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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.



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.

References in periodicals archive ?
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.
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.
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.
All SMART-BIT pre-drilling & countersinking tools are packaged with a hex wrench and two easy-to-change replacement bits available in #7 and #8 trim, as well as #10, #12 and #14 flat sizes.
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.
Tools include a sewing machine, saw, nailset, and an electric drill with a 1/4-inch bit and a long-shanked pilot bit for countersinking the woodscrews (this bit has a 5/16-inch-wide upper flange).
One of the catalog spotlights is machine shop accessories available for the portable magnetic drill models that broaden their work range including, pipe adapter kits, vacuum base adapters, tapping attachments, countersinking tools, twist drill adapters, and Jacobs[R] chucks, ratchet drive feeds, arbor extenders, and spindle adapters.
The orthopedic screw includes a unique radial head design and self-tapping thread complemented by a unique countersinking drill.
You'll need a table saw with dado blades, a router with a round-over bit, and a drill with a bit for countersinking screws.
To build either one requires a table saw, a router (or a set of dado blades for your saw), bar clamps, an electric drill with 1/4-, 3/8-, and 3/4-inch bits, a pilot bit for countersinking #10 woodscrews, and wood glue.