Roots of Motive Power
The Roots Collection
1928 Washington Iron Works
Estep Diesel Yarder
C/N 4055 Built April 4, 1928 10" Bore, 12 1/2" Stroke

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From the Roots of Motive Power Newsletter, August 2004:
The dark smudges lingering on the ceiling of the Roots Restoration Facility just above the stacks of our Washington Iron Works Estep Yarder bear evidence that Vrain Conley and crew (Percy Daniels, Keith Rongey, Mike Wade, Ed Vikart, Harry Pond, Bert Bertolini and others) have made significant progress in their restoration efforts. Friday, May 28th, 2004 was the day the Estep first rumbled, if a bit uncertainly, to life; flames erupted from some cylinders, black oily soot from others, but the sound of the engine was unmistakably Estep. Having helped to arrange the donation of the Estep from Simpson Timber Company in Shelton, Washington in 1992 and the transport back to Willits, it is a tremendously rewarding feeling personally to see this rarest of artifacts close to operation. Work continues on fine tuning the injectors and fuel system, but the Roots membership should soon be able to enjoy the extraordinary spectacle of the only complete Washington Estep Yarder in existence in operation.

by Chris Baldo


From the Roots of Motive Power Newsletter, April 2002:
The year 1992 was a banner year for acquisitions to the Roots collection. One of the more interesting was the Washington Iron works Estep Diesel Yarder which was donated to Roots of Motive Power by the Simpson Timber Company of Shelton, Washington. We started our discussions with Simpson regarding the yarder in 1989 and final approval for the donation was in early 1992. The following story was from the Roots Newsletter ten years ago, after the arrival of the Estep in Willits.

Our Washington Iron Works Estep diesel yarder is now at home on the rail spur at the Museum in Willits. Built in 1928, the Estep diesel yarder signaled the beginning of the end for the steam donkeys that had filled the woods with their whistles since the mid-1880s. Only 35 were built, before the great depression hit the country and the timber industry, by Washington Iron Works of Seattle, which built thousands of steam machines. The list of purchasers of Estep diesel yarders reads like a who's who in the timber industry: redwood operations such as Southern Redwood Corporation at Rockport in Mendocino County, Northern Redwood Lumber Company (later to become part of Simpson's California operations), The Pacific Lumber Company, and other industry leaders such as Weyerhaeuser Timber Company, Long-Bell Lumber Company, Simpson Logging Company, Coos Bay Lumber company, Crown Willamette Paper Company, and Merrill and Ring Lumber Company. The huge Estep diesel produced only 200 HP and was replaced at the depression's end by more powerful, compact diesel engines.

Simpson Timber Company's logging operations span a hundred year period in the heavily timbered hills west and north of Shelton, Washington on the Olympic Peninsula. Names like Skokomish, Lake Nahwatzel, Wynoochee make it seem that the region was named out of a Chinook Indian dictionary. Old growth timber extended northward to the snow-capped peaks of the Olympic mountains. As the loggers struggled north from Shelton, the finest second growth forests in the world established in their wake and provided Simpson Timber Company wood products on a sustained basis. The Estep worked in Simpson Logging Company Camps 1 and 2 on the East Fork of the Satsop River after being purchased in 1928. It moved to Camp 3 on the Skokomish River in 1930 when timber was exhausted and both Camps 1 and 2 moved north. In 1949, the yarder was moved to the shops in Shelton where a third drum was added to the frame for use in its new life as a loading machine. Moved to the Canyon River Transfer, the rebuilt machine was used until the early 1960s to transfer logging truck loads to rail cars for transport on the Simpson railroad to Shelton. The Estep survived another 30 years of the constant threat of being sold for scrap metal through the brilliant efforts of unnamed Simpson Employees who maintained that the yarder be used as a tail hold for the new reload machine.

The Washington Iron Works Estep diesel yarder was an engineering masterpiece for its day. The 200 HP, 6 cylinder engine had 10" diameter pistons with a 12 ½" stroke and turned an easy 300 RMP. All yarder bearings are tapered Timken roller bearings; controls are air operated with Berger variable pressure regulating valves, and four different gear changes are possible. It weighed 81,000 pounds and had a line pull of 150,000 pounds. Washington Iron Works built the Estep diesel engine for many applications other than logging. Several are still in use in the maritime industry in tugboats and other vessels.

The Estep Yarder is mounted on a Pacific Car and Foundry skidder car, a railroad flatcar specifically designed for moving donkeys in the woods. This car is built with 360 degree swiveling trucks that permit it to be turned end for end at a switch on the landing in the woods. This particular car, Simpson Logging Company No. 1, was built in 1918 for the U. S. Army Spruce Division that worked in the Pacific Northwest during World War I to produce spruce for airplane construction. The car was sold to Willamette Iron and Steel in Portland after the war as surplus along with other Spruce Division machinery. Willamette Iron and Steel, a major manufacturer of steam logging machinery, sold the car with a new steam donkey attached to Simpson Logging Company in the early 1920s. The rail car joins other railroad logging equipment in the Roots collection, including Holmes Eureka #4, a two truck Climax locomotive, California Western #14, a 2-6-2T Baldwin, disconnected logging cars from Mendocino Lumber Company and Caspar Lumber Company, and a Union Lumber Company caboose.

Four Roots of Motive Power volunteers, Richard Burger, Gene Roediger, Dorothy Roediger and Chris Baldo, ventured up to Washington in early September, 1992 to prepare the machine for loading and assist the Simpson crews during the loading operation. The yarder was unloaded at the Mendocino County Museum yard with the help of a heavy crane donated by Bill Daniel of Daniel Iron and Steel of Ukiah. In making the acquisition, documentation, and move of the yarder possible, Roots of Motive Power gave thanks to the following individuals: Bruce Coombs, Frank Brehmeyer and Mike Smith of Simpson Timber Company; Ed Rush of Rushway Trucking; John Taubeneck, Bill Petitjean, Pete Replinger, Bill Daniel, Susan Huner, Ed Olenik and Dan Taylor.