countersink

[′kau̇nt·ər‚siŋk]

(design engineering)

The tapered and relieved cutting portion in a twist drill, situated between the pilot drill and the body.

countersink

countersink

A boring bit having a conical-shaped cutter; used to make a depression to receive the head of a screw or bolt so that it does not protrude above the surface.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Countersink

(Russian, zenkovka; from German senken, “to sink, lower”), a cutting tool used for countersinking. Countersinks usually form part of a set with centering drills. The sizes of countersinks in each set depend on the diameter of the hole; in all sets, the vertex angle is 60°. Coun tersinks are made for chamfering center holes with diameters of 0.5 to 1.5 mm (ordinary countersinks), for holes with diameters of 0.5 to 6 mm (with or without protective taper), and for holes with diameters of 8 to 12 mm (with tapered stem). Countersink cutting elements are made from high-speed steel; countersinks with tapered stems are welded and the stems are made from carbon structural steel.

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References in periodicals archive

Pilot holes reduce the risk of splitting boards and allow you to get tighter-fitting, better-looking joints (especially if you use a countersink bit).

They all drove easily with no stripping or breakage and sat perfectly flush without the need for a countersink bit. We also observed no splitting when driving them near the ends of the boards.

25 tips for driving screws

Fasten with four screws per side, predrilling all the holes with a countersink bit to avoid splitting the wood.

Barbecue cart: a serving table and a home for your grilling gear--in one day!

Tools Smoothing plane Portable circular saw Tape measure and straight edge Combination square and pencil Coping saw (or electric jigsaw) Hammer Spoke shaves: round-bottom and flat-bottom Electric drill Drill bits: 2mm, 3mm, 5mm, countersink bits Utility knife and scissors Cork sanding block or electric sander Screwdriver (cross-headed or slotted) Here's how: Preparing the boards 1.

Toy Box on Castors

Countersink bits for the drill are always recommended so the fiberglass doesn't fracture.

Good day sunshine: add a solar trickle charger and keep your battery happy

* Countersink bits widen holes so flathead screws may be flush mounted below the surface for a finished appearance.

Drilling tools

Tools required: Sandbug electric sander; Gofer X ultra compact rechargeable screwdriver; Pincers; Pencil; Power drill with twist and countersink bits and a knife

Forget the fellas

With a set of countersink bits like these, you can complete both operations in one step.

Driving screws: for such a simple task, it's surprising how many things can go wrong when you drive screws. stripped screw heads, split board ends and broken screws are just a few common problems. we'll show you how you can avoid all the frustration just by using the right screws and a few special tools

I say "nearly" because I have had to tuck a few extra items into it, like a bit extender, a set of pilot countersink bits and some Vix bits, so I end up with a 97-piece set instead of a 90-piece set: I'd say Ryobi pretty much hit it on the head when putting this set together.

David's drill kit

Countersink bits are available with or without stop collars.

Driving screws: with the right techniques, screws will go in easier, and you'll stop stripping out screw heads