3D printing raises the manufacturing capacity

How does 3D printing enhance the manufacturing capacity of high-quality and high-value-added molds?

From the 3D printing projects undertaken by CONOVAWELL over the past year, it’s evident that there has been a significant increase in cases involving the application of 3C electronics. Among these cases, one standout example is a wireless earbuds charging case, which proves to be more complex than it appears.

AirPods on the market

Earbuds may seem simple, but they are quite costly. They have gained a significant market share due to their convenience, efficiency, and high value. The well-known AirPods, for example, can fetch hundreds of dollars despite being similar to other brands’ Bluetooth earbuds.

Consisting of earbuds and a charging box, the latter is typically around 4-5cm in height and only 2cm wide. To ensure proper charging, the charging box must maintain precise dimensions for optimal contact with the power supply.

Despite their delicate appearance, these products adhere to strict manufacturing standards. Therefore, controlling the forming process, particularly in the top cap area, can be challenging.

In the figure above: pic of the internal structure of the charging box’s top cap

Several difficult points

  1. The core inserts feature numerous reverse buckles, necessitating the use of a lifter for molding.
  2. Ordinary machine waterways are unable to process the core inserts.
  3. High core insert temperatures result in long forming cycles, leading to product margin deformation and instability.

In general, manufacturing such products presents two main challenges: poor cooling effects due to structural limitations, making ordinary machining impractical; and uneven mold temperatures causing margin deformation. Both issues can be addressed using 3D printing technology.

3D printing conformal waterways design issue

Regarding the structure, the core inserts feature numerous reverse buckles, necessitating the use of lifters during the forming process. Consequently, conventional machining methods cannot accommodate waterways in the core inserts.

Without designed waterways, molds lacking such features significantly prolong ejection times. This elongates forming cycles and reduces production efficiency, directly impacting product quality.

Additive manufacturing, functioning layer by layer, enables the even distribution of waterways according to product shape. This capability, as depicted in the image below, shortens production cycles and enhances product efficiency.

Pic 3 illustrates the 3D printing of conformal waterways on the top of the earbuds charging box. Hence, transitioning from traditional printing methods to 3D printing mold manufacturing is essential. Once the parameters for injection time, cooling liquid, mold temperature, and other machining parameters are set, mold flow analysis can be conducted. Referring to the data displayed in Pic 4:

In Pic 4, there’s a diagram comparing the mold flow analysis results, specifically the time taken to reach the ejection temperature. With the utilization of conformal waterways technology, the time to reach the ejection temperature is approximately 95 seconds, whereas for ordinary waterways cooling, it’s about 13 seconds. This indicates a 30% increase in cooling efficiency. By addressing the challenges in 3D printing conformal waterways design, the cooling time can be reduced, leading to improved production rates.

Mold temperature control of 3D printing

Mold temperature primarily refers to the temperature of the cavity surface during the forming cycle. Once the mold design and forming process are finalized, it’s crucial to maintain the appropriate temperature and ensure uniform distribution throughout the mold.

Uneven mold temperature distribution can result in unequal contraction and internal stress, leading to deformation or warping in the forming area, thereby impacting the quality and forming cycle to some extent.

The distribution of waterways is one of the factors that affect mold temperature. In traditional molding, issues such as the internal structure of the top cap of the charging box and forming angles can prevent some components from being processed by waterways, thereby affecting mold temperature. Refer to Pic5 for illustration.

Pic 5: Diagram illustrating mold flow analysis of mold temperature

After implementing conformal waterways, the mold temperature is approximately 54 degrees, whereas the temperature for the conventional mold reaches as high as 84 degrees, indicating a decrease of around 35%. Therefore, by comparing the data, 3D printing can effectively regulate mold temperature to achieve a balanced distribution and reduce defect rates.

Pic 6: diagram of polishing performance

The raw material issue of 3D printing mold

Another factor influencing the quality of 3D printing molds is the choice of raw materials. Drawing from years of practical experience in the 3D printing field, CONOVAWELL has developed several proprietary raw materials such as EM181, EM191, and EM201, tailored specifically for 3D printing applications.

For the mold part used in the top cap of the charging box, the material selected is EM191. Apart from ensuring mold rigidity and strength, EM191 also offers rust and corrosion resistance, along with excellent polishing performance.

In summary, based on the mold flow analysis data obtained through modified 3D printing technology, production rates have increased by nearly 30%, while mold temperature has decreased by 35%. Whether it’s enhancing production efficiency, ensuring quality, precise post-processing, or selecting appropriate raw materials, CONOVAWELL is fully equipped to overcome any challenges.

Despite lingering skepticism and reluctance among some mold makers regarding 3D printing technology, we firmly believe in staying ahead of the curve when it comes to meeting high standards and adding value to injection molding products. Leveraging 3D printing technology according to specific requirements is essential for achieving these objectives.