4-40 x 7/16 Flat Point Alloy Steel Socket Set Screw with Nylon Insert is specified when friction clamping and thread-level locking are both required in a headless fastener. Flat point geometry favors surface protection and repeatable adjustment rather than maximum bite into the mating part. Use the heat-treated alloy steel body with the nylon locking pellet where the application calls for mechanical fastening rather than stainless material.
Large 5/8 flat point nylon-insert sizes support heavier collars and hubs where the print still calls for shaft-friendly contact. ASME B18.3 places flat point diameter in a qualitative band of about 0.55-0.62 times nominal screw diameter, so confirm the mating seat rather than substituting a sharp point. Do not treat plain alloy steel as corrosion resistant; protect or oil the part when the environment demands it.
Cold Headers has supplied specialty socket fasteners since 1962 and keeps point style, insert type, and size language clear. Check size, socket, pellet dimensions, and surface-marking tolerance before substitution.
Technical Highlights
- Point: Flat (full bearing face)
- Material: Alloy Steel
- Thread Size: 4-40
- Length: 7/16 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.
