Method for reaming hole and improved reamer

Abstract

A method for reaming a hole in a metal substrate that minimizes the tendency of long and stringy metal chips to be formed that can surround the reamer with a “steel wool-like” mesh or mass of material, as well as an improved reamer for carrying out this method. The reaming method involves longitudinally advancing the chamfered end of the reamer into the hole at an increased rate of at least about 5 mils (0.13 mm) per cutting edge as the hole is reamed during rotation of the reamer. For holes or bores having a length (L) that is at least about 3 times the cutting diameter (D) of the reamer, a preferred subsequent step is to momentarily reduce the rate of advance of the chamfered end into the hole to about 1 mil (0.025 mm) or less per cutting edge for from about 1 to about 5 rotations of the reamer. The improved reamer has a body, at least three flutes formed in the body, each flute terminating at a chamfered leading end and having a chamfer face proximate the chamfered end, the chamfer face having a chamfer angle of from about 20 to about 30° and having a leading edge of the margin that trails the rake face of the flute, i.e., a negative radial rake angle.

Dependencies are inferred from the claim text.