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How to use a countersink drill bit so the head sits flush

Updated: 2026-10-23

A proud screw head on a cabinet door is usually a depth problem, not a mysterious bit. You set the stop too deep, the pilot walks because the grub screw was barely nipped, or you countersink a hole that was never the right size. This is how to use a countersink drill bit on a cordless drill at home: shallow first, locked second, proved on scrap with the same screw before you touch the job. The sets themselves are in the [countersink drill bit comparison](/hub/drilling-and-accessories/countersink-drill-bit). Products Compared read amazon.co.uk listings on 19 October 2026 and public UK workshop notes. We did not run a lab test. A qualifying purchase can earn a commission at no extra cost to you.

A proud screw head on a cabinet door is usually a depth problem, not a mysterious bit.

Our top picks

DECKRKAT DECKRKAT 8-piece countersink set

Best overall

DECKRKAT DECKRKAT 8-piece countersink set
7.7/10about £18.98
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Makita Makita D-73455 4-piece countersink set

Best value

Makita Makita D-73455 4-piece countersink set
7.5/10about £7.92
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EZARC EZARC 12-piece countersink set

Rank 3

EZARC EZARC 12-piece countersink set
9.0/10about £17.99
View offer
On this page
  1. 1.One pass or two
  2. 2.Set the stop and tighten the clamp
  3. 3.The test hole
  4. 4.When to stop

One pass or two

A combined hex bit drills the pilot and the cone together: a small drill in the countersink body, a 1/4 inch or 6 mm shank, and a stop. The clearance hole, in the piece that must pull down, is about the outside of the thread. If you only own the combined bit, you still need that clearance hole when two boards clamp together. A plain chamfer is the second operation only. Torveen and Kaquxibix, the 12 mm, 16 mm and 19 mm bits, do not drill a pilot. You make the hole with a twist bit, then bring the cone in. Do not use that method for ATOPLEE. That listing says hand drills are not allowed and the bits are not for opening holes.

Set the stop and tighten the clamp

Set the stop shallower than the head you want. Loosen the grub screw, slide the body so only a short cone will cut, and tighten the hex key until the screw bites. Deepen by a turn only if the head stands proud. Starting deep leaves a crater you cannot put back, especially in veneered board. A loose setscrew lets the countersink body spin on the pilot. One DECKRKAT review stripped the grub screw on the first holes and drove the bit into plywood. EZARC reviews include collars that will not stay tight and, on the 15-piece, a missing Allen key. Tighten the key you were given. If the pilot slips out of the body, stop. On a thin piece, drive the screw by hand for the last turn so the clutch does not pull the head through.
DECKRKAT DECKRKAT 8-piece countersink set

Testsieger

DECKRKAT DECKRKAT 8-piece countersink set
7.7/10about £18.98
View offer

The test hole

Clamp the work, or clamp a scrap of the same board. Wear eye protection. Chips from a HSS cone are small and sharp. Start slow, and keep the drill square. Drill the scrap, then drive one of the screws you will actually use. A head that stands proud needs a slightly deeper stop. A head that drops below the surface was already too deep. A head that touches only on a bright ring is often an angle mismatch. That case goes to the 82 or 90 degree countersink page. A split at the edge of a narrow rail goes to the countersink drill bit for wood page.

When to stop

Stop when the fixing is structural, when the screw is in a fire door, or when someone has specified a countersunk fastener as a loaded joint. BS EN ISO 10642's point about reduced loadability is a fastener limit, not something you correct with a deeper cone. Steel, tile, concrete and masonry are outside the wood sets. If the hole is in a joist hanger or a calculated stair stringer, a joiner should take over. Buying a different brand from the same twelve will not change that.

Common questions

Do I drill the pilot first or use the combined bit in one pass?
Use the combined bit in one pass when it includes a pilot of the right diameter and the top piece does not also need a larger clearance hole. When two parts must pull together, drill clearance in the first piece, then the pilot in the second, then the countersink. Chamfer-only bits such as the 12 mm Torveen and Kaquxibix cutters need a hole first. They never drill the pilot for you.
How do I set the depth stop?
Loosen the grub screw, slide the collar or the countersink body so the cone will cut less than the head height, and tighten the hex key hard. Drill scrap, seat one real screw, and only then deepen the stop if the head stands proud. A stop that starts too deep leaves a crater. Tape on a plain twist bit is the fallback DIY Doctor describes when you have no collar.
Why does the small drill slip out?
The grub screw is loose, stripped, or bearing on a flat that is too small. EZARC and DECKRKAT reviews describe that failure, including a bit driven into plywood after the screw let go. Tighten the supplied key before the first hole. If the thread is already round, the bit is finished. Do not keep drilling while the body spins on the pilot.
Can I use an impact driver?
These listings mostly name a drill, a driver or a hex shank, not a licence to hammer the bit. An impact driver's blows are a good way to snap a 2 mm pilot, which is already a common review complaint on an ordinary drill. Use a drill clutch at a low setting. ATOPLEE's listing goes further and says hand drills are not allowed at all.
When do I stop and call someone?
Stop for structural screws, fire doors, calculated joints, and any countersunk fastener that is carrying load rather than holding a hinge. Stop for tile, concrete and masonry, and for mild steel if the bit only burnishes the edge. A joiner or a metalworker with the right cutter should take those holes. Swapping to another HSS set from this comparison does not make them DIY.

Related pages

Countersink drill bit buying guide

Countersink drill bit

82 or 90 degree countersink: match the screw in your hand

Best countersink drill bits for the screw in your hand

Countersink drill bit for wood: size the pilot first

Sources

Public UK sources from the research digest, last checked on 19 October 2026. Shelf prices and star lines are the amazon.co.uk figures in the display file.

  1. HSE: PUWER overview (retrieved 19 October 2026)
  2. HSE WIS23: wood dust (retrieved 19 October 2026)
  3. HSE: cutting and sanding wood (retrieved 19 October 2026)
  4. HSE L25: eye protection (retrieved 19 October 2026)
  5. GOV.UK: General Product Safety Regulations 2005 (retrieved 19 October 2026)
  6. Consumer Rights Act 2015, section 20 (retrieved 19 October 2026)
  7. Screwfix: screws buying guide (retrieved 19 October 2026)
  8. BSI: BS EN ISO 10642:2019 (retrieved 19 October 2026)