Countersinks and their applications
A countersink or countersink cutter is used to chamfer a drill hole or to make a countersink. When countersinking, the screw or bolt sits deeper in the material so it does not protrude above the surface of the material.
Before countersinks can be used, a hole must be drilled or cut. The countersink itself cannot be used for drilling holes in the material.
Countersinks are therefore used for:
- Chamfering a hole to countersink a screw head into the material
- Applying a chamfer to a hole before threading
- Deburring a sharp edge of a hole
When to use which countersink?
Which type of countersink to use depends on the application such as a locating edge for a dowel pin, countersinking rivets or pop rivets in the aircraft industry, countersinking all kinds of screw threads, etc. There is a suitable countersink for any of these and other quests.
Two steps to select the correct countersink
Take these two steps to find the correct countersink or countersink cutter:
- Determine the number of degrees to be countersunk using the countersink - 90° is the most commonly used countersink, but versions with a top angle of 62°, 80°, 120°, and other top angles are available, too.
- Choose a countersink with a slanted hole, 1 cutting edge or 3 cutting edges - countersinks with a slanted hole are very suitable for use in wood, hard plastics and aluminium. Countersinks with 1 cutting edge are suitable for deburring and light countersinking and can be used on light metal and plastics. Countersinks with 3 cutting edges are universal in use, self-centring and have low vibration in the variable tooth pitch version.
Benefits of variable tooth pitch countersinks
The most commonly used countersinks also come with variable tooth pitch or spacing.
These 3-cutter countersinks for universal use have three main benefits:
Productivity - Variable pitch countersinks are 30% faster than standard countersinks.
Ergonomics - Countersinks with variable tooth pitch require less effort when used manually and are therefore ergonomic to use.
Sustainability - Due to reduced vibration and pressure exertion, variable pitch countersinks stay sharp on the cutting edges for a long time and therefore last longer than standard countersinks.
Countersinking using other tools
Sometimes, it is more appropriate to choose other tools instead of a countersink or countersink cutter.
A step drill provides drilling and countersinking in one operation.
A counterbore is used for countersinking hexagonal screws, cylinder screws and for stud pre-drilling.
A multi-diameter step drill centres, drills, deburrs and countersinks in a single operation. Ideal for machining in sheet metal and thin plate material.