin-armature motors, Westinghouse type 348 on the 1927 builder folder. Each armature wound for 750 volts, twins in series for 1,500 volts per motor, motors insulated to run two in series on 3,000-volt trolley. Gerald F. Smith’s 1918 Electrical Journal paper on the contract motors: 667 hp one-hour per motor (covers off), 533 hp continuous. Six of those is about 4,000 / 3,200 hp. Later sheets quote 4,680 one-hour and 3,396 continuous for the locomotive; Milwaukee’s 1928 magazine used 4,200 / 3,400. Finally, an oil-fired steam generator was utilized for train heat while it was equipped with a motor-generator and battery for auxiliaries. Lastly, regenerative braking was also equipped on the fleet.

Milwaukee Road EP-3 Quill E-12 ahead of the Olympian Hiawatha at Butte, Montana, September 4, 1950. Photographer unknown.

Second view of Milwaukee Road Quill E-12 and Olympian Hiawatha at Butte Montana September 4 1950

The same train at Butte, September 4, 1950.

Specifications

Builder figures below are the 1924 Westinghouse data sheet and the 1927 Baldwin–Westinghouse folder (road numbers 10300–10309, 88 ft 7 in, 600,000 lb). Milwaukee’s 1928 magazine and the 1941 Trains electrification article quote 620,000 lb total and 420,000 on drivers. Early contract papers also used 266 tons (532,000 lb) while the machines were still on the drawing board.

Specification	Value
Builders	Baldwin (mechanical), Westinghouse (electrical)
Years built	December 1918 (10300) through September 1919 (10307–10309). Placed in service 1919–early 1921; builder publicity often says 1920
Wheel arrangement	2-C-1+1-C-2 (AAR); (2′Co1′)(1′Co2′) (UIC); 4-6-2+2-6-4 OE
Electrical system	3,000 V DC overhead; two pantographs
Traction motors	Six Westinghouse twin-armature (type 348 on the 1927 folder), frame-mounted, one above each driving axle
Drive	Single-reduction gearing to a 15-inch quill; spiders and coil springs to the drivers. Gear ratio 24:89
1-hour rating	4,680 hp (Westinghouse 1924 / 1927). Milwaukee 1928: 4,200 hp. 1918 contract paper: 4,000 hp
Continuous rating	3,396 hp (six × 566). Milwaukee 1928: 3,400 hp. 1918 contract: 3,200 hp
Starting tractive effort	105,000 lbf at 25% adhesion (Milwaukee 1928 and later sheets)
1-hour tractive effort	66,000 lbf at about 26–27 mph (Westinghouse / Milwaukee 1928)
Continuous tractive effort	49,000 lbf at 26 mph (Milwaukee 1928); Westinghouse 1924 also lists 40,800 lbf continuous
Rated maximum speed	65 mph. In service, 70–80 mph was ordinary on favorable track
Driving-wheel diameter	68 in (builder). Milwaukee 1928 table also prints 69 in
Idler-wheel diameter	36 in
Length over coupler faces	88 ft 7 in
Total wheelbase	79 ft 10 in
Rigid wheelbase	16 ft 9 in
Height	14 ft 6 in (Wikipedia / later tables). 1927 folder also lists 17 ft 0 in over pantograph
Total weight	600,000 lb (builder). Milwaukee 1928 / 1941: 620,000 lb (300 tons in running text)
Weight on drivers	378,000 lb (Westinghouse 1924; ~63,000 per driving axle). Milwaukee 1928: 420,000 lb (70%)
Train heat	Oil-fired steam generator
Control	Westinghouse electro-pneumatic HBF (1927 folder)

Too light, too rigid, and the 10301 experiment

Crews liked them from the first winter. They did not slip like the 1915 boxcabs. They rode smoother than the Bipolars. They would walk a heavy Olympian and still run 70–80 mph when the profile allowed. Within a year the shop had a different story: broken axles, cracked frames, cracked wheels and spokes, sprung suspension coils. Too little lateral play in the drivers chewed flanges on mountain curves. The 68-inch wheels, a steam-Pacific size, put the stresses high. Westinghouse had designed a New Haven-weight idea onto a heavier locomotive and a twisting 2 percent railroad.

Meetings in 1922 tried to fix it. Baldwin wanted the carbody cut in two, making a permanently coupled two-unit boxcab. Reinier Beeuwkes’s Electrification Department did not. Only 10301 was split. It did not help. Milwaukee converted it back to a single body. A second locomotive was rebuilt to Milwaukee’s own prescription: heavier frame steel, Commonwealth Delta idler trucks to steer into curves, and the class converted toward single-end operation. That package went onto the rest of the fleet. It was better. It was not a cure. Holley and the class histories count about five rebuild campaigns over the life of the engines.

Milwaukee Road class EP-3 Quill E-11 with the Olympian Hiawatha near Butte Montana circa 1956

Milwaukee Road class EP-3 Quill E-11 with the Olympian Hiawatha under the wires near Butte, Montana, circa 1956. American-Rails.com collection.

Harlowton to Avery, not the Cascades

The 1927 Olympian booklet is explicit. The Westinghouse geared-quill type “operates across Montana and Idaho.” The GE bipolar “operates across the Cascades.” Quills were the Rocky Mountain / Missoula Division passenger motor: Harlowton to Avery, Pipestone, Vendome Loop, the Bitterroots. After 1919 the original EP-1 boxcabs went to freight; the Quills took the varnish on the mountain.

They could handle a 950-ton train (about twelve coaches) over the 440-mile mountain run, including 21 miles averaging 1.72 percent with a 2 percent maximum, at schedule speed. Starting effort 105,000 lbf. Continuous 49,000 lbf at 26 mph. President Warren G. Harding sat in the cab of 10305 in 1923 on the western trip that ended in San Francisco. The live filename on that photograph is QuillE16.jpg featured below. The locomotive is 10305 (later E14).

They derailed more than the railroad liked, and 300 tons made a derailment worse. 10303 was wrecked in January 1933, stored, and scrapped in September 1942 without ever wearing E19. 10304, by then E13, was wrecked at Soudan, Montana, and scrapped in July 1947.

U.S. President Warren G. Harding in the cab of Milwaukee Road EP-3 Quill 10305, circa 1923. The file on this site is named QuillE16.jpg; the locomotive is 10305, later E14.

Skipped in the rebuild, gone by April 1957

After World War II the electrification shop laid out a program to keep the mountain motors going. Little Joes arrived in 1950 for freight. The Bipolars got the 1953 rebuild. The boxcabs were re-geared and combined into EF-2 / EF-3 / EF-5 sets. The Quills were left out. They were the headache. E17 went in December 1950. The rest of the seven still on the property were retired from 1952 through April 1957. E11 (the 10301 that had been cut in two and put back) and E18 were the last, scrapped April 1957.

Nothing was saved. There is no Quill in a museum. The boxcab E50 at Duluth, Bipolar E2 at St. Louis, and Little Joe E70 at Deer Lodge are the Milwaukee electrics you can still stand next to. The EP-3s today live on in photographs and schematics.

Roster

Build months and Baldwin serials follow Edson / Diesel Shop. 10303 was assigned E19 in the 1939 scheme and was already wrecked; the number was never painted on.

First no.	1939 no.	Baldwin serial	Built	Disposition
10300	E10	51000	Dec. 1918	Scrapped May 1955
10301	E11	51844	June 1919	Split-body experiment, converted back. Scrapped April 1957
10302	E12	51845	June 1919	Scrapped May 1954
10303	E19 allocated, never applied	52111	Aug. 1919	Wrecked January 1933; stored; scrapped September 1942
10304	E13	52170	Aug. 1919	Wrecked, Soudan, Mont.; scrapped July 1947
10305	E14	52215	Aug. 1919	Harding cab photograph, 1923. Scrapped September 1952
10306	E15	52239	Aug. 1919	Scrapped May 1955
10307	E16	52302	Sept. 1919	Scrapped May 1955
10308	E17	52347	Sept. 1919	Scrapped December 1950
10309	E18	52362	Sept. 1919	Scrapped April 1957

Sources

Gerald F. Smith, “The Twin Armature Motors for the Chicago, Milwaukee & St. Paul Direct-Current Locomotives,” Electrical Journal, October 1918 (Sol): 667 / 533 hp per motor, quill, Rocky Mountain assignment
“The New Passenger Locomotives,” Electrical Journal, February 1918 (Sol): 4,000 / 3,200 hp contract ratings, 950-ton train
Batchelder, Dodd, and Storer, “Two Designs for Passenger Locomotives,” Electric Railway Journal, March 13, 1920 (Sol): New Haven quill lineage, 4,200 hp, control combinations
Westinghouse Railroad Data, 1924 (Sol): 600,000 / 378,000 lb, 4,680 hp 1-hour, 68-in drivers, 24:89, 950-ton / 440-mile run
Baldwin–Westinghouse folder 4756, 1927 (Sol): 88 ft 7 in, 600,000 lb, type 348 twins, 4,680 hp, in service 1920
“The Giant Electric Locomotive,” Milwaukee Road Olympian booklet, 1927 (Sol): quills on Montana–Idaho, bipolars on the Cascades
Milwaukee Road Magazine, August and September 1928 (Sol): 300 tons, 105,000 / 49,000 lbf, 4,200 / 3,400 hp, Rocky Mountain and Missoula Divisions
“Milwaukee Electrification,” Trains, July 1941 (Sol): 620,000 / 420,000 lb, 4,200 hp hourly
Noel T. Holley, The Milwaukee Electrics (Hundman, 1999)
William D. Middleton, When the Steam Railroads Electrified (Kalmbach, 1974)
Paul T. Warner, “Locomotives of the Milwaukee Road,” Pacific Railway Journal 2, no. 6 (June 1958)
William D. Edson, “Milwaukee Road Locomotives,” Railroad History 136 (Spring 1977)
The Diesel Shop, Milwaukee Road electric motors (Baldwin serials 51000, 51844–51845, 52111, 52170, 52215, 52239, 52302, 52347, 52362)
Michael Sol, Milwaukee Road Archives