STEAM DONKEY

IN 1:8 SCALE

By B Venables

With the advent of steam power, the logging industry benefitted greatly from the use of steam locomotives, especially the geared type. These were the ‘work horses’ of the woods, hauling Iogs from deep within the forests to the mills. Getting the logs down to the rail head still required teams of oxen, mules, and horses to snake logs down hills and gullies (and sometimes uphill).

It was only a matter of time before steam powered capstans were developed to do most of the work that was done by the animals. Most noticeable of these was the little machine known as the Dolbeer steam donkey engine, circa 1882. The Dolbeer was very basic at first with a single cylinder engine driving a wheel capstan or gypsy head. A cable or lead line could be pulled in by the capstan but then the heavy cable had to be hauled back into the woods by a horse. Within a short time, Dolbeer added a small haulback drum and the horse was no longer required for the haulback operation.

In the mid 1880s, a number of improved steam donkey engines were available. Some of the more notable ‘donkeys’ were produced by the American Hoist and Derrick Company, of St. Paul, Minnesota, Washington Iron Works, Seattle, Washington, and Willamette Iron and Steel Company of Portland, Oregon. The improved, more efficient donkey engines had two-cylinder engines, larger boilers, two horizontal drums with massive brakes and friction clutches.

The first drum was used for the main line and the second drum was used for the haulback line. A horizontal drum machine was a great improvement over the vertical capstan or gypsy head in that the main line was hauled and reeled up on the drum. A capstan requires a cable handler to take a number of turns of cable on the head and keep tension on the cable. At the same time, he had to coil the cable loosely on the ground.

Steam donkey engines were used in the United States well into the 1930s when steam was being replaced by internal combustion engines. I well remember the many uses of steam donkey engines before their demise. At most large building sites, the steam donkey engine showed its versatility by first being fitted to a pile driver frame and driving foundation piles. The piles were hauled by choker cable into position beneath the pile driver head. One cable drum was used for this operation. The second cable drum was used to raise and lower the driver head. Steam for the pile driver was taken off the boiler steam manifold through a long flexible hose to the driver head.

The head was simply a massive cast iron hammer raised by a single-acting steam cylinder with a trip valve that exhausted the steam at the top of its stroke, thus allowing the hammer to drop. After all piles were driven, the steam donkey would pull itself off the pile driver base frame and the crew would position it for hoisting duty. The steam donkey would lift all the steel for the steel frame of the building and then, in tum, all the other heavy building materials. A spar pole with a boom would be raised from one floor to the next, but the donkey hoisting engine would always remain at ground level.

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