4-40 x 5/8 Flat Point Alloy Steel Socket Set Screw with Nylon Insert identifies the exact thread and length for an alloy steel flat point set screw with a nylon insert. The flat point clamps by friction, so it is commonly chosen for shafts that should not be intentionally marked by a biting point. Use the heat-treated alloy steel body with the nylon locking pellet where the application calls for mechanical fastening rather than stainless material.
Handle and control retention often benefits from a headless screw that can be serviced from the socket end. Because the insert is polymer, review heat exposure when the application would otherwise use an all-metal screw.
The nylon pellet is added to create thread drag while leaving the flat bearing face responsible for shaft contact. For replacement work, Cold Headers helps keep thread, length, material story, point style, and insert function aligned. Check thread size, length, socket size, pellet dimensions, shaft-flat condition, and surface-marking tolerance before substitution.
Technical Highlights
- Point: Flat (full bearing face)
- Material: Alloy Steel
- Thread Size: 4-40
- Length: 5/8 in.
- Drive: Internal Hex
- Hex Key Size: 0.050 in.
- Locking Feature: Nylon insert providing prevailing torque
- Nylon Insert Diameter (P): 1/16 in.
- Nylon Insert Location (N): 3/32 in., +/-1/2 pitch
- Dimensional Standard: ASME B18.3
Call 773-775-7900 or email Sales@coldheaders.com for pricing, availability, or a quote.
