MS90727 Grade 8 fine-thread hex cap screws.

// REFERENCE SIZES

MS90727 part-number and dimension table

Reference sizes for identification and quotation. Webson confirms availability by inquiry; these rows do not indicate stocked inventory.

Head across-flats width and axial head height are minimum–maximum drawing limits in inches. Length values preserve the reviewed table’s decimal references, including 0.438 and 0.562; they do not add acceptance tolerances. Across-flats limits describe the screw head, not the tolerance of a wrench or socket.

// MEASUREMENT GUIDE

Measure under-head length and head dimensions

Length L runs from the bearing surface beneath the head to the tip. H is the axial head height; F is the width between opposite hex faces. The head is outside the under-head length measurement.

Thread length is a separate requirement. The reviewed issue uses a minimum rule of twice the nominal diameter plus 1/4 inch, with a positive allowance and separate provisions for screws too short to provide that thread length. Use the full governing issue for those limits. A listed screw length is not a fixed grip length or a claim that the screw is fully threaded.

// ORDERING EXAMPLES

Read the complete part number

MS90727-3 is a 1/4-28 reference with a 0.500-inch under-head length. MS90727-109 is a 1/2-20 reference with a 1.000-inch under-head length. Use the full series and dash number when ordering.

// MATERIAL AND CONFIGURATION

Preserve the finish and locking requirement

The reviewed MS90727F reference specifies alloy steel, Grade 8, with zinc coating. Earlier issues used cadmium plating; retain the coating and specification issue called out by your drawing.

The table lists plain screws. The reviewed part-number requirements use an L after the dash number for a self-locking element. Preserve that suffix and the locking requirement when applicable; a plain screw and a locking configuration are separate selections.

// FAMILY COMPARISON

Compare the four hex cap screw families

Compare grade, thread, finish and governing issue together. A similar head size does not establish an approved substitution. Select mating nuts and washers to the application’s strength, finish and dimensional requirements.

// DRAWING REQUIREMENTS

Match the governing drawing issue

Dimensions summarize MS90727F, sheets 1–3, 4 November 1988. These are selected historical references for purchasing identification. The issue required by your drawing controls full dimensions, thread length, material, coating, locking and inspection requirements.