Definition of countersink in English:



[with object]
  • 1Enlarge and bevel the rim of (a drilled hole) so that a screw, nail, or bolt can be inserted flush with the surface.

    ‘drill and countersink the hole for mounting the ladder to the wall’
    • ‘All the clamp holes of the panels were countersunk with this bit so that the screw heads are flush.’
    • ‘Drill four 3/16-inch clearance holes in each rib before countersinking the top surface to bring the screw head flush.’
    • ‘Construction began by countersinking the holes for the bolster rivets slightly.’
    • ‘Drill and countersink screw holes for mounting screws.’
    • ‘I've also countersunk the holes so no screwheads stick up later on.’
    1. 1.1 Drive (a screw, nail, or bolt) into a countersunk hole.
      ‘countersunk screw heads’
      • ‘It's helpful to first pre-drill a small hole in the wood where you want to countersink the brass screws.’
      • ‘Depending on how far the bolts stick out beyond the boards, we either countersink the nuts or wrap two layers of duct tape over the ends of the bolts to prevent damage to the greenhouse film.’
      • ‘Fasten the bottom of each brace with a 6-inch machine bolt and countersink the washer and nut.’
      • ‘To help prevent recurrence, countersink the nails and swab the holes with a water repellent.’
      • ‘A thin layer of thinset adhesive is applied to the top of the plywood using a notched trowel, then the cement board is put in place and secured with flathead screws that are countersunk into the surface.’
      • ‘When applying directly over an old floor, countersink any protruding nails and sand off any paint, wax, or varnish that might affect the adhering ability of the adhesive.’
      • ‘You can even countersink and cover the screws with a dab of caulk.’
      • ‘Flat heads are always countersunk or rest flush with the surface.’
      • ‘Use 12 or 16 HDG finishing nails and countersink them with a nail set.’
      • ‘Nail heads should be flush with the surface, but not countersunk as it can cause the backer board to crack or break.’
      • ‘Imagine driving a two-inch finish nail into solid oak with no predrilling and having it perfectly countersunk, all in less time than it takes to pick up a hammer.’
      • ‘Use a nail punch to countersink all nail heads approximately 1/8 ‘below the wood surface.’’
      • ‘Just get plenty of screws in and make sure that they are countersunk and that they hit the studs.’
      • ‘There is a second layer of plexi to attach to this, so I countersunk the screwheads so they were flush’
      • ‘I used regular wood screws and countersunk them in the PVC to allow a flush surface.’
      • ‘After the first sanding, check to see if any nails are now protruding, and, if so, countersink them.’
      • ‘Search out any protruding nail heads and countersink them with a nailset.’
      • ‘Then secure with 1-inch drywall screws, making sure they are countersunk.’
      • ‘First, countersink the nails and swab the holes with a water repellent.’
      • ‘Keep in mind, if you are using spring metal, that the nail heads should be slightly countersunk so that they do not catch on the opposite rail when the window is opened.’