7 mm Drill Interface
D175.070R is the exact right-hand D175 configuration for a 7 mm metric drill, using an 18 mm shell diameter.


Right-hand carbide-tipped shell countersink for use with compatible Royce Ayr D100–D155 metric drills. The verified D175.070R configuration uses a 7 mm drill interface, 18 mm shell diameter, two cutting edges, and set-screw attachment for producing a 90-degree screw-head countersink.
Carbide-tipped two-edge shell countersink designed to mount directly onto the twist of a compatible metric drill. The shell forms a 90-degree screw-head countersink while the installed drill performs the pilot-hole operation.
Specified for use with Royce Ayr D100–D155 metric drills. D175.070R is the right-hand 7 mm version with an 18 mm shell diameter and set-screw retention.
The Royce Ayr D175.070R is a carbide-tipped shell countersink engineered for use with compatible D100–D155 metric drills. The exact current configuration is a 7 mm drill interface, 18 mm shell diameter, two cutting edges, and right-hand rotation.
The shell fastens onto the twist of the drill with a set screw, allowing the drill and countersink to operate as a combined setup. Royce Ayr specifies the D175 series for producing a 90-degree screw-head countersink in CNC drilling and cabinet-component production.
Because the countersink mounts directly to the drill, correct drill compatibility and concentric installation are critical. Verify the 7 mm drill size, right-hand rotation, set-screw engagement, shell clearance, runout, spindle condition, drilling depth, feed rate, RPM, extraction, and workpiece support before production.
Technical Specifications
D175.070R is the exact right-hand D175 configuration for a 7 mm metric drill, using an 18 mm shell diameter.
Two carbide-tipped cutting edges provide the verified Z2 geometry for the shell countersink while preserving the D175 compact mounting concept.
The shell fastens directly onto the twist of a compatible D100–D155 drill with a set screw to create a combined pilot-drill and 90-degree countersink setup.
Confirm that the selected Royce Ayr D100–D155 drill provides the exact 7 mm interface required by D175.070R and that the machine setup requires right-hand rotation. Seat the shell concentrically on the drill twist, tighten the set screw securely, and verify drill condition, shell clearance, runout, countersink depth, RPM, feed rate, extraction, and workpiece support before production.
Royce Ayr D175.070R combines a 7 mm drill interface, 18 mm shell diameter, two carbide-tipped cutting edges, right-hand rotation, and set-screw mounting in the D175 shell-countersink format.
It is designed to pair with compatible D100–D155 metric drills so the pilot hole and 90-degree screw-head countersink can be produced in a coordinated CNC drilling setup.