New Developments in Machining Aluminum and Its Alloys 300040
COMPARATIVELY large rake and clear angles required for best results leave a relatively thin cutting-edge on a cutting tool for aluminum. One difficulty encountered is that tools of such form are not always available or suitable, for various reasons, for instance, small tools of various types are available only with cutting edges suitable for steel and bronze, and the desirable amount of top rake cannot well be provided on circular form-tools.
Tool bits of various sorts can be reground to the desired angle. A simple round form of tip that is shown can be utilized in tools for various purposes, including use as inserted teeth in a face-milling cutter. High-speed-steel tools are suitable for most aluminum alloys, but alloys containing a high percentage of silicon can be machined to advantage only by using cemented tungsten-carbide.
Machine-tools should be suitable for high speed. Rigidity is required and lost motion must be prevented to guard against a tendency for the thin points of the tools to dig into the work.
Some experienced machinists find it hard to mentally adapt themselves to the tool form and speeds that are suitable for working aluminum.
A bibliography containing references to a number of articles on the subject that have appeared in American and foreign trade papers, books and house organs, is appended.