Unless otherwise specified, screws of longer nominal length have a minimum length of full form thread of 1.00 inch. Nominal lengths greater than 3 diameters, up to and including 1 1⁄8 inch, have full form threads extending to within two pitches (threads) of the bearing surface of the head, or closer, if practicable. 5 and smaller with nominal lengths equal to 3 diameters and shorter have full form threads extending to within 1 pitch (thread) of the bearing surface of the head, or closer, if practicable.

Threads for hexagon machine screw nuts may be either UNC or UNF, Class 2B, and for square machine screw nuts are UNC Class 2B. Thread dimensions for sizes 0000, 000, and 00 are given in Table 7 on page 1698. ThreadsĮxcept for sizes 0000, 000, and 00, machine screw threads may be either Unified Coarse (UNC) and Fine thread (UNF) Class 2A ( see American Standard for Unified Screw Threads starting on page 1865) or UNRC and UNRF Series, at option of manufacturer. Information on metric machine screws B18.6.7M is given beginning on page 1708. The Standard also covers flat trim head, oval trim head and drilled fillister head machine screws and gives cross recess dimensions and gaging dimensions for all types of machine screw heads.

Dimensions of various types of slotted machine screws, machine screw nuts, and header points are given in Tables 1 through 12. This Standard ANSI B18.6.3 covers both slotted and recessed head machine screws. American National Standard Machine Screws and Machine Screw Nuts Machine Screw, Head Type Fillister, 18-8 (304) Stainless Steel, Length 7/8 In., Drive Type Slotted, Finish Plain, Dia./Thread Size #6-32, Head Dia. They are installed into an existing or predrilled, pre-tapped hole and are fully threaded. Phillips Pan-Head Machine Screws (3-Pack) These machine screws are used with nuts or These machine screws are used with nuts or directly into a female threaded receptacle to fasten metal parts together. Machine Screw, Head Type Fillister, 18-8 (304) Stainless Steel, Length 1 In., Drive Type Slotted, Finish Plain, Dia./Thread Size #6-32, Head Dia.

6 32 machine screw slotted fillister