Center Drill, Plain, High Speed Steel, 90 Degrees , #9 High-speed steel center drills provide good wear resistance in a wide range of machining applications. Center drills with a plain tip are the standard choice for creating center holes in a piece of stock to prepare it for turning between centers on a lathe.Center drills consist of a pilot drill and a countersink. They are used to create holes at the center of a piece of stock so it can be turned between centers on a lathe in metalworking applications. The pilot drill creates a small hole in the stock and the countersink expands the hole, leaving a small gap at the bottom of the hole that helps protect the lathe's centers from damage when the stock is turned on it.
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