Fore-and-aft plank road with wedges on cross ties to facilitate the re-aligning of the planks.
With a good road of this type and a bearing surface of thirty inches, the trouble and expense of a guard rail may be eliminated. When a light truck is used for a small body of timber such a wide and heavily constructed road is not practical. In this case, a four inch plank with a fifteen inch surface and an eight inch pole for a guard rail would be used. Here again the track must be made wider on the sharp curves, often as wide as three and a half feet. Usually, the inner rail is made wider than the outer one. On very sharp curves the track may have to be planked solid to keep the trailer from running off. By sawing out chips from one-half to one inch wide two-thirds of the way through the plank, and about six feet apart on the inner side, a long plank may be bent around quite a sharp curve. The ties, of course, should be placed so as to allow the cut sections of the plank to rest squarely on them. This does away with the short pieces and so strengthens the track.
The company logging at Camano Island, Washington, operates over a road of this type, an [illustration] of which is shown on page 38. The difficulties encountered in the construction of this particular road were very considerable as a cut through very hard shale, in some places as much as seven feet, was necessary. The maintenance on this road is heavier than is usual. Two men are employed to work on it continually. The work consists of blocking up the loose ties and plank, making any necessary repairs and keeping sand and gravel on the steep grades. The cost of this work is good insurance as it keeps the road in the best of condition at all times and saves on other operating expenses.
Detailed view of fore-and-aft plank road,
showing method of wedging.
Cost. The first cost of a road of this type is high but it more than pays in the long run if a large body of timber is to be hauled over it. The timber used in its construction amounts to about 160 thousand feet per mile. Second grade material can be used at a cost of approximately $5,500 a mile for the plank. The total cost per mile varies from $6,000 to $8,000. The plank road at Camano Island cost $20,000 for two and three-quarter miles, which includes the cost of the plank, the grading and labor of putting the plank in place. This is at the rate of about $7,275 a mile, or approximately $138 a hundred foot station. The overhead charge for the road at this operation is $.75 a thousand feet of timber hauled over it. Plank roads of lighter construction have been built for $4,000 a mile. The length of life is about the same as that of a pole road, three to four years.
The fore and aft plank road is one of the best roads that can be put in where the timber is of sufficient quantity to justify the expense. The big advantage is the speed that can be made and the saving in the equipment. Such a road is very free from bumps and the jar and vibration on the truck is no greater than on a city pavement. The depreciation on a truck depends to a great extent upon the road operated over. With the above type, depreciation on the truck will not be less than five years. In addition, tire mileage will be double that obtained over a pole road, and the gasoline and repair expense will be very materially cut. Owing to the very small vibration, a load of logs can be brought to the landing as fast as it is safe to let the truck glide on a down grade. Speeds as high as 20 miles an hour can easily be taken without excessive vibration. The traction is greater on this type of road than it is on the pole road, due to the greater bearing surface. Traction on grades up to 12% is easily secured by sanding the plank.
Concrete Roads. Concrete has been suggested as an ideal road material. However, up to the present time, loggers have not been very enthusiastic about this type of road on account of the cost of construction, which is somewhat more expensive than the other types of roads, and on account of the permanence of the finished road which is beyond that needed. To the writer’s knowledge, there is no company operating in the Northwest over a concrete road of their own building. In the future such roads may be used to a limited extent on the main haul by companies which have operations extending over at least a five year period. The spur roads will probably always be of some other material.