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Structural bolts are critical components in any construction or heavy-duty assembly project, ensuring the integrity and safety of the final structure. Selecting the right type, size, and material for your needs is paramount to prevent premature failure and ensure long-term stability. This guide will help you navigate the options and make an informed decision for your next project.
Quantity & Size: You will get 1lb box (approx. 20pcs screws) #14 x 6" long lag screws concstruction wood screws, black, a T30 star bit
Rust Resistant: Our heavy duty lag screws are made from carbon steel and epoxy exterior black coating, with high hardness and great corrosion resistance, passed 2000h salt spray test, withstand the weather for outdoor use
Torx Drive: Torx drive lag screw bolt uses T30 star bit, taking high pressure torque without stripping. Large wide truss head or washer head won't over countersink into the material
Knurled Shank: The long wood screws feature knurled shank that expands the screw hole, facilitating easy settling, self-tapping cut for easy drilling, prevent wood cracking
【PRODUCT NAME】 20 sets lag bolts for wood, with 1/4 bolt and 1/4 stainless washer stainless steel bolts, various sizes and precise threads for different usage. Stainless steel hex head screws. Package includes: 20 pcs 1/4"x2" bolts + 20 pcs flat...
【MATERIAL】 High quality 304 stainless steel screws and bolts. Mywish lag screws have been rigorously tested, higher heat resistance, corrosion resistance and anti-rust effect in different extreme environment. Strong solid structure and longer...
【WIDE RANGE OF APPLICATIONS】 40 pieces cost effective bolt kit. Stainless hexagonal head screw are suitable for furniture assembly (beds, tables, cabinets, chairs, etc.), woodworking projects (joining wood, boards, workbench, kitchen worktops). Lag...
【PACKAGING】 40 Pieces 1/4 stainless steel bolts kit, comes with sturdy and reusable transparent storage container. Label with the size and quantity of hex bolts. Easy to distinguish the size of 1/4 bolt. Provide variable solutions to meet diverse...
Time-Saving and Effortless: These heavy-duty structural wood screws can secure landscape walls, decks, and post & beam construction without pre-drilling, saving you time and effort.
Anti-Corrosion Coating: Our black timber screws passed the 1000 Hour Salt Spray Test and remain fully functional even after prolonged exposure to the elements, resisting rust from sun and rain.
Professional Design: Our Heavy-Duty wood screws with serrated thread design provide stable connectivity, while the knurled shank reduces required drilling torque and prevents wood from cracking. With a notched tip, screwing is easier, saving you time and...
Versatile Applications: Ideal for various outdoor, home, and industrial projects, including deck building, log construction, and timber framing, these screws are compatible with ACQ lumber and multiple materials.
DURABLE CONSTRUCTION: Crafted from premium carbon steel, our wood screws are built to last and are compatible with ACQ-treated wood for long-lasting performance.
RUST-RESISTANT COATING: With a 4-layers coating that has passed a rigorous 1500 Hour Salt Spray Test, our lag screws provide superior protection against corrosion and rust, ensuring durability in even the harshest conditions.
EASY INSTALLATION: The knurled shank reduces the torque required for drilling, while the sharp threads and type 17 notched extra sharp point allow for effortless drilling without damaging the wood, saving you time and effort.
SLEEK DESIGN: The modified truss washer head design guarantees a sleek finish, elevating the appearance of your woodworking projects. The T30 star drive style ensures secure and efficient fastening without slippage.
DIMENSIONS & SUPERIOR STRENGTH: Thread Diameter 0.25" - Head Diameter 0.55" - Length 3" - Use with T30 Star Bit. Crafted from heat treated steel, LIONMAX heavy duty lag screws offer unmatched strength and reliability for long-lasting woodworking projects
ANTI-CORROSION COATINGS: The lag screws passed the 1000 Hour Salt Spray Test without coating failures. They come with double coatings that feature excellent protection against corrosion and rust, making them long-lasting even in harsh conditions
KNURL THREAD & SELF-TAPPING: The knurled shank significantly reduce drill torque requirements, and the deep, sharp threads allow easy drilling into the wood without damage. The type 17 notched extra sharp point makes screwing a breeze, reducing the need...
MODIFIED TRUSS WASHER HEAD & STAR DRIVE: The modified truss washer head design of structural lag screw provides a flush and neat finish, enhancing the overall appearance of your woodworking creations. Featuring a T30 star drive style, these wood screws...
HIGH-STRENGTH GRADE 8 STEEL Manufactured from Grade 8 steel for high tensile strength and load capacity. Designed to handle demanding fastening tasks that require durability, torque resistance, and dependable performance in heavy-duty applications.
HEX FLANGE DESIGN FOR SECURE HOLD: An integrated hex flange distributes clamping force evenly, reducing the need for separate washers and helping maintain a tight, stable connection. Ideal for frame, structural, and mechanical fastening needs.
BLACK PHOSPHATE & OIL FINISH: Features a black phosphate and oil coating that helps resist corrosion and wear. Suitable for use in automotive, machinery, agricultural, and workshop environments exposed to moisture or friction.
VERSATILE INDUSTRIAL APPLICATIONS: Well-suited for automotive frames, machinery assemblies, construction projects, agricultural equipment, and general industrial use. A dependable option for both professional mechanics and DIY builders.
INDUSTRIAL-GRADE DURABILITY: Crafted from carbon steel, LIONMAX wood screws withstand heavy loads and resist bending or shearing, providing rock-solid stability in wood structures like decks, sheds, or outdoor furniture
ANTI-CORROSION COATINGS: Construction lag wood screws passed the 1000 Hour Salt Spray Test. The black coating offers excellent protection against corrosion and rust, allowing them to be used even in humid climates, rainy environments, or salt-air coastal...
STAR DRIVE FLAT HEAD DESIGN: The T30 star drive design provides a secure grip, preventing unwanted slippage and stripping. Flat Countersunk Head sits flush with surfaces for safety and aesthetics, ideal for applications like flooring and trim work
EASY TO INSTALL: The knurled shank and sharp threads of the structural screws greatly reduce drill torque requirements, allowing for easy drilling into wood without causing any damage. The type 17 notched extra sharp point makes pre-drilling unnecessary
PROFESSIONAL FASTENING PERFORMANCE: Delivers strong, secure through-bolt connections while maintaining a clean, finished appearance. These timber bolts eliminate exposed bolt ends, improve safety, and ensure reliable fastening performance.
PRECISION-ENGINEERED FASTENING DESIGN: Features tightening sleeve technology that secures firmly in place while adjusting to varying material thickness, simplifying installation and eliminating the need to trim excess bolt ends.
POWDER-COATED STEEL CONSTRUCTION: Made from heavy-duty steel with a durable powder coating designed to resist corrosion, moisture exposure, and environmental wear for long-term indoor and outdoor performance.
VERSATILE BUILDING APPLICATIONS: Designed for pergolas, decks, beams, posts, pavilions, and structural wood installations using OZCO or compatible systems, supporting secure wood-to-wood connections with a clean finish.
Last update on 2026-10-14 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Structural Bolts
Understanding Structural Bolt Types
Structural bolts are designed to withstand significant loads and stresses. The most common types include:
Hex Bolts: These are versatile and widely used for general construction and machinery applications. They feature a hexagonal head for easy tightening with a wrench.
Carriage Bolts: Characterized by a smooth, domed head and a square neck, carriage bolts are ideal for wood construction as the square neck prevents rotation when the nut is tightened.
Anchor Bolts: Used to connect structures to concrete foundations, anchor bolts come in various shapes like J-bolts and L-bolts, embedding into the concrete to provide a strong anchor point.
Key Material Considerations
The material of a structural bolt significantly impacts its strength, corrosion resistance, and suitability for different environments.
Steel: The most common material, offering excellent strength. Steel bolts are often coated (e.g., galvanized) to resist rust. High-strength steel alloys are used for demanding applications.
Stainless Steel: Offers superior corrosion resistance, making it ideal for outdoor or marine environments where exposure to moisture and salt is a concern.
Alloy Steel: Used for bolts requiring exceptional strength and durability, often in high-stress industrial applications.
Determining the Right Size and Strength
Bolt size is determined by its diameter, length, and thread pitch. Strength is typically indicated by a grade system (e.g., Grade 2, 5, 8 for standard steel bolts, or specific ASTM/SAE grades for structural applications).
Diameter: Choose a diameter that can handle the anticipated shear and tensile loads.
Length: The bolt should be long enough to pass through all connected materials with at least two full threads protruding beyond the nut.
Strength Grade: Match the bolt's strength grade to the load requirements of your project. Consult engineering specifications or load charts if unsure.
Essential Accessories: Washers and Nuts
Properly selected washers and nuts are crucial for secure and effective bolt installation.
Washers: Distribute the load evenly, prevent damage to the material surface, and can help maintain tension. Flat washers are common, while lock washers prevent loosening due to vibration.
Nuts: Must match the bolt's thread size and material grade. Hex nuts are standard, but locking nuts provide extra security in vibration-prone environments.
Comparison Tips for Selection
When comparing options, consider the following:
Application Environment: Will the bolt be exposed to moisture, chemicals, or extreme temperatures?
Load Requirements: What are the expected tensile and shear forces the connection will endure?
Material Compatibility: Ensure the bolt, nut, and washer materials are compatible to avoid galvanic corrosion.
Compliance Standards: For structural applications, ensure bolts meet relevant industry standards (e.g., ASTM, ASME).
Frequently Asked Questions
What is the difference between a regular bolt and a structural bolt?
Structural bolts are specifically engineered and manufactured to meet stringent standards for load-bearing applications in construction and heavy industry. They typically have higher tensile and shear strength ratings compared to standard bolts.
How do I determine the correct bolt grade for my project?
Bolt grade indicates its strength. For structural applications, consult engineering plans or load charts to determine the required strength grade that can safely support the intended load. Higher grades offer greater strength.
What does 'galvanized' mean for a bolt?
Galvanized bolts are coated with a layer of zinc to protect them from rust and corrosion. This coating makes them suitable for outdoor use or in environments where moisture is present.
Can I use stainless steel bolts outdoors?
Yes, stainless steel bolts are an excellent choice for outdoor applications due to their superior resistance to corrosion and rust. They maintain their integrity even when exposed to weather elements.
What is the purpose of a washer with a structural bolt?
Washers help distribute the clamping force over a larger surface area, preventing damage to the material being joined. They also ensure a more uniform tension and can prevent the bolt head or nut from digging into the surface.
How do I measure the length of a structural bolt?
For bolts with a hex or flat head, measure from the underside of the head to the bolt's tip. For bolts with a washer face under the head, measure from the top of the head to the tip. Ensure the length accounts for the thickness of materials and nut.
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