9 months by cncdivi

In the world of manufacturing, tapping is a crucial process for creating internal threads in various materials. Two main types of taps dominate the industry: forming taps and cutting taps. But how do you know which one is right for your application? It’s essential to understand their differences, advantages, and limitations to make an informed decision. This blog post will guide you through the intricacies of “forming tap vs cutting tap”, providing valuable insights to help you choose the best tool for your tapping needs.

Short Summary

  • Understanding the differences between forming and cutting taps is essential for selecting the right tap.
  • Forming taps offer increased thread strength and extended tool life, while Cutting Taps provide cost-effectiveness and versatility in material compatibility.
  • Consider factors like lubrication, chamfer types, tap selection & maintenance to achieve successful tapping operations.

Understanding Forming Taps and Cutting Taps

forming tap vs cutting tap

When it comes to creating internal threads, you have two primary options: forming taps and cutting taps. Forming taps, also known as thread forming taps or roll taps, displace material to create threads. Conversely, cutting taps cut material to generate threads. Each type comes with its specific advantages and drawbacks, making them suitable for different applications and materials.

  1. There are four main types of tapping tools – straight flute tap, spiral point tap, spiral flute tap and forming tap.
  2. Each type is used for a different purpose in the tapping process. Roll taps are often chosen over conventional cutting taps for smaller or larger holes, trickier materials like stainless steel or exotic materials, and swarf issues that lead to tap breakage. Understanding the characteristics of forming and cutting taps is crucial for selecting the right tap for your application.

Forming Taps

Forming taps, also known as roll taps, form taps, and fluteless taps, create thread forms by rolling material rather than cutting away any excess material. This means there is no need for flutes to evacuate chips. Thread forming taps generate threads that are significantly more robust than those produced by cutting taps. They offer a long lifespan due to their fluteless design, providing the necessary rigidity to avoid breakage. Additionally, the lack of a cutting edge ensures that there is nothing to wear and become dull. Using a thread forming tap, also known as a roll tap, is an efficient and reliable method for thread forming in various applications.

Lubricant grooves in forming taps enable lubricant to be supplied along the longitudinal axis of the tap, avoiding the creation of a hydraulic seal and “lock” which could otherwise deform or damage the part due to pressure buildup inside the part. This is important because cutting taps produce threads by cutting material, which can cause chips and debris.

Cutting Taps

Cutting taps are tools used to cut material and produce chips. They create internal threads by removing material from the tapped hole. Although thread forming taps are more versatile in terms of material compatibility, cutting taps still offer a wide range of applications.

The use of cutting taps results in chip production, which can impede the tapping process. This makes them less ideal for some applications, such as blind holes, where chips can get trapped and cause issues. However, in many instances, cutting taps are a reliable option for creating internal threads.

Advantages and Disadvantages of Forming Taps and Cutting Taps

When choosing between forming taps and cutting taps, it’s essential to weigh the advantages and disadvantages of each type. Forming taps offer prolonged tool life, increased production efficiency, and chip-free tapping, as well as superior thread quality and compatibility with various materials.

On the other hand, cutting taps provide versatility in material and hole size compatibility and are often more cost-effective. However, they can produce weaker threads and have a shorter tool life compared to forming taps.

Forming Tap Advantages

Forming taps create considerably stronger formed threads compared to cutting taps. This strength comes from the process of displacing material rather than cutting it. The fluteless design of forming taps also contributes to their extended tool life, allowing for faster speeds in the tapping process.

However, forming taps requires larger pre-tap hole sizes. This means that they might not be suitable for all applications, especially those with tight tolerances or specific hole size requirements. Despite this limitation, forming taps remain an excellent choice for applications that prioritize thread strength and tool life.

Cutting Tap Advantages

Cutting taps offer several benefits compared to forming taps, such as the ability to eject chips up and out of the hole, making them particularly useful for blind holes. They are also faster than thread milling and can thread deeper holes in harder materials like steel. Cutting taps are versatile, capable of producing threads in various materials and hole sizes.

The main drawback of using cutting taps is their reduced tool life and the possibility of generating chips during tapping. In applications where thread strength and tool longevity are paramount, forming taps might be a better choice. Nevertheless, cutting taps remain a popular option for their versatility and cost-effectiveness.

Choosing the Right Tap for Your Application

Selecting the right tap for your application is crucial to ensure optimal results. Factors to consider include material compatibility, hole size, and thread quality specifications. By understanding the differences between forming and cutting taps, as well as their respective advantages and limitations, you can make an informed decision tailored to your specific needs.

It’s essential to choose a tap that is compatible with the material being tapped, ensure the hole size is appropriate for the thread size and pitch, and consider the geometry of the tap and the volume of holes to be threaded. By carefully evaluating these factors, you can select the perfect tap for your application.

Material Compatibility

Material compatibility is a critical factor in tap selection, as it determines the required thread pitch and the tap’s compatibility with the home’s water pressure. Forming taps are best suited for use on ductile materials, making them ideal for applications involving soft, non-ferrous metals and moderate steels.  You can form tap up to 36 HRC hardness materials

On the other hand, cutting taps boast versatility and can be employed in a variety of materials. This makes them a more universally applicable option for a wide range of applications, where different materials may be encountered. Understanding the material compatibility of each tap type is essential for successful tapping operations.

Hole Size Considerations

Hole size is another critical factor when choosing a tap. Forming taps requires larger pre-tap hole sizes compared to cutting taps. This means that forming taps may not be suitable for all applications, especially those with tight tolerances or specific hole size requirements.

When selecting a tap, it is crucial to ensure that the hole size is compatible with the thread size and pitch. Choosing the right hole size and tap combination will help guarantee successful tapping operations and high-quality thread production.

Thread Quality Requirements

Thread quality requirements play a significant role in tap selection. Forming taps produce stronger threads due to their process of displacing material, making them an ideal choice for applications that prioritize thread strength. Cutting taps, however, are more versatile and can produce threads in various materials and hole sizes.

The geometry of the tap, the material of the tap, and the volume of holes to be threaded should be taken into consideration when determining thread quality requirements. By assessing these factors, you can select the right tap to meet your specific thread quality needs.

Tips for Successful Tapping Operations

tapping fluid lubricant

To ensure successful tapping operations, it’s essential to follow best practices and consider factors such as proper lubrication, understanding chamfer types, and tap selection and maintenance. By adhering to these guidelines, you can maximize tool life, minimize potential issues, and achieve optimal results in your tapping operations.

In the following sections, we’ll delve deeper into these key factors and provide practical tips to help you achieve successful tapping operations, regardless of whether you’re using forming or cutting taps.

Lubrication and Cutting Oils

Lubrication and cutting oils play a crucial role in minimizing friction and heat generation during tapping operations. Proper lubrication can significantly extend the life of your tap, ensuring smooth and efficient threading.

For optimal tap performance, it is typically recommended to use straight cutting oil. For non-ferrous and non-metallic materials, a coolant or cutting fluid (light oil or soluble oil) is suggested. Additionally, for cold forming taps, a cutting oil or lubricant is preferable to a coolant. Ensuring proper lubrication is essential for successful tapping operations.

Chamfer Types and Their Importance

Chamfer types play a significant role in tapping operations. They determine how cutting action is distributed and should be chosen based on the hole type. The three most frequently used chamfer types are taper, plug, and bottoming.

The type of hole should be taken into account when selecting a chamfer type. Understanding the role of chamfer types in the tapping process and selecting the appropriate type for your application can greatly impact the success of your threading operations.

Proper Tap Selection and Maintenance

Proper tap selection and maintenance are crucial for maximizing tool life and ensuring successful tapping operations. To achieve this, it’s important to use the correct tapping speed (10 to 13 SFM), provide adequate and appropriate lubrication, and apply the correct amount of pressure.

Furthermore, tap holders with torque settings should be employed, and the suitable lubricant should be chosen based on the material being tapped. By following these guidelines, you can ensure that your tap is suitable for the intended use and is properly maintained to ensure its durability.

Real-World Applications of Forming Taps and Cutting Taps

Forming and cutting taps have practical applications in various industries and materials. Forming taps are often employed when traditional cut tapping is not feasible, such as tapping blind holes and ductile materials. Their ability to create strong, chip-free threads makes them ideal for these specific situations.

On the other hand, cutting taps, also known as cut taps, are utilized for producing internal threads efficiently and cost-effectively. Their versatility allows them to be used in a wide range of materials and hole sizes, making cut taps a popular choice for many applications.

Understanding the strengths and limitations of each tap type can help you make informed decisions for your real-world tapping needs.

Summary

In conclusion, understanding the differences between forming taps and cutting taps is essential for selecting the right tool for your tapping needs. By considering factors such as material compatibility, hole size, and thread quality requirements, you can make informed decisions that will improve the success of your tapping operations. Whether you choose forming taps for their strength and efficiency or cutting taps for their versatility, understanding their respective advantages and limitations will ensure you achieve optimal results in your real-world applications.

Frequently Asked Questions

 

Forming taps are perfect for tapping blind holes and cutting threads in materials of less than 36HRC hardness.  They feature special lubrication grooves that reduce friction, ensure clean thread cutting, and produce no chips.

The key distinction between roll form and cut tap strength is that roll taps use the material itself to create a thread, whereas cutting taps physically remove material to achieve the same result.  This results in cut taps being the more precise option, but also leaving them more vulnerable to breakage under pressure.

See our article on 10 different kinds of taps for more information on this.

Threading and tapping are two different processes used to create threads on a surface.  Thread milling is a third process for creating threads.

 

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