Our metric slotted set screws with flat point, manufactured to DIN 551 and ISO 4766, are headless grub screws driven by a flat blade screwdriver. The flat point bears against a shaft or a machined pad without biting into it, making these the standard choice for locating and clamping components that must be adjusted or removed without damage.

Slotted Set Screws with Flat Point in Metric Sizes

What Is a Slotted Flat Point Set Screw?

A slotted set screw with a flat point is a headless threaded fastener, driven by a screwdriver blade in a slot cut across one end, with a flat unhardened face at the opposite end. It is threaded fully along its length and sits inside a tapped hole, usually finishing flush with or below the surface. Its job is to clamp, locate, or adjust a component by pressing against a mating surface rather than by clamping two parts together as a bolt does.

The flat point is what distinguishes this screw from cup, cone, dog, and oval point variants. Because the flat face presses without penetrating, it protects the surface it bears on, which is essential when a collar, gear, or bearing must be repositioned along a shaft or removed for service. At Metric Specialties we stock these in steel and in A2 stainless, in the small diameters where slotted grub screws are most commonly specified.

Key Features and Benefits

• Non Marking Clamping: The flat face bears without digging in, protecting shafts and machined pads so parts can be adjusted or removed cleanly.
• Headless and Flush: The screw sits inside the tapped hole with nothing protruding, which suits rotating assemblies and tight clearances.
• Simple Slotted Drive: A common flat blade screwdriver drives it, requiring no hex key or specialist bit.
• Repeatable Adjustment: Ideal for setting and resetting position on a shaft, since the bearing surface is not damaged by successive tightening.
• Corrosion Options: Plain and plated steel for general work, plus A2 stainless for damp and exposed environments.

Materials and Finishes

• Steel Class 14H: The standard hardened grade for general machine building and drive components.
• A2 Stainless Steel: Corrosion resistant for outdoor, marine, food, and hygienic assemblies.
• Black Oxide and Zinc Plated: Alternative finishes for appearance and light corrosion protection indoors.

Standards Compliance

• DIN 551 and ISO 4766 cover slotted set screws with a flat point.
• ISO 898-5 defines the mechanical property classes for set screws, including Class 14H.
• ISO 4753 defines the point geometry that distinguishes flat, cup, cone, dog, and oval variants.

Common Applications and Industries

Slotted flat point set screws are used across power transmission, instrumentation, light machinery, model engineering, and electrical assembly. The classic application is holding a collar, pulley, gear, sprocket, or hub in position on a shaft, where the flat point presses on the shaft or on a machined flat and holds the component against rotation and axial movement.

They also serve as adjustable stops, hard limits, and levelling elements in jigs, fixtures, and light frames, where the screw sets a precise position and is then locked. Because the flat point leaves the mating surface unmarked, they are specified wherever the component must come off again for service, calibration, or repositioning, and they are widely used in instruments, small motors, and control hardware where the assembly is compact and the drive torque is modest.

How to Choose the Right Set Screw

Start with the point style, because it decides how the screw holds. Choose a flat point when the bearing surface must be protected and the part will be repositioned or removed, and choose a cup or cone point instead when you want the screw to bite in for maximum grip on a permanent setting. Then set the diameter from the size of the tapped hole in the hub or collar, and check the length so the screw sits below the surface with enough thread engaged behind it.

Match the material to the environment, taking hardened steel for general drive work and A2 stainless where moisture or hygiene is a factor, noting that stainless has lower hardness and a correspondingly lower holding torque. Consider the drive as well, since the slot suits modest torque and hand tools. Where higher tightening torque or powered assembly is needed, a hex socket set screw is the better fit. Finally, a machined flat on the shaft greatly improves the holding power of a flat point.

Size Range and Availability

Available in M1.6 through M12 in metric coarse thread across a wide range of lengths, in steel Class 14H with plain, black, and zinc plated finishes, and in A2 stainless.

Why Buy From Metric Specialties

As dedicated metric fastener specialists, we hold slotted flat point set screws in the diameters, lengths, and grades that engineers actually need, backed by clear DIN and ISO references so you can specify with confidence. Every item is sourced to recognised standards and quality controlled, giving you consistent thread fit, point geometry, and hardness across repeat orders.

Whether you need a single item for a repair or bulk quantities for production, our range, technical guidance, and fast dispatch help you find the exact fastener for the job. If you are unsure which point style, size, or grade suits your application, our team can help you match the right product to your shaft, load, and environment, so your assemblies hold position and stay serviceable.

Frequently Asked Questions

1. What is a slotted flat point set screw used for?

It locates and clamps a component such as a collar, gear, or pulley on a shaft, or acts as an adjustable stop. The flat point presses against the mating surface without biting into it.

2. What is the difference between a flat point and a cup point set screw?

A flat point bears on the surface without penetrating, so the shaft is left unmarked and the part can be repositioned. A cup point has a sharp annular edge that bites in for a stronger grip, but it marks the shaft and suits permanent settings.

3. Is a set screw the same as a grub screw?

Yes. Grub screw is the common workshop name for a headless set screw of this type. It should not be confused with a metric hex set screw, which in fastener terminology means a fully threaded hex head bolt.

4. What does Class 14H mean?

It is the hardness based property class for set screws defined in ISO 898-5. It indicates the minimum hardness of the screw, which governs how much clamping load the point can transmit without deforming.

5. Should I use a slotted or a hex socket set screw?

Use a slotted screw for modest torque, hand assembly, and where a screwdriver is the tool at hand. Use a hex socket screw where you need higher tightening torque, better tool engagement, or powered assembly.

6. Do I need a flat on the shaft?

It is not required, but a machined flat greatly increases holding power and prevents the screw from riding around a round surface. On a plain round shaft the flat point relies on friction alone.

7. Are slotted flat point set screws available in stainless steel?

Yes. We stock A2 stainless for corrosion resistant applications. Note that stainless is softer than hardened steel, so the safe tightening torque and holding load are lower.

8. How do I stop a set screw from vibrating loose?

Use the correct torque plus a thread locking adhesive, a jam screw fitted above the first, or a nylon patch variant. Vibration is a common cause of collars drifting on a shaft.

9. What sizes do you stock?

We stock M1.6 through M12 in metric coarse thread across a wide range of lengths, in steel Class 14H and A2 stainless.

10. Should the set screw sit flush with the hub?

Yes. A set screw should seat at or below the surface of the hub so nothing protrudes from a rotating part. Choose a length that achieves this while leaving full thread engagement.