Buy Bolts Online in Australia
Bolt Selection — Quick Reference
Bolt selection turns on thread standard (metric/UNC/BSW), grade (load capability), material (steel/stainless), head type (hex/flange/cup head), and size. Wrong choice = strip + fail + costly rework. AIMS stocks 1,000+ bolt SKUs covering trade + maintenance use.
| Bolt Type | Common Use | Available Grades |
|---|---|---|
| Hex Bolt (Standard Setscrew Head) | General fastening — workshop default | Metric: 4.6 / 8.8 / 10.9 / 12.9 + 304/316 SS + Bumax 88/109/125 |
| Flanged Bolt (Built-In Washer Flange) | Vibration-resistant + uneven surface fastening | Metric 8.8 / 10.9 typ |
| Cup Head / Carriage Bolt | Timber + sheet — square shank prevents rotation | Metric + UNC, mild steel + galv |
| Set Screw (Full Thread) | Threaded fastening to nut or tapped hole — no shoulder | Metric + UNC, all grades |
| Hex Head Cap Screw (Partial Thread) | Where unthreaded shank carries shear load | Metric 8.8 / 10.9 / 12.9 + SS |
| Eye Bolt (Lifting + Tie Down) | Lifting points — see eye bolts | Forged + drop-forged + WLL rated |
| U-Bolt | Pipe + tube mounting — see u-bolts | Galv + zinc + SS |
| Plough Bolt (Square Head) | Bucket teeth + tipper bodies + earthmoving | Grade 5 + grade 8 high-strength |
Grade visual reference: Metric grade is stamped on bolt head: 4.6 (mild) / 8.8 (medium-high tensile) / 10.9 / 12.9 (high tensile). Imperial: SAE 2 (3 radial lines) / SAE 5 (3 lines) / SAE 8 (6 lines). Higher grade = higher tensile strength but lower ductility. Thread standards: METRIC for AU/EU machinery, UNC/UNF for US-origin, BSW for vintage AU/UK. Brands: Bremick, Hobson, Inox World, Bumax. Companion: all fasteners, hex bolts & nuts, bolt grade chart, metric bolt torque chart.
Bolts
AIMS Industrial stocks bolts across metric, UNC and BSW thread forms — in zinc-plated high tensile, 304 stainless, 316 stainless and specialty grades including Bumax high-strength stainless. The range covers hex bolts, flanged bolts, cup head (carriage) bolts and set screws, plus assortment kits for trade and maintenance use.
Metric High Tensile Bolts
Grade 8.8 metric hex bolts are the standard structural fastener for mechanical assemblies in Australian industry. The Metric Hex Bolt Grade 8.8 High Tensile Zinc Finish covers the most common size range from M6 to M24. The Metric Hex Set Screw Grade 8.8 Zinc Finish is a fully threaded variant — preferred where full thread engagement is required through the joint. For flanged applications, the Hex Flanged Bolt Class 8.8 Zinc Yellow Passivate and Hex Flanged Serrated Bolt Class 8.8 Zinc Plated include an integral flange that distributes clamping load and eliminates the need for a separate washer.
Stainless Steel Bolts
Stainless fasteners are specified where corrosion resistance is a primary requirement — marine, food processing, chemical and outdoor structural applications. The Metric Hex Set Bolt Full Thread 304 Stainless Steel and Metric Cup Head Square Neck Bolt 316 Stainless Steel cover the most common stainless specifications. 316 stainless offers superior chloride and salt water resistance compared to 304 — preferred for coastal and marine environments.
UNC & BSW Imperial Bolts
Imperial bolts remain in service in older plant and equipment, mining machinery, and imported equipment that has not been re-fastened to metric. The UNC Hex Bolt Grade 5 High Tensile Zinc Finish covers standard UNC sizes. The BSW Hex Bolt & Nut Grade 2 Mild Steel Zinc Finish is a paired bolt-and-nut format for BSW thread applications in light structural and maintenance work.
Assortment Kits
Assortment kits reduce procurement effort and ensure a broad selection is on hand for maintenance and repair. The Champion CA365 UNF Set Screw, Bolt & Nut Assortment Kit — 365 pcs covers a wide range of UNF sizes and is well suited to workshop and service vehicle inventories.
Shop the full range of bolts above, or contact our team for expert advice on the right product for your application or reach out if you need a quote. Fast dispatch from our Australian warehouse.
Buy your bolt needs from AIMS today and also see our Hex Bolts, Nuts, Washers, Socket Head Cap Screws, Machine Screws and Fasteners ranges.
People Also Ask — Bolts (General)
Q: What's the difference between a bolt and a screw?
Traditionally: bolts are tightened with a nut (the threaded shaft passes through both components), screws are tightened by threading directly into the workpiece. In practice the terms overlap — many fasteners called 'bolts' (engineer bolts, machine bolts) actually thread into tapped holes without a nut. For purchasing and identification, the term is often interchangeable; the key spec is thread size, head style, length, and grade.
Q: What bolt grades does AIMS stock?
Carbon steel: Grade 4.6, 8.8 (workshop standard high-tensile), 10.9, 12.9 (highest tensile per ISO 898-1). Stainless steel: A2-70 (304 stainless), A4-70 (316 stainless) per ISO 3506. Specialty grades for specific applications. The grade is stamped on the head — 8.8 means 800 MPa tensile strength, 80% yield. Match the grade to the joint's load requirement; over-spec is fine, under-spec is unsafe.
Q: Metric or imperial — which do I need?
Modern Australian equipment, automotive, and construction is predominantly metric (M6, M8, M10 etc). Imperial (UNC, UNF, BSW) appears on US-origin equipment, older Australian heritage equipment, and some plumbing/specialty applications. For workshop kit, stock both — but most workshops use 80% metric, 20% imperial. Bolt is by far the most-stocked single fastener type.
Q: What head style should I use?
Hex head (common bolt head) is the workshop standard — wrench access from any direction. Socket head cap screw for tight spaces or counterbored applications. Button head for low-profile or aesthetic finish. Countersunk for flush mounting. Carriage bolt for wood with square shoulder lock. Match the head style to the assembly's tooling access and design requirements.
Q: How tight should I tighten a bolt?
Match torque to bolt grade, size, lubrication, and joint design. Published torque charts cross-reference these. For workshop guidance: M6 grade 8.8 = 9 Nm, M8 = 22 Nm, M10 = 45 Nm, M12 = 78 Nm in dry threads. Lubricated threads (anti-seize, oil) reduce target torque by 15-20% for the same clamp force. For critical bolting, always use a calibrated torque wrench rather than feel.