Tool Forces and Chip Types In Orthogonal Cutting Of Southern Hardwoods

Abstract

Specimens (l/8 to l/4 inch thick) from 5 trees of each of 22 hardwood species were cut orthogonally at 5 inches per minute. Average parallel and normal cutting forces for various rake angles (50, 60, and 70 degrees for veneer; 10, 20, and 30 degrees for planing; 20, 30, and 40 degrees for crosscutting) were measured at three moisture contents (10 percent, 20 percent, and saturated) and four depths of cut .015, .030, .045, and .060 inch). Average parallel forces generally increased with deeper cuts and greater specific gravity but decreased with greater rake angle and moisture content. Average normal forces increased with deeper cuts but were unrelated to specific gravity, moisture content, or rake angle when cuts were in the veneer direction. In the crosscutting and planing directions, average normal forces decreased algebraically with increasing rake angle and changed from positive to negative between 20 and 30 degrees, decreased with increasing moisture content, and increased in magnitude with increasing specific gravity. The general conclusions about chip types that follow are the result of observations made throughout the study.

Citation

Woodson, G.E. 1979. Tool Forces and Chip Types In Orthogonal Cutting Of Southern Hardwoods. Res. Pap. SO-146. New Orleans, LA: U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station. 83 p.