5/8″ UNC Grade 5 Zinc Hex Set Screws

Product Description

5/8″-11 UNC Grade 5 Zinc-Plated Hexagon Set Screws

Fully threaded 5/8″ UNC hexagon-head set screws manufactured from high-tensile steel with a zinc-plated finish. The 5/8″-11 Unified National Coarse thread has 11 threads per inch and is suitable for automotive, engineering, machinery, fabrication and general maintenance applications.

These fasteners have a standard 15/16″ hexagon head for installation using a suitable spanner or socket. The zinc-plated finish provides additional corrosion protection compared with untreated steel in normal indoor and sheltered environments.

Product Details

• Nominal thread size: 5/8″ UNC
• Thread designation: 5/8″-11 UNC
• Threads per inch: 11 TPI
• Thread form: Unified National Coarse
• Material: High-tensile carbon steel
• Mechanical grade: SAE Grade 5 – subject to supplier certification
• Finish: Zinc plated
• Head style: External hexagon head
• Spanner or socket size: 15/16″ AF
• Nominal head height: 3/8″
• Thread coverage: Fully threaded – verify against stock
• Available lengths: 1″, 1 1/4″, 1 1/2″ and 2″

Length measurement: Hexagon-head screw length is measured from beneath the head to the end of the fastener.

Standards Information

SAE J429 is the relevant mechanical and material specification commonly used for inch-series Grade 5 steel fasteners. ASME B18.2.1 is the applicable dimensional reference for inch-series square and hexagon bolts and screws.

Compliance with either standard should only be claimed when supported by the supplier's dimensional information, grade markings and material certification. Metric property class 8.8 is not the formal grade designation for a UNC fastener.

Typical Applications

• Automotive and commercial-vehicle assemblies
• Machinery and industrial equipment
• Engineering and steel fabrication
• Brackets, guards and equipment housings
• Agricultural machinery
• General imperial-threaded repairs

Installation Guidance

• Use a correctly fitting 15/16″ AF spanner or socket.
• Use only with compatible 5/8″-11 UNC nuts or tapped components.
• Do not interchange UNC and 5/8″-18 UNF threads.
• Select a tightening torque appropriate for the joint and confirmed grade.
• Replace fasteners showing damaged threads, corrosion or rounded heads.

Zinc plating provides limited corrosion protection but is not intended for prolonged marine exposure or highly corrosive environments. A suitable stainless-steel or specialist coated fastener may be preferable for those conditions.

Specifications are provided as a guide. Where dimensions, grade or mechanical performance are critical, please contact us before ordering.

Please Note: Specifications given are intended as a guide only. If critical to your project please check with us first.