Tap Size Drilling Chart

Tap Size Drilling Chart

Tap size drilling charts are pivotal tools in the engineering and manufacturing sectors, ensuring product precision and uniformity. This guide delves into the intricacies of the Tap Size Drilling Chart, particularly highlighting a common issue many face: Flash in Injection Molding.

Grasping the causes and learning effective control methods for flash is essential, as it directly influences the quality and reliability of the final product. Readers can significantly enhance their production efficiency and product quality by understanding this topic.

Dive in to explore the technical nuances and gain insights that can shape your molding projects for the better.

Thread SizeDrill Diameter (mm)Tap Drill Size
Coarse Thread
1-64.0595No. 53
2-56.0700No. 50
3-48.0785No. 47
4-40.0890No. 43
5-40.1015No. 38
6-32.1065No. 36
8-32.1360No. 29
10-24.1495No. 25
12-24.1770No. 16
1/4-20.2010No. 7
Fine Thread
1-72.0595No. 53
2-64.0700No. 50
3-56.0820No. 45
4-48.0935No. 42
5-44.1040No. 37
6-40.1130No. 33
10-32.1590No. 21
12-28.1820No. 14
1/4-28.2130No. 3
Table:Tap and Drill Size Chart

Check Out: Types of Drill Bits Used in Part Manufacturing

What is Flash in Injection Molding?

In injection molding, ‘flash‘ is an anomaly that professionals often grapple with. Flash refers to the thin material layer that seeps out of the mold cavity, settling along the mold’s parting line or ejector pins.

In essence, the excess plastic inadvertently extends beyond the intended product boundary, leading to unwanted protrusions on the final piece.

Factors to Consider:

Several factors can contribute to flash, ranging from an overfilled mold cavity to an aged, worn-out mold that no longer seals perfectly. Regardless of the cause, the moment is undesirable, as it affects the final product’s aesthetics and function and often requires additional labor for removal.

When flash occurs, it often demands post-molding processes, such as trimming or deflashing, to ensure the product meets its specifications.

These extra steps add to production costs and can jeopardize the part’s structural integrity if not addressed correctly.

Understanding the phenomenon of flash is paramount for anyone involved in injection molding. The implications of flash extend beyond mere aesthetics; they touch on efficiency, cost, and product quality.

By comprehending what flash is, professionals can be better equipped to prevent its occurrence and ensure a smoother production process.

Read Out: What is Injection Molding? Definition, Processes, Applications

The Main Causes of Injection Molding Flash:

The Main Causes of Injection Molding Flash

1. Mold Flash During the Injection Phase:

The injection phase is the initial and crucial stage where the molten plastic is injected into the mold cavity. During this phase, mold flash can occur for several reasons.

The foremost cause is the injection pressure pushing the molten material past the intended mold boundaries. High temperatures can also make the plastic too fluid, causing it to seep through the minor gaps.

 Another contributing factor is the incorrect alignment or wearing out of mold components. When the mold halves don’t align perfectly or have been eroded over time, it provides avenues for the material to escape, resulting in flash.

Ensuring optimal injection parameters and maintaining mold conditions can mitigate this mold flash.

2. Mold Flash During Packing or Holding:

Mold Flash During Packing or Holding

Once the molten plastic is inside the mold, the packing or holding phase begins, ensuring the material occupies every part of the mold cavity uniformly.

During this phase, mold flash can emerge from excessive packing pressure. If the pressure remains too high while the plastic solidifies, it can force the material out of slight gaps, leading to flash.

Additionally, prolonged holding times can cause the material to creep into areas it shouldn’t. Monitoring and calibrating the machine’s settings regularly to prevent these issues is essential, ensuring that the packing pressure and holding time are optimal for the specific material and mold.

3. Mold Flash During the Process Due to Flow Characteristics:

The inherent flow characteristics of the plastic material play a significant role in mold flash. Some plastics have a high viscosity, while others flow more freely. When using a material with low viscosity or particularly reactive to changes in temperature, there’s a higher risk of flash.

Variations in flow rate, coupled with complex mold designs with thin walls or intricate details, can create areas where the plastic flows too aggressively, resulting in flash.

Professionals must understand the flow characteristics of their materials and adjust processing conditions accordingly. This might involve tweaking temperature settings, altering flow rates, or choosing a material better suited to the mold design.

By recognizing these causes and adjusting the injection molding process accordingly, professionals can reduce the occurrence of flash, leading to better-quality products and more efficient production.

Learn More: Injection Molding Flash: Top 9 Causes and How to Solve Them

5 Effective Ways to Control Flash in Injection Molding:

1. Design for Manufacturability:

Design for Manufacturability

An ounce of prevention is worth a pound of cure. By integrating manufacturability considerations during the design phase, many molding complications, including flash, can be anticipated and avoided. Design for Manufacturability (DFM) entails creating parts optimized for production.

It emphasizes simplifying designs, avoiding overly thin or intricate sections, and ensuring uniform wall thickness.

Consistency in design can prevent areas where flash is more likely to occur due to uneven material flow. Furthermore, incorporating proper draft angles and robust parting lines in the mold design ensures that the molten plastic flows smoothly, fills the cavity correctly, and the mold parts fit snugly to prevent flash.

Read More: Role of Design in Manufacturing through Injection Molding: A Detailed Guide

2. Slow Down the Injection Rate:

2. Slow Down the Injection Rate

The rate at which molten plastic is injected into a mold directly impacts the likelihood of flash. An aggressive injection rate can force the plastic to escape through the slightest gaps, causing flash.

Slowing down this rate ensures the material fills the cavity more gently and uniformly, significantly reducing the potential for flash.

Regularly monitoring and adjusting the injection speed based on the material and mold complexity is vital. While it might slightly increase the cycle time, the benefits of reduced defects and post-processing outweigh the minor delay.

3. Specify a Flash-Free Mold:

Specify a Flash-Free Mold

With advancements in manufacturing technologies, flash-free molds have become a reality. These molds are precision-engineered to ensure the tightest possible fit between mold components, leaving no room for unwanted plastic seepage.

Opting for flash-free molds can be particularly beneficial for high-volume production runs where consistent quality is paramount.

While they might entail a higher initial investment, the long-term savings regarding reduced defects and post-molding processes can be substantial.

4. Proper Mold Cleaning:

Proper Mold Cleaning

Over time, residues from the molten plastic, lubricants, and other contaminants can accumulate in the mold, especially along the parting lines. These residues can prevent the mold from closing tightly, paving the way for flash.

Regular and thorough mold cleaning ensures no foreign materials interfere with its precision fit. Techniques like ultrasonic cleaning and abrasive blasting can ensure the mold remains free of residues, guaranteeing flash-free production.

5. Proper Mold Maintenance and Process Improvements:

Proper Mold Maintenance and Process Improvements

Molds, like any equipment, wear down over time. Regular maintenance, such as checking for signs of erosion or damage and ensuring the mold remains perfectly aligned, can drastically reduce flash occurrence.

Moreover, a continuous improvement process involving regular evaluations and adjustments to the molding process can help identify potential flash causes.

By adopting a proactive approach and staying updated with the latest techniques and materials, manufacturers can consistently enhance the quality and efficiency of their production runs.

Incorporating these strategies can significantly diminish the occurrence of flash in injection molding, ensuring that the final products meet the highest standards of quality and consistency.

Check Out: Plastic Injection Molding Lifespan: How Long Do Injection Molds Last?

A Skilled Partner Can Help Your Injection Molding Project:

A Skilled Partner Can Help Your Injection Molding Project

In the intricate domain of injection molding, where precision and expertise are paramount, the significance of partnering with a seasoned professional cannot be overstated.

By having a skilled partner on your side, you can ensure that every facet of your injection molding project meets the highest industry standards, from design to the finished product.

Industry Insight and Experience:

Industry Insight and Experience

A skilled partner comes equipped with years of industry experience. They’ve encountered many challenges and developed solutions over time, ensuring a smoother path for your projects.

Such expertise can be invaluable, especially when navigating complex molds or challenging materials.

By anticipating potential problems and offering tried-and-tested solutions, a seasoned partner can significantly reduce the trial-and-error process, saving time and resources.

Advanced Tools and Technologies:

Advanced Tools and Technologies

The world of injection molding is ever-evolving, with new techniques, materials, and technologies emerging regularly. A dedicated partner is always at the forefront of these advancements.

By leveraging the latest tools and tech, they can ensure that your project benefits from the most efficient and advanced methodologies available, resulting in superior product quality and faster turnaround times.

Consistent Quality Control:

Quality Control

Quality is paramount in injection molding. Even the slightest inconsistencies can lead to product malfunctions or reduced lifespan.

A skilled partner employs rigorous quality control processes, ensuring every product from the mold aligns perfectly with the specified parameters. This dedication to quality guarantees product reliability and reduces wastage and post-production corrections.

Strategic Collaboration:

Strategic Collaboration

A seasoned partner doesn’t merely execute your project—they collaborate with you. From understanding your objectives to brainstorming design ideas and optimizing the manufacturing process, a collaborative approach ensures the final product is in sync with your vision and goals.

This strategic partnership can be invaluable in refining product design, reducing costs, and enhancing overall efficiency.

Continual Learning and Adaptation:

Continual Learning and Adaptation

The best partners in the injection molding industry view every project as a learning opportunity. By continually refining their techniques, evaluating outcomes, and adapting to new challenges, they ensure that their methods are always at the cutting edge of the industry.

While the benefits of having a skilled partner are numerous, choosing one with a proven track record and dedication to excellence is essential. For those seeking unparalleled expertise and a collaborative approach to their injection molding projects, Kemal stands as a beacon.

With a rich legacy in the industry and an unwavering commitment to quality, Kemal can be the difference between a good project and a great one.

If you’re serious about elevating the standards of your injection molding projects, contact us to get insights, solutions, and partnerships that can transform your endeavors. Remember, the right partner can make all the difference in precision manufacturing.


Navigating the intricate landscape of injection molding demands expertise, precision, and a commitment to quality. Understanding the nuances of mold flash and employing strategies to combat it are essential steps toward perfection. But how can one ensure consistent quality and efficiency?

How can we drive innovation while upholding industry standards? These questions underscore the importance of collaboration and seeking expertise.

As we’ve explored, partnering with seasoned experts like Kemal Manufacturing can be transformative. So, as you chart your injection molding journey, ask yourself: are you equipped with the proper knowledge and partners to turn challenges into opportunities?

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