Illustrated explanation
2Spot-faceRecess shapes provide different seating and clearance
- Counterbore / countersink
The two recess profiles are different. Specify the exact form and depth required for the mounting component.
- Spot-faceThis term
The local machined land provides a defined seating face. Check its size, flatness and finish for the actual gasket or washer.
- Undercut
The recess provides clearance near a transition or shoulder. Keep it separate from usable full-form thread engagement.
A counterbore has a cylindrical recess, a countersink has a conical form, a spot-face creates a seating surface and an undercut provides local relief.
Conceptual machining sections without depths or angles. Confirm each feature from the actual enclosure and accessory drawings.