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Related to Countersinking: spot facing, trepanning


(mechanical engineering)
Drilling operation to form a flaring depression around the rim of a hole.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



a method of working (finishing) conical surfaces (bevel edges or chamfers) of center holes in parts prior to center adjustment for further finishing or before assembly. In single-unit and small-series production countersinking is performed on drilling machines, and in large-series and mass production it is done on centering machines with center-bit drills and countersinks.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
In particular, efforts were concentrated to quantify expansion and retraction phenomena in countersinking process by analyzing the evolution of hole diameter, sheet thickness near countersink and diameter of workpiece.
While the manual countersinking tool previously-used lasted a day or two, the E-Z Burr carbide insert ran for a month before Skyway had to replace it.
Further details on Starborn's other internationally recognized products are also available: Headcote[R] Stainless Steel Screws with Color Coated Heads (, Smart-Bit[R] Pre-drilling and Countersinking Tool (, Smart-Bit[R] Pro Plug[R] System for Wood (, and Cap-Tor[R] Screws for Capstock and Composite Decking (
Edison, NJ, January 07, 2011 --( Starborn Industries, Inc., a leading manufacturer of fasteners and related products for the building industry, has expanded on its domestic and international sales success of its SMART-BIT[R] pre-drilling & countersinking tool with the receipt of patents in both Australia and Canada.
Countersinking bugle head screws so they are flush or slightly recessed leaves a neat appearance.
The new end mills are multipurpose tools for drilling, milling, spotting, chamfering, and countersinking, and offer optional AlTiN coating.
Tape measure Combination square Framing square Handsaw Circular or table saw Electric drill 3/8-inch countersinking bit 3/8-inch plug cutter Chisel Wire brush Dust mask Paintbrush Notched trowel for mortar Rubber mallet Hammer
announces its new Cham-Bit, specifically designed to simplify the process of countersinking, chamfering, or de-burring small holes while drilling.
has introduced the Felix 2010, an all-in-one tool for interpolating, ramping, chamfering, countersinking and finishing.
With the boards carefully positioned and spaced, drill through all the marked points with a countersinking bit sized for #10 flathead woodscrews so the screw will be recessed about 3/8 inch.
Tooling solutions for deburring, chamfering, and countersinking holes will be exhibited by Cogsdill Tool Products at Westec 2004.
The center thread mill is used for countersinking and threading in one pass.