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Abstract
A process is described in which a shaping-lathe headrig produces flakes of optimum geometry while rounding 8-foot peeler bolts to their maximum cylindrical diameter. The cylinders are then passed, at a rate of 5 to 7 per minute, to a veneer lathe for production of continuoua veneer, which is subsequently clipped into 4- by 8-foot sheets. Veneer cores are flaked in a separate operation; theee flakes, mixed with the flakes resulting from roundup, veneer residue, and panel trim, are pressed into 4- by 8-foot core sheets 9/32 to 13/32 inch thick. In a separate pressing operation, the flake cores are faced with 1/8-inch veneer to yield structural exterior composite sheathing of superior quality. By this process, a ton of bark-free peeler bolts should yield more than .9 ton of sheathing (OD basis); less than .1 ton (mostly sanderdust) ends as fuel. All other residue, except bark, is incorporated in the sheathing. The propoeed plant will consume 5,000 to 6,000 peeler bolts per 3-shift day. Based on an average log diameter (small end, inside bark) of 10 inches, annual production during 240 3-shift operating days should be 100,000,00 square feet of 17/32-inch panel (1/2-inch nominal). Plant Cost plus operating capital is estimated at $23,000,000. When sited in western Massachusetts or in central Maine, the operation should return a before-tax profit of about 36 percent (and an after tax profit of 18-1/2%) of the entire investment; cash flow should be about 28-1/2percent, or $6,520,000 annually, after taxes.
Citation
Springate, N.; Plough, I.; Koch, P. 1978. Shaping-lathe roundup machine is key to profitable manufacturing of composite sheathing panels in Massachusetts or Maine. Forest Products Journal 28(10):42-46
