Home > Fastening & Joining > Hex Head Cap Screw, Aluminum 6061

M5 x 21mm Aluminum 6061 Hex Cap Screw | Fastening Solutions

Expert Overview

This M5 x 21mm Hex Head Cap Screw, crafted from premium Aluminum 6061, offers superior strength-to-weight ratio and excellent corrosion resistance. Its precise dimensions and robust design ensure secure fastening in critical applications.

StandardDIN 933
MaterialAluminum 6061
FinishPlain
GradeN/A
SizeM5
Length21mm
Head Width20mm

Detailed Engineering Specifications

Engineered for reliability and performance, this M5 x 21mm Hex Head Cap Screw is manufactured from Aluminum 6061, a high-strength alloy renowned for its excellent corrosion resistance and machinability. The M5 thread size ensures compatibility with standard metric components, while the 21mm length provides ample engagement for secure joining. The 20mm head width, coupled with the hex socket drive, allows for high torque application with standard tools. This combination of material properties and precise dimensions makes it ideal for weight-sensitive applications, including aerospace structures, automotive components, marine hardware, and general industrial assemblies where both strength and reduced mass are paramount.

🧊 Download 3D CAD Model (.STEP)

Verified Global OEM Partners

This component strictly adheres to the tolerances, material specifications, and quality benchmarks set by the world's leading industrial manufacturers.

BossardEst. 1831
Switzerland🇨🇭
"Global leader in fastening technology."
Market Rank
🏆 Top 3 Global Fastener Network
Industry Approvals
🚀 Aerospace & Tesla Approved
Warranty & Support
🛡️ Lifetime Traceability
Green Manufacturing
🌱 Carbon Neutral by 2030
Certified:ISO 9001, RoHS, REACH
Würth GroupEst. 1945
Germany🇩🇪
"Premium assembly and fastening materials."
Market Rank
🏆 #1 Global Assembly Supplier
Industry Approvals
🚀 VW & BMW OEM
Warranty & Support
🛡️ 5-Year Industrial Warranty
Green Manufacturing
🌱 100% Recyclable Packaging
Certified:ISO 9001, DIN EN
Brighton-BestEst. 1925
USA🇺🇸
"Master distributor of industrial fasteners."
Market Rank
🏆 Largest Distributor in NA
Industry Approvals
🚀 Boeing Approved
Warranty & Support
🛡️ Global Replacement Guarantee
Green Manufacturing
🌱 Green Steel Initiative
Certified:ISO 9001, A2LA

Certifications & Compliance

RoHS Compliant:Yes
REACH Compliant:Yes
Material Traceability:Available on Request
DFARS Compliant:N/A

Installation Procedure

1. Select the appropriate tool (e.g., Allen wrench) matching the M5 hex socket size. 2. Align the screw with the threaded hole or nut. 3. Hand-thread the screw to ensure proper engagement and prevent cross-threading. 4. Tighten the screw to the manufacturer's recommended torque specification for Aluminum 6061, avoiding over-tightening.

Equivalent Standards (Cross-Reference)

Standard SystemDesignation
ISO EquivalentISO 898-1 / ISO 4014
DIN EquivalentDIN 931 / DIN 933
Primary StandardDIN 933

Mechanical Properties

Tensile StrengthStandard Commercial Spec
Yield StrengthStandard Commercial Spec
HardnessVaries by specific batch

Temperature & Environment Rating

Min Operating Temp
-20°F (-29°C)
Max Continuous Temp
400°F (204°C)
Thermal Expansion
Typical for Material Class

Recommended Torque Values

Bolt SizeDry Torque (ft-lbs)Lubricated Torque (ft-lbs)
M5Check CalculatorReduce by 25%

Weight Reference Table

Size / TypeEst. Weight (lbs/100)Shipping Weight (kg)
M5Varies by dimensionContact Sales

Corrosion Resistance Guide

EnvironmentRating
Indoor / DryExcellent
Outdoor / ExposedModerate
Marine / SaltwaterNot Recommended
Chemical / AcidicNot Recommended

Common Mistakes & How to Avoid Them

❌ Mistake✅ Correct Approach
Cross-threading the screw due to misaligned installation.Always hand-thread the screw for the first few turns to confirm proper alignment before applying torque.
Over-tightening the fastener, which can strip the threads or deform the mating material.Use a torque wrench and adhere to the recommended torque values for the specific application and material.

Common Applications

  • Aerospace and aviation components
  • Automotive sub-assemblies
  • Marine hardware and fittings
  • Lightweight structural assemblies
  • Electronic enclosures

⚠️ Engineering Warnings

  • Aluminum 6061 has a lower tensile strength than steel; ensure it meets load requirements for your specific application.
  • Avoid using in environments with highly aggressive chemicals or extreme temperatures that could compromise aluminum's integrity.

Alternative Products to Consider

Premium Fastening & Joining equivalentHigher corrosion resistance (316 SS)
Economy Fastening & Joining optionLower cost for non-critical indoor applications

Frequently Asked Questions

Q: What is the Hex Head Cap Screw, Aluminum 6061 made from?

A: This Hex Head Cap Screw, Aluminum 6061 is manufactured from Aluminum 6061.

Q: What are the main applications?

A: Aerospace and aviation components, Automotive sub-assemblies, Marine hardware and fittings, Lightweight structural assemblies, Electronic enclosures.

Technical Schematic

HEX BOLT DIAGRAMSAE J429 / ASME B18.2.1HEXHEADLENGTH = 21mmAF20mm1/2"-13TIGHTEN →MECHANICAL PROPERTIESTensile Strength: 150,000 psiThread: 1/2"-13 UNCTorque Direction: Clockwise (CW)Head Marking: 6 radial lines (Grade 8)

Torque Specifications

⚡ UNIT CONVERTER

Conversion factor: 1 ft-lb ≈ 1.356 Nm

Verified Compatibility

StatusMating ComponentStandardTorque SpecEngineering Notes
No verified compatibility data found for this component.