How to Use a Tap and Die Set


If you’re a DIY enthusiast, mechanic, or craftsman, a tap and die set is an invaluable tool for threading and re-threading various materials. With this set, you can create internal threads using a tap or external threads using a die on various materials such as metal, wood, plastic, and more. However, when faced with a collection of scattered accessories, you may find yourself questioning: How to use a tap and die set?

Understand Taps and Dies

A Tap and Die Set is a compilation of instruments employed for cutting, cleansing, and restoring threads on nuts, bolts, and screws. It comprises two primary elements: taps and dies. Taps are utilized to form threads inside a hole, while dies are employed to create threads on the external surface of a cylindrical object. These tools are available in different sizes and are crafted from top-notch materials such as high-speed steel or carbon steel. They are going to be introduced in the following paragraphs.

Essentials of Taps and Dies

There are several factors to consider when selecting the appropriate set for your needs. Let’s delve into each factor and provide examples to guide you in making the right choice.

Factors to Consider



– Carbon Steel: Suitable for general-purpose use.
– Alloy Steel: Provides increased strength and wear resistance.


A comprehensive tap and die set typically includes sizes ranging from M3 to M12 for metric threads and 1/4″ to 3/4″ for SAE threads, covering a wide range of applications in various industries.

 Thread Type

Metric Threads: Metric threads are prevalent in European countries and other parts of the world using the metric system. They are measured in millimeters and come in different pitches for fine or coarse threads.
– Unified Thread Standard (UTS): Also known as the American National Thread, UTS is the standard thread used in the United States for general applications. It is measured in inches and categorized into threads per inch (TPI).


 General-Purpose Set: Suitable for everyday repairs and tasks.
– Specialized Set: Designed for specific industries like automotive or plumbing.

Storage Case

A strong case is essential for preventing rust, corrosion, and impact damage during storage or transportation of the tap and die set.

Now, when everything is ready, time to properly use the tap and die set. Prior to commencing the threading process, it is essential to ascertain the number of TPI. This information is crucial for selecting the appropriate tap and/or die that matches the bolt, nut, or hole. Fortunately, most tap and die sets come equipped with a gauge (as photo below shown) that aids in this determination. These gauges typically consist of several different “blades” that assist in identifying the correct TPI for a given bolt or nut.

gauge of tap and die set

How to Use a Tap and Die Set- Create Threads

Tapping Process Guide

Step 1: Drilling the Hole

Before you begin tapping, ensure that the hole is properly drilled to the correct size for the desired thread. Use a suitable drill bit that matches the tap size you intend to use. To avoid drill bit breakage and ensure smoother drilling, apply cutting oil to the hole as a lubricant.

Step 2: Selecting the Right Tap

Consider the material, thread type, and size of the hole when selecting the tap. For general applications, a hand tap is commonly used. For more specialized projects or tough materials, consider using spiral point taps for through-holes or spiral flute taps for blind holes.

Step 3: Applying Cutting Fluid

Applying cutting fluid helps reduce friction, heat, and tool wear while improving the thread’s surface finish. Cutting fluid also aids in chip evacuation, preventing clogging and improving the efficiency of the tapping process.

Step 4: Aligning the Tap

Position the tap perpendicular to the workpiece and ensure it is centered correctly over the hole. Hold the tap firmly but avoid using excessive force during this step. Using a tap wrench or a tap handle provides better control and prevents any accidental tilting that may lead to misaligned threads.

Step 5: Starting the Tapping

Start turning the tap clockwise with gentle pressure. As the tap begins to cut, maintain a steady and even rotational speed. For tougher materials, use a slower rotational speed to prevent the tap from breaking and to ensure a clean and accurate thread.

Step 6: Backing Off Periodically

Periodically reverse the tap counterclockwise, known as “backing off,” to break the chips and clear the tap. This step helps prevent chip accumulation and thread damage.Backing off also allows the cutting fluid to reach the cutting edges, reducing heat build-up and extending the tap’s lifespan.

Threading Process Guide

The threading process involves using a die to create external threads on cylindrical objects like bolts or rods.

Step 1: Choosing the Right Tap

As usual, the first step is to select the appropriate die that matches the desired thread size and type.

Step 2: Secure the Workpiece

Place the rod or bolt securely in a vise, ensuring that the section you intend to thread remains exposed and accessible.

Step 3: Apply Cutting Fluid

Before initiating the threading process, apply cutting fluid to the area you’ll be threading. This helps reduce friction and heat, extending the life of the die and ensuring smoother threading.

Step 4: Align the Die

Position the die squarely on the workpiece, making sure it is perpendicular to the surface. Begin turning the die clockwise while exerting steady pressure. Keeping the die straight is crucial for producing even and precise threads.

Step 5: Back Off Periodically

Similar to tapping, it is essential to periodically reverse the die’s rotation slightly. This action breaks the chips that form during the cutting process and prevents them from hindering the threading process.

Step 6: Check the Threads

At regular intervals, use a thread gauge to check the quality and accuracy of the threads. This step is crucial to ensure that the threads meet the required specifications.

How to use tap and die set- Repair Threads

Repairing Cross-threaded Bolts

  1. Secure the Bolt in a Vise: Start by securely clamping the bolt in a vise. To avoid further damaging the threads, it is recommended to clamp only the head of the hex bolt. If clamping the shaft becomes necessary, consider using one of the following methods to protect the bolt threads:
    1. Use a couple of blocks of wood.
    2. Place a piece of rubber, like a bicycle inner tube, in the vise jaws.
    3. Use two pieces of leather.
  2. Align the Die and Begin (Re)Cutting the Threads: Apply a small amount of cutting oil to lubricate the die and keep it cool during the process. Take advantage of the open top in most taps and die wrenches to add lubricant without removing the die, which will also prolong the lifespan of your tap and die set. To learn more about
  3. While threading the die down onto the bolt, it will quickly catch the existing threads. Occasionally, you may need to back the die out a bit to clear the threads and facilitate better cutting. This is normal and akin to drilling into wood with a large bit. Once the die reaches a point where the bolt protrudes from the top, the process is complete.

Rethreading Holes and Nuts

Threading or re-threading a nut using a tap is a straightforward process. Follow these steps:

  1. Secure the Nut in a Vise: Begin by securely clamping the nut in a vise.
  2. Use a Gauge to Find the Right Size Tap: If you don’t have a matching bolt, utilize a gauge to determine the correct size tap for the nut or hole you intend to thread. For threading a nut independently, it’s best to use the actual matching bolt to set the size. This prevents the need to force the gauge into a worn-out bolt, which might be challenging or impossible depending on its condition.
  3. In case the threads are severely damaged, you can always drill out the hole and re-tap it to accommodate a slightly larger bolt. Alternatively, you may choose to fill the hole and re-tap it.
  4. Secure the Tap and Begin Threading: Insert the tap into the provided wrench and secure it. Next, place the tap into the nut and begin turning it down by hand, making sure to keep it perfectly aligned with the hole. Just like when using a die, using cutting oil is essential. Regularly back the tap out to remove debris that accumulates in the threads during the threading process.

It is important to note that most tap and die sets for rethreading use round dies, which typically require 2 to 5 screws for securing, making the process time-consuming and effort-intensive. To address this issue, toolant has developed a specialized hexagonal die for rethreading in 127pcs SAE/Metric Ratcheting Tap and Die Set. Unlike the more common round dies, the hexagonal design offers simplicity as it eliminates the need for screws to lock it in place. This design provides better stability during the rethreading process, preventing slippage. The hexagonal die requires only one screw to be tightened, making the rethreading task more efficient and user-friendly.

hexagonal die for rethreading

In addition, compared to regular wrenches, toolant’s reversible ratcheting T handles offer distinct advantages. With one-way rotation and efficient transmission, these ratcheting wrenches provide users with easy control over rotation direction and speed, allowing for greater force with minimal effort. The toolant ratcheting wrench, featuring a 5° swing arc and a reversing lever, eliminates the need for hand-over-hand turning. Besides, its twist lock guide system reduces the “walk back” of the die guide, ensuring the dies stay centered during cutting.

I take immense pride in being an accomplished woodworker, a dedicated researcher, and an expert in the realm of home improvement tools and tool accessories. With years of hands-on experience, my passion for craftsmanship and innovation runs deep within me. I have honed my skills through countless hours of practice, mastering the intricacies of woodworking techniques. Through my unwavering commitment to excellence, I have become a trusted authority in the field. Clients and colleagues alike rely on my expertise, knowing that I am a reliable source of knowledge and guidance. The satisfaction of seeing my clients' visions come to life fuels my drive to continually push the boundaries of creativity and precision. My work serves as a testament to my unwavering dedication, attention to detail, and relentless pursuit of perfection. Whether it's selecting the perfect tool for a specific task or delving into the nuances of power tool accessories, I immerse myself in every aspect of my craft. Being both an experienced handyman& contactor, and a meticulous researcher allows me to bring a unique perspective to my work. I am constantly exploring new techniques, staying up-to-date with the latest advancements, and seeking out innovative tools and accessories that can elevate the art of woodworking to new heights. With unwavering enthusiasm, I am eager to share my knowledge and expertise with others who share the same passion. Together, we can embark on a journey of creativity, craftsmanship, and self-expression, pushing the boundaries of what is possible in the world of tools.

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