Metric A2 Stainless Steel Cone Point Set Screws
Metric Cone Point Set Screws in A2 (18-8) Stainless Steel—also called pointed set screws, cone point grub screws, piercing point set screws, or sharp point set screws—feature a hardened conical tip that delivers the maximum holding power of any set screw point style. The sharp cone point is designed to seat into a pre-drilled indentation (detent) in the shaft or pierce directly into softer materials, creating a permanent mechanical interlock that provides exceptional resistance to rotation and axial movement. Combined with A2 stainless steel corrosion resistance, these set screws are ideal for permanent or semi-permanent installations in harsh, wet, or corrosive environments.
How Cone Point Set Screws Work
Cone point set screws function through aggressive mechanical engagement with the mating surface. When tightened, the sharp conical tip either seats into a matching conical indentation machined into the shaft (providing precise centering and maximum contact area) or pierces directly into the workpiece material (creating its own locking detent). In both cases, the cone point creates a physical interlock that goes beyond friction-based holding—the shaft cannot rotate or slide without shearing through the embedded point or deforming the mating indentation. This makes cone point set screws virtually immune to loosening from vibration, shock, thermal cycling, and dynamic loads when properly installed.
Maximum Holding Power—With Trade-Offs
Cone point set screws offer the highest holding power of any point style, but this performance comes with important considerations. The sharp point creates permanent damage to the shaft surface, leaving a deep indentation or hole that cannot be easily repaired. This makes cone point set screws unsuitable for applications requiring frequent adjustment, repositioning, or component reuse. Additionally, once removed, a cone point set screw may not hold as securely if reinstalled in the same location—the previously created indentation may not align perfectly with the point, reducing contact and grip. For these reasons, cone point set screws are best reserved for permanent installations where maximum holding power is the primary requirement.
When to Use Cone Point vs. Other Point Styles
Selecting the correct set screw point style depends on balancing holding power, surface damage, and adjustability:
- Cone Point: Maximum holding power with permanent shaft damage—best for permanent installations, high-torque applications, and assemblies where loosening is unacceptable
- Cup Point: Excellent holding power with significant shaft marking—best for semi-permanent installations; the most common general-purpose choice
- Knurled Point: Good holding power with moderate shaft marking—best for applications requiring occasional repositioning while maintaining secure grip
- Flat Point: Minimal holding power with no shaft damage—best for frequent adjustment against hardened surfaces or when shaft protection is critical
- Oval Point: Low holding power with minimal shaft damage—best for frequent adjustment, often used with a shaft groove
- Dog Point: Positive mechanical engagement into a mating hole—best for precise alignment and anti-rotation when a keyway or hole is present
Choose cone point when the installation is permanent, when maximum resistance to rotation and loosening is required, and when shaft damage is acceptable.
Using Cone Points with Mating Indentations
For optimal performance, cone point set screws should be used with a pre-drilled conical indentation (detent) in the shaft at the desired locking position. This indentation is typically created using a center drill or countersink that matches the cone angle of the set screw point (usually 90° or 120°). The mating detent provides several advantages: it precisely locates the component on the shaft, maximizes the contact area between the cone point and shaft material, distributes stress more evenly, and allows the set screw to be removed and reinstalled in the exact same position with full holding power. When a mating indentation is not feasible, cone point set screws can still pierce into softer shaft materials—but a matching detent is strongly recommended for critical applications.
Why Choose A2 (18-8) Stainless Steel?
A2 stainless steel—also known as 18-8 or 304 stainless, is the most widely used stainless steel grade for fasteners worldwide. The designation "18-8" refers to the approximate composition: 18% chromium and 8% nickel. This combination creates a passive oxide layer on the surface that provides excellent resistance to corrosion, rust, and staining in most atmospheric conditions and many chemical environments. A2 stainless steel is non-magnetic in the annealed condition and offers good strength for general-purpose fastening applications. For cone point set screws, A2 stainless provides reliable permanent holding in environments where carbon steel or alloy steel would corrode over time.
Material Properties & Specifications
Our metric A2 stainless steel cone point set screws are manufactured to metric sizing standards with internal hex (Allen) socket drive for flush installation. A2 stainless steel provides a minimum tensile strength of approximately 500-700 MPa (70,000-100,000 PSI) depending on size—suitable for most general-purpose applications. The cone point is precision-machined to create a consistent angle that provides reliable centering and maximum engagement with mating indentations. A2 stainless performs well in temperatures ranging from cryogenic up to approximately 800°F (425°C) for intermittent exposure.
A2 vs. A4 Stainless Steel
Both A2 and A4 are austenitic stainless steels offering excellent corrosion resistance, but they differ in specific capabilities. A2 (18-8 / 304) provides excellent corrosion resistance for most environments and is the standard choice for general-purpose stainless fasteners at economical pricing. A4 (316) contains added molybdenum, providing superior resistance to chlorides, salt water, and aggressive chemical environments—but at higher cost. Choose A2 for general corrosion resistance in most applications; choose A4 for marine, coastal, swimming pool, chemical processing, or high-chloride environments where maximum corrosion resistance is essential.
Important Considerations
Because cone point set screws create permanent shaft damage, they should be reserved for applications where repositioning is not anticipated. If the component may need adjustment during installation, consider using a cup point or knurled point set screw during setup, then replacing it with a cone point for final permanent assembly. Always verify the correct position before fully tightening a cone point set screw, as removal and reinstallation in a new location will leave the original indentation in the shaft. For shafts that must remain unmarked or reusable, consider flat point, oval point, or brass-tipped set screws instead.
Common Applications
Metric A2 stainless steel cone point set screws are specified across industries where permanent holding power and corrosion resistance are both required:
- Food & Beverage Processing: Permanent shaft collars, fixed sprockets, conveyor drive components in washdown environments
- Marine & Coastal: Deck hardware, permanent pulley installations, equipment exposed to salt air and moisture
- Medical & Laboratory: Permanent assemblies in sterilizable or autoclave-compatible equipment
- Pumps & Motors: Impeller locking, coupling assemblies, permanent rotor positioning
- Industrial Machinery: Gear and sprocket mounting, high-torque shaft assemblies, critical drive components
- Outdoor & Architectural: Permanent fixtures, signage hardware, equipment exposed to weather
Installation Tips
For maximum holding power, use a mating conical indentation drilled at the correct location on the shaft. Ensure the shaft surface is clean and free of oil, grease, or debris. Use the correct size hex key (Allen wrench) and tighten to manufacturer-recommended torque specifications—the cone point should seat firmly into the indentation or penetrate the shaft material. Over-tightening can strip threads or crack brittle shaft materials. Stainless steel can gall when threaded against other stainless components—consider using anti-seize compound on threads when installing into stainless tapped holes to facilitate future removal if needed.
Available Sizes
We stock metric A2 stainless steel cone point set screws in a range of popular thread sizes and lengths to cover most permanent positioning applications. Albany County Fasteners offers competitive bulk pricing and same-day shipping on in-stock items.
Need alloy steel, a different point style, or a specific size? Contact our team—with over 18 million fasteners in stock, we can help you source the right set screw for your application.