The threading technique is crucial in manufacturing. A thread tap carefully carves the threaded segments of metal connectors. This method is widely used, especially in sectors like aerospace and electronics, where threaded holes are crucial to assembling components tightly.
Continuing to read, you’ll discover the practical applications of various tap types and how they can impact your project’s success.
What is a thread tap?
Thread taps are precision tools that create internal threads in pre-drilled holes. This allows bolts and screws to be inserted into the hole, then tightened. Taps are essential for assembling mechanical parts requiring bolted or glued connections. It is essential to many products and infrastructure’s structural integrity and functionality.
Components of Tap
The tap is an intricately designed tool that has several key components. Each component serves a specific purpose during the tapping process.
Body
The tap’s main body contains the threads. The tap fits into pre-drilled holes, cutting threads on the hole’s interior surface to match its pattern.
Shank
The shank is that section of the tap at the top held by the tapping machine. This is crucial to ensure the tap is aligned and held correctly during threading.
Tang
The small tapered end on the bottom of the shank pushes the tap into its holder. The tang is a small part that plays an important role in transferring rotational force from the shank to the tap.
Flutes
The longitudinal grooves are cut into the tap’s body. They remove chips from the cutting area, prevent clogs, and ensure clean cuts.
Land
The uncut part of the tap’s body between the flutes is called the land. It stabilizes the tap and ensures accuracy during cutting.
Heel
The heel is where the tap threads trail off. The tap is angled to make it more accessible to remove from the material and reduce the risk of damaging the newly formed threads.
Cutting Face
The tap’s cutting face does the actual cutting. It is precisely shaped and inclined to cut the material and form accurate threads efficiently.
Types of taps
Selecting the right tap is essential in the manufacturing world at Shengen. We use a variety of taps for different applications.
Hand Taps
The most common taps used in manual threading are hand taps. The taps come in three-piece sets: plug, bottoming, and taper. Each one serves a different stage of the tapping process.
Taper Tap
The diameter of a taper tap increases gradually. The tapered design makes it easy to create the first threads.
Plug Tap
The plug tap is a smaller version of the taper. You use the plug tap to deepen threads.
Bottoming Tap
The bottoming tap is almost without a taper. The bottoming tap finishes threading in blind holes that the plug and taper taps have started.
Master Tap
The master tap is an extremely precise tap used to create threads that are used as standards for measuring other threads. Precision and consistency are key.
Gas Tap
Gas taps have been designed specifically for threading gas fittings, ensuring airtight connections. They are also designed to meet the unique requirements of gas lines.
Machine Tap
Operators can use machine taps in lathes or drilling machines. They are designed to thread at high speeds in various materials and are more durable.
Machine Screw Tap
This type of tap serves to thread machine screws. These taps are smaller, and they have a specific thread pattern that fits machine screw standards.
Extension Tap
Standard taps cannot reach deep holes or other difficult threading holes, but extension taps are designed to do this.
Bend Shank Tap
The bend shank taps are designed with a curved shank to allow threading in areas with limited access, or the machine spindle cannot reach.
Stay Bolt Tap
Stay bolt taps can be used to thread stay bolts. These are integral components of certain boilers and pressure vessel types.
Spiral Fluted Tap
The spiral-fluted taps, designed with helical flutes to help evacuate chips upwards, are perfect for blind holes made of soft materials.
Fluteless Tap
Fluteless tappings (roll or form taps) do not cut the threads. Instead, they form them by displacing material. This produces stronger threads and can be used on materials that have difficulty removing chips.
How do you skillfully use a tap to thread?
To create perfect threads, follow these guidelines to achieve the highest quality.
Clamping Process
It is essential to secure the workpiece before drilling or tapping. Correct clamping will prevent any movement that could affect the quality of your results. Here are some tips to help you ensure a safe setup:
- Remove all debris by thoroughly cleaning the workpiece.
- Position the workpiece in the middle of the jaws. Use direct clamping for large workpieces on the workbench.
- Use caution when clamping the workpiece to avoid damaging it.
Drilling Operation
Attention to detail is required when drilling the perfect hole:
- Mark the area you intend to drill with a pencil. This will outline a circle.
- Apply a suitable lubricant before drilling to improve performance. Drill a cylinder hole with a drill bit best suited to the material, using steady pressure and speed.
- Use a drill with a powerful motor to straighten the hole.
- To accommodate threading expansion, the diameter of the hole should be smaller than the size of the bolt. A standard chart can be used to match the bolt size and the hole diameter.
Please take extra care when drilling blind holes. Ensure the hole depth is slightly greater than the bolt length.
Tapping Operation
Taping holes requires precision and care.
- Choose the correct tap and attach it to a tapping handle or device for automated operations.
- Apply lubricant directly into the hole and onto the tip of the tap to ensure smooth threading.
- Align the tap carefully with the hole and apply gentle pressure until you meet resistance. After every 360-degree rotation clockwise, turn 180 degrees counterclockwise. This is important for breaking the chips and clearing the way for the tap to cut uninterrupted.
Choose the Right Tape for Your Project
The market offers many different types of taps. We consider the factors that affect our decision when choosing the right tap for any project.
Type of Workpiece
Our starting point is the workpiece’s material. Taps are required for different materials, ranging from soft plastics and steel to hardened metals. More complex materials require taps made of robust materials such as cobalt and carbide. Softer materials can be used with high-speed stainless steel taps.
Tap Material
When choosing the material for the tap, it is important to match the tap’s durability and hardness with the workpiece’s material. When working with stainless steel or other abrasive materials, we choose taps that have coatings such as Titanium Nitride to increase the tool’s life and performance.
Types of Holes
Our choice of tap is influenced by whether we are using blind or through holes. Spiral point taps excel in creating threads through holes by moving chips forward, thus preventing clogging. For blind holes, where chip evacuation poses a challenge, spiral flute taps are the better option. They pull the chips out and back into the hole.
Cutting Speed
When selecting a tap, the cutting speed is crucial. Different materials and tap designs can handle different speeds. Taping in aluminum, for example, can be done faster than tapping in steel. The material and design of the tap, as well as the lubricant used, will determine the best speed to thread without causing tap breakage.
At Shengen, we are always exploring new topics related to tapping in our quest for efficiency and precision. These areas enhance our capabilities and ensure that we remain at the forefront of manufacturing innovation.
Coating Technologies for Taps
Coatings like Titanium Nitride, Titanium carbo nitride, and Aluminum Titanium Nitride can significantly increase taps’ thermal resistance and hardness. This allows us to work with harder materials and extend the taps’ life.
Troubleshooting common tapping issues
Problems like premature wear and thread quality can stop production and impact product quality. Our expertise has helped us identify the root cause of these issues, including incorrect tap selection, incorrect feed and speed rates, and insufficient lubrication. By addressing these issues quickly and effectively, we can minimize disruptions and maintain our standard of excellence.
Care and Maintenance for Taps
After each use, cleaning the taps regularly and inspecting them for damage or wear is essential. Store taps in an organized, dry environment to prevent corrosion and physical damage. We recommend applying a thin oil coating to the taps to prevent rust before storing them.
Determine Your Thread Tap Size Using This Guide
Various types of taps are available to accommodate different threading needs across a myriad of sizes. The crucial factor in selecting the proper size tap is the diameter of the pre-drilled hole. Should the drilling tool be more significant than necessary, it will result in threaded holes too wide for the intended fastener. Conversely, drilling with a too small tool leaves insufficient room for the tap, risking damage to both the tap and the component.
Tapping Process
Adjusting the hole size post-drilling through the tedious process is an effective strategy to circumvent these issues. To precisely calculate the needed drill size for a perfect fit with your tap, refer to the following standard equation:
Drill Size Calculation:
Drill Size=7/8(size of the tap) – 1/32
The Chart for Thread Tap Size Determination
| Tap size | Major Diameter (mm) | mm per thread | Drill Size (mm) |
|---|---|---|---|
| M1.6 * 0.35 | 1.6mm | 0.35 | 1.25mm |
| M2 * 0.4 | 2mm | 0.4 | 1.6mm |
| M2.5 * 0.45 | 2.5mm | 0.45 | 2.05mm |
| M3 * 0.5 | 3mm | 0.5 | 2.5mm |
| M3.5 * 0.6 | 3.5mm | 0.6 | 2.9mm |
| M4 * 0.7 | 4mm | 0.7 | 3.3mm |
| M5 * 0.8 | 5mm | 0.8 | 4.2mm |
| M6 * 1 | 6mm | 1 | 5mm |
| M8 * 1.25 | 8mm | 1.25 | 6.8mm |
| M8 * 1 | 8mm | 1 | 7mm |
| M10 * 1.5 | 10mm | 1.5 | 8.5mm |
| M10 * 1.25 | 10mm | 1.25 | 8.8mm |
| M12 * 1.75 | 12mm | 1.75 | 10.2mm |
| M12 * 1.25 | 12mm | 1.25 | 10.8mm |
| M14 * 2 | 14mm | 2 | 12mm |
| M14 * 1.5 | 14mm | 1.5 | 12.5mm |
| M16 * 2 | 16mm | 2 | 14mm |
| M16 * 1.5 | 16mm | 1.5 | 14.5mm |
| M18 * 2.5 | 18mm | 2.5 | 15.5mm |
| M18 * 1.5 | 18mm | 1.5 | 16.5mm |
| M20 * 2.5 | 20mm | 2.5 | 17.5mm |
| M20 * 1.5 | 20mm | 1.5 | 18.5mm |
Conclusion
A thread tap precisely forges internal threads within the apertures of components, facilitating the insertion of fasteners where traditional bolts and nuts fall short. To achieve this, manufacturers use different types of taps, each tailored to thread-specific drilled openings. Through numerous tapping techniques, customization of parts is achieved, allowing for a tailored fit in diverse applications.
Do you need a reliable sheet metal parts manufacturer? Shengen is the place to go. We specialize in sheet metal laser cutting, bending, surface finish, and sheet metal welding. Reach out to Shengen Today and seek help from professionals!
FAQs:
Can you use the same tap on different materials?
Using the same tap on different materials is only sometimes recommended. The hardness and abrasiveness of different materials can impact a tap’s performance and life expectancy.
When should I replace my tap?
When you see signs of wear, it is time to replace the tap. It is essential to inspect your tap regularly. If creating new threads becomes difficult or you need to apply more force to turn the tap, this may signal that the tap is worn out and needs replacement.
What is the sign of a poorly-threaded hole?
Cross-threading, uneven or incomplete threads, and too shallow or deep threads are all signs of a poorly tapped hole. Fasteners not threaded correctly can fail under pressure or do not fit properly.
Can damaged threads be repaired?
Damaged threads are often repairable. The extent of damage will determine the method. A thread repair kit can restore threads by inserting a helical spiral.
What is the difference between machine and manual tapping?
Manual tapping is best for small-volume projects or when you need to feel and control the material. Machine tapping is the best choice for high-volume production or when accuracy and speed are critical. When choosing the right tap, consider the specifics of your project, like the number of holes you need to tap and the equipment at your disposal.
More Resources:
Comparison of manual versus machine tapping – Source: Mandmsales
Art of precise drilling – Source: Linkedin
Tapping and Cleaning Threaded Holes – Source: Kangamotorsports
Hey, I'm Kevin Lee
For the past 10 years, I’ve been immersed in various forms of sheet metal fabrication, sharing cool insights here from my experiences across diverse workshops.
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Kevin Lee
I have over ten years of professional experience in sheet metal fabrication, specializing in laser cutting, bending, welding, and surface treatment techniques. As the Technical Director at Shengen, I am committed to solving complex manufacturing challenges and driving innovation and quality in each project.
