Different Types of Thread Taps – A Comprehensive Guide

When it comes to creating internal threads in metal components, choosing the right type of thread tap is crucial. But with so many variations available, how do you know which tap is best for your specific application?

This comprehensive guide will help you understand the different types of thread taps, their features, advantages, disadvantages, and recommended uses. Let’s dive in.

What is a Thread Tap?

Thread Tap Definition:
A thread tap—also known as a screw tap—is a tool used to cut or form internal threads in a workpiece. These grooves are aligned along the axis and allow bolts or screws to be fastened into metal components.

Thread taps are typically made of high-speed steel (HSS) or carbide, and can be used for both manual tapping and machine-assisted tapping. Due to their simplicity and versatility, taps are essential tools in any workshop for producing small to medium-sized internal threads.

Why Choosing the Right Thread Tap Matters

Tapping is a demanding process because the tool is almost entirely buried in the workpiece. The cutting load per tooth is high, and the tap must manage chip removal effectively. This makes selecting the correct tap critical for performance, tool life, and final thread quality.

Types of Thread Taps

Thread taps can be classified based on various criteria:

1. By Operation Method:

• Hand Taps: For manual tapping; made of carbon or alloy tool steel.

• Machine Taps: For use on machines; made of high-precision HSS or carbide.

2. By Manufacturing Principle:

• Cutting Taps: Remove material to form threads.

• Forming Taps: Displace material to form threads without cutting.

3. By Thread Type:

• Metric Thread Taps

• Metric Fine Thread Taps

• Pipe Thread Taps

4. By Design:

• Straight Flute Taps

• Spiral Flute Taps

• Spiral Point Taps

• Forming Taps

5. By Standard:

• DIN, ISO, JIS, ANSI

6. By Material:

• HSS Taps

• Cobalt Alloy Taps

• Carbide Taps

Let’s explore the most common types of thread taps in detail:

1. Straight Flute Taps

Overview

The most commonly used type, straight flute taps are ideal for general-purpose tapping.

Key Features

• Made from HSS or carbide

• Commonly available in 2, 4, or 6 cutting edges

• Suitable for both through and blind holes

Advantages

• Simple structure and affordable

• High rigidity

• Versatile for many materials and machines

Disadvantages

• Poor chip removal

• Less suitable for ductile materials like stainless steel

• Not ideal for deep holes

Applications

• Best for threading hardened steels, cast iron, and standard metal parts

• Works well on lathes, drill presses, and tapping machines

2. Spiral Flute Taps

Overview

Designed primarily for blind holes, these taps use spiral grooves to lift chips out of the hole.

Key Features

• Right-hand or left-hand spiral options

• Common helix angles: 15°–45°

• Excellent chip evacuation

Advantages

• Longer tool life

• Great for deep or blind holes

• Effective chip removal

• Smooth cutting and reduced torque

Disadvantages

• Less suitable for large-size threads

• Higher cost than straight flute taps

Applications

• Ideal for ductile materials (e.g., stainless steel, aluminum)

• Best for blind hole tapping in CNC machining

• Commonly used for M3–M36 sizes

3. Spiral Point Taps (Gun Taps)

Overview

These taps have a modified cutting edge that pushes chips forward, making them ideal for through holes.

Key Features

• Straight flutes with a pointed cutting lead

• Pushes chips out ahead of the tool

Advantages

• Fast cutting speed

• Excellent thread quality

• High strength and durability

• Less chip entanglement

Disadvantages

• Not suitable for blind holes

Applications

• Perfect for through-hole tapping

• Suitable for ferrous and non-ferrous metals, including stainless steel

4. Forming Taps (Roll Taps)

Overview

Unlike cutting taps, forming taps use material deformation to create threads—no chips are produced.

Key Features

• No flutes; solid body

• Relies on material plasticity

• Requires pre-hole with accurate diameter

Advantages

• High-strength threads

• No chip clogging

• Smooth thread surface

• Long tool life

Disadvantages

• Not suitable for hard materials

• Threads may have surface grooves—unsuitable for fluid sealing

Applications

• Best for aluminum, copper, soft steels

• Ideal for applications requiring clean and strong threads

• Suitable for blind or through holes

Thread Tap Materials

The material of the tap determines its cutting ability and lifespan:

Conclusion

Choosing the right thread tap depends on:

• Material of the workpiece

• Hole type (blind vs through)

• Production volume

• Required thread strength and accuracy

Whether you’re working with standard steel, non-ferrous metals, or high-hardness alloys, selecting the correct tap type—straight flute, spiral flute, spiral point, or forming tap—will significantly improve performance and thread quality.