In 1938, Ralph Hull founded a mill in the rural Oregon Coast Mountains. Lacking enough current to even light the workshop, Hull used steam power to supplement his energy needs. And today the mill still does — as the last steam-powered commercial sawmill on the continent.
Hull-Oakes Lumber cuts about 18 million board feet (43,000 cubic metres) of Douglas fir a year and specialises in cutting big logs, which often clock in at more than 1.8m in diameter and 26m in length. These expansive timbers are often used in the construction of railroad trestles, ship masts and historic building restorations. The mill is itself actually listed on the National Register of Historic Places.
It operates like most saw mills. Freshly-cut timber is dumped into a sorting pond where they are queued for processing by a “pond monkey” (see the debarker reference image) and, as they enter the mill, each log is debarked. Once shorn, it moves up a conveyor system log table, which moves the logs individually down a short ramp to the log turner. The log turner muscles these 24m+ logs onto a carriage and rolls it in place to minimise the amount wasted during cutting. Once the log is in position, the sawyer shuttles the log back and forth past the 2.7m diameter headrig (what houses and drives the saw blade) using a cable-and-pulley system while the the ratchet setter controls the cutting width of each cant (cut section of wood). From there, cants are shuffled over to an edger, where the rough cuts from the band saw are smoothed, and the trimmer, which cuts them to length, before being shipped.
What sets the Hull-Oaks mill apart is that the entire cutting process is powered by two steam engines. The primary engine is a 1906 Ames twin-cylinder (16-inch apiece) with an 18-inch stroke; it powers the band saw and edger. The other engine is used to power the carriage. Wood waste, from the flotsam in the log pond to the sawdust and wood chips from the workshop floor are recycled, fed back to the black, cast iron boilers. Every night at midnight, the boilers are turned on to build a good head of steam for the coming shift. The steam is piped to a steam engine under the mill that converts the thermal energy to kinetic, spinning a flat belt pulley to power the cutting — well, for two hours. Hull-Oaks goes through so much lumber that the blade must be removed for sharpening every 120 minutes.
[This is Carpentry, Armstrong Blue, Library of Congress]
Monster Machines is all about the most exceptional machines in the world, from massive gadgets of destruction to tiny machines of precision, and everything in between.