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Global Workforce Challenges for the Mold Making and Engineering Industry

Department of Plastics Engineering, University of Massachusetts Lowell, Lowell, MA 01854, USA
Department of Mechanical System Design Engineering, Seoul National University of Science and Technology, Seoul 01811, Republic of Korea
Authors to whom correspondence should be addressed.
Sustainability 2024, 16(1), 346;
Submission received: 25 October 2023 / Revised: 13 December 2023 / Accepted: 28 December 2023 / Published: 29 December 2023


The mold industry faces unprecedented challenges in the current global economic and social landscape, including increasing environmental concerns and the need for sustainable solutions. To address these challenges, the plastics tooling industry needs to face critical issues associated with the shortage of skilled labor and disruptions to global supply chains. This work reviews and analyzes the global workforce challenges and their relationship to sustainable economic and environmental growth. The characteristics and challenges of the mold-making and engineering industries are assessed and critically discussed. New technologies, such as data-driven automation in design and manufacturing, are discussed, considering their current and future impact on employment in the industry. Ultimately, the paper argues that the mold industry must address these workforce challenges to promote sustainable and continued growth. Indeed, workforce and technology development are the key drivers for the sustainable growth of the mold-making industry, as they support the timely and cost-effective manufacturing of numerous essential plastic products. The industry stakeholders should work on structural solutions to foster a more conducive environment to produce plastic molds.

1. Introduction

Advanced industries are currently facing a significant challenge in the form of a shortage of skilled workers, and the manufacturing sector has particularly been affected by this. The manufacturing industry heavily relies on workers with specific skills and training; however, many countries are experiencing a scarcity of qualified individuals. The shortage can be attributed to several factors, including the decline of vocational education and training programs, an aging workforce, and increasing demands within the industry [1,2,3]. The lack of skilled workers poses numerous obstacles for advanced industries, including production delays, quality issues, and higher costs. In some cases, businesses are even compelled to relocate to countries with a more abundant supply of skilled workers. Alongside the workforce shortage, technological developments add complexity to the manufacturing environment, creating significant challenges for the near and long-term future.
Several measures can be taken to tackle the issue of an inadequately skilled workforce in labor-intensive sectors [4]. First and foremost, investing in education and training is crucial. By allocating resources towards enhancing vocational programs and providing specialized training opportunities, advanced industries can develop a competent workforce capable of competing in the global economy. Additionally, importing skilled workers and considering offshoring options can help bridge the skill gap and meet the industry’s demands [5]. Furthermore, labor-intensive sectors face additional challenges besides the shortage of skilled workers. These challenges include relatively low wages, harsh working conditions, and a lack of job security. These factors make it difficult to attract and retain workers within these sectors [6].
Amidst the pervasive shortage of skilled labor afflicting the entire manufacturing sector, this investigation will focus on the labor-related difficulties specifically faced by the plastics tooling industry. Plastics play vital roles in the production of various mass-manufactured goods, with many of them undergoing extrusion or molding processes. Extruded products encompass a wide range of applications, including pipes, window frames, plates, and films. However, molding is paramount for enclosures, packages, and functional components utilized in automobiles, semiconductors, displays, mobile devices, consumer electronics, and food packages. Injection, transfer, and blow molding processes dominate the fabrication of these components, while compression and rotational molding techniques retain significant relevance. The inherent complexity of these parts necessitates the utilization of diverse molds with varying geometric configurations, scales, complexities, precisions, and durability requirements. The primary challenge lies in concurrently designing, engineering, and manufacturing these molds alongside the associated products, which are poised for imminent market entry [7]. Currently, the expectations placed on new molds for molded parts encompass a wide array of requirements, including aesthetic appeal, dimensional accuracy, and desired properties. These molds must be delivered within specified timelines and at a competitive price point. Consequently, plastic mold making entails a rigorous pursuit of high-quality standards while operating within tight profit margins.
Let us give an overview of the plastics industry. The plastics industry is global and ever-evolving. It has grown exponentially in recent years due to the increasing demand for plastics in various sectors such as automotive, packaging, construction, and many more. In 2019, the global market size of plastics was estimated to be USD 622 billion. This size is expected to reach USD 758.6 billion by 2025 [8]. In 2020, global plastic production was approximately 340 million tons. China, Europe, and the United States are the top three plastic-producing countries, accounting for 65 percent of the global share. The global plastics industry is benefiting from technological advances and reduced production costs, which have led to greater innovation and higher use of plastic in various applications. However, looking ahead, multiple trends in sustainability and environmental initiatives will shape the future of the global plastics industry. Single-use plastics are becoming more heavily regulated, and more sustainable alternatives are becoming popular. Companies are looking for ways to increase circularity while maintaining global competitiveness [9].
Innovations in the plastic industry have led to products with higher performance, durability, and safety while reducing material costs and energy inputs [10,11,12,13,14,15,16]. The use of automation has been growing, and it is expected to accelerate as the challenges facing the workforce continue to become more prevalent. However, this creates a paradigm for the industry, as higher technology will require a highly skilled workforce capable of designing and implementing automated manufacturing.
Concerns about the environmental impact of the plastics industry are continuously growing, and businesses face critical sustainability challenges. Companies are focused on reducing plastic waste, using secondary feedstock, and, in general, finding ways to reduce the impact of plastic on the environment [17]. In the near future, these challenges are going to impact the industry even more as new government regulations are expected to define stricter rules on the use of virgin materials and introduce EPR (Extended Producer Responsibility) laws [18]. As a result, some studies have developed recycling technologies for complex materials. For example, a recent study proposed a method that can separate targeted polymers into multilayer thermoplastic films [19]. Another study investigated recycling thermoplastic-reinforced composites [20].
The sustainable production of plastic parts relies heavily on a continuous supply of molds [21,22]. Once a suitable mold is created, it enables the production of parts in any desired quantity. It is crucial to highlight that the plastics industry heavily relies on a dependable supply of high-quality molds. Over the years, the global mold industry has experienced significant development through cooperative and competitive efforts, leveraging the comparative advantages of different regions.
For instance, in 2020, Korea exported plastic molds worth approximately USD 1.5 billion while importing molds valued at 98 million USD. Most Korean plastic mold exports are destined for the United States, Japan, Mexico, China, and India, while most mold imports are sourced exclusively from China [23]. Korea can cater to the global demand for molds of various qualities, ranging from average to premium. Some molds are provided to offshore Korean manufacturers, while others are solely exported. It is worth noting that the importation of Chinese molds serves the purpose of reducing mold costs, which Korean mold makers cannot meet. The number of low-end mold makers in Korea is consistently declining due to the retirement of small shop owners. These days, global collaboration and cooperation in manufacturing are undergoing significant transformations, and the mold industry must also confront this change.
The mold market worldwide, including all types of molds, is worth more than USD 23 billion. It is expected to grow at a rate of 11.2% every year and reach over USD 68 billion in the next ten years. However, some obstacles need to be overcome for this growth to happen. First, mold makers need to reduce the negative impact on the environment when producing molds [21]. Using sustainable practices that reduce waste and save energy is important, so the mold industry has a smaller ecological footprint [24]. Second, mold makers should focus on continuously improving their processes [11]. This will help them make more profit, improve the quality of their molds, and deliver them faster. By constantly improving their productivity, efficiency, and cost, they ensure molds are provided on time without compromising quality. Third, keeping skilled workers in the mold-making industry is crucial. These workers are essential in avoiding mistakes, preventing waste of energy and materials, and developing new and better ways of doing things. This challenge is closely related to the first two because it is harder to reduce waste and improve processes without skilled workers. In conclusion, the global mold market has a lot of growth potential, but there are important challenges to be faced. By reducing the environmental impact, continuously improving processes, and keeping skilled workers, the industry can overcome these challenges and succeed.
Automation in the mold-making industry, a key aspect of Industry 4.0, presents both opportunities and challenges for the workforce [25]. While advanced technologies enhance efficiency and precision, they also demand a skilled workforce capable of managing complex automated systems. This shift necessitates upskilling and retraining programs to bridge the gap between traditional craftsmanship and modern technological demands [26]. Striking a balance is crucial to harnessing the benefits of automation without sidelining the human touch. The mold-making industry faces the dual challenge of embracing innovation for competitiveness while ensuring a resilient workforce capable of adapting to evolving technological landscapes.
Given the ubiquity of plastic parts in countless products, the timely delivery of high-quality plastic molds at an affordable price is crucial for sustainable development. However, a skilled workforce is crucial to achieving this objective, and current challenges in training and uncompetitive wages are hindering its development. This paper posits that a transformation in both job and industry characteristics is essential to address these constraints. To foster a more favorable environment for plastic mold production, stakeholders are strongly urged to implement the recommendations outlined in this paper, thereby enabling the industry to flourish and meet the ever-growing demand for high-quality, affordable plastic molds.
This study reviews the current status of the mold-making and engineering industries by analyzing their characteristics, challenges, and outlook. This work aims at identifying the workforce challenges and their impact on environmental and economic sustainability. In our analysis, we develop a strategy for retaining and engaging a skilled workforce in the plastics tooling industry. Considering the declining trend in the availability of such workers, the focus will be on exploring ways in which mold makers can sustain profitability and productivity. Additionally, this research will examine how mold makers can contribute to the reshoring and nearshoring of manufacturing operations.
In this study, we aim to first examine the characteristics of the tooling industry and explore the challenges it faces. Additionally, we will delve into the content of a panel discussion organized by SPE-MTD to assess the practical needs of industry professionals. Subsequently, using the PESTLE framework, we will propose a technological alternative centered around automation as a methodology to address workforce challenges. Furthermore, we will present political and social alternatives for implementing and achieving these technological solutions.

2. Characteristics of the Tooling Industry

2.1. Molds

The significance of molds in manufacturing is paramount when it comes to meeting the demands for large volumes of specific design shapes across diverse industries, including automotive, consumer electronics, electric equipment, packaging, toys, household goods, and precision optics. The increasing emphasis on design in the market has rendered the precision and quality of molds essential in producing these goods.
Molds serve as critical instruments for the efficient mass production of custom-designed shapes utilizing various materials, such as metals, plastics, glass, and rubber. To ensure longevity and endure the rigors of mass production, their construction typically involves using special alloys and hardened steel. The selection of materials considers factors such as anticipated usage cycles, material properties, and design complexity, striking a balance between cost and durability. Given their popularity and diverse applications, various manufacturing methods rely on molds. However, it should be noted that some polymer processing methods, such as FFF (fused filament fabrication) [27,28,29,30,31] and tow placement, are fulfilled without molds [32]. Injection molding is the most extensively employed technique for manufacturing consumer electronics such as televisions, cell phones, and computers. Molds can encounter different temperature and pressure conditions, including low-viscosity thermosetting resins, high-viscosity thermoplastic melts, and molten aluminum. Specifically, unless explicitly stated otherwise, the term “mold” refers to the type utilized in mass production through injection molding with thermoplastic resins [7].
In addition to conventional injection molds, there are also special molds that are used for different processes. Micro-injection molding requires mold inserts with micro-patterns and is used to produce small, complex parts with high accuracy [33,34,35,36,37]. Thermoset processing uses molds that are heated to cure the plastic and are used for parts that need to be strong and heat-resistant. Blow molding is used to produce hollow plastic parts, such as bottles, by heating the mold and then blowing a molten plastic tube into it. Transfer molding is used to encapsulate semiconductors by heating the mold and then injecting molten plastic into it, which surrounds the semiconductor and then cools and hardens. Compression molding is used to produce rubber parts by heating the mold and then placing a sheet of rubber in it, which is then compressed and cured. RTM (resin transfer molding) is used to produce composite parts by filling a mold with resin with an embedded fiber structure, which then cures and the part is removed from the mold [38,39]. These special molds are used for the mass production of a variety of products. Conversely, metal products are typically shaped through plastic deformation, encompassing cutting and shaping processes. Drawing, roll forming, and extrusion produce steel pipes and beams. Forming methods manufacture curved surfaces composed of steel and other sheet metals. The tools used for these processes are called dies. Generally, dies utilize high-strength materials to shape metal components, whereas molds encompass a broader spectrum of materials. Usually, tooling encompasses both dies and molds, and it is common to see a single company manufacturing both. Since the manufacturing of dies and molds shares similar characteristics, they can be addressed together. However, this study focuses on injection molds to delve deeply into a specific topic. Many aspects of the findings from this research can also apply to the die manufacturing industry.

2.2. Characteristics of Mold Making

Mold making is a specialized form of machining that creates tools for the mass production of custom-designed shapes [40]. The main objective is to produce durable tools for consistently manufacturing identical products. Manufacturing constitutes a significant portion of the life cycle cost of molds [21]. Mold manufacturing alone contributes to 30% of the overall cost, while the materials used for molds represent 10–30% and are often recyclable. Evaluating the environmental impact of mold-making from a manufacturing perspective is crucial.
Precision machining processes, such as CNC milling, grinding, turning, and EDM, are integral to mold production [41]. The mold-making industry heavily relies on EDM, with over 80% of EDM tools dedicated to mold production. Analyzing machining processes is vital for assessing the environmental impact of mold manufacturing, with a particular focus on energy consumption by machine tools, notably CNC milling and EDM. According to a mold-making time study, CNC milling and EDM account for over 80% of the machining time [42]. In contrast, other machining processes like CNC milling, grinding, turning, and EDM serve a broader range of applications. These processes involve shaping, cutting, or removing material to achieve specific shapes, sizes, or surface finishes. The focus is typically on directly creating finished products or components rather than producing tools for mass production.
Mold making necessitates intricate and precise machining operations to replicate desired shapes accurately. High precision is crucial in producing molds that consistently and accurately reproduce the desired shape during large-scale production. In contrast, other machining processes may vary in complexity and precision requirements depending on the specific application, with an emphasis on achieving desired dimensions and surface finishes rather than replicating complex shapes for mass production. As a result, mold making frequently necessitates manual or advanced finishing, comprising a significant portion of the overall operation time, approximately 17% [43,44].
Injection molds have a limited number of cycles depending on the material used, and the Society of Plastics Industry (SPI) classifies them into five classes based on this criterion. Class 101, capable of handling the highest number of cycles, can exceed 1 million shots, while Class 105, the least durable, cannot surpass 500 cycles. Molds made of aluminum typically perform around 10,000 cycles, falling into Class 104 (up to 100,000 cycles). Traditionally, quick delivery molds (QDM) have utilized aluminum, but recently, rapid tooling based on additive manufacturing is becoming more prevalent. With ongoing improvements in material properties, it is anticipated that in the long term, these advancements can be applied to high-class mass production molds. This study will further explore this aspect in 5.5. as a significant alternative [45,46].

2.3. Environmental Considerations

The production of molds involves several elements that contribute to their environmental impact. Materials used for molds, as well as fixtures and cutting tools, are often metal and recycled; however, coolant usage remains inefficient, emphasizing the need for effective coolant utilization or dry machining. Energy consumption by utilities like HVAC and lighting during production is a significant factor, with researchers focusing on green buildings and building information systems.
According to Kong, the machining-intensive nature of mold manufacturing makes energy consumption a major environmental impact [42]. CNC milling and EDM are the most time-consuming operations in mold manufacturing, and their energy consumption characteristics are important for estimating the environmental impact of this industry. Some special mold materials use cobalt and some rare elements, but the amount and impact can be considered small. If the process fails, materials and energy are wasted, so by achieving the original purpose of the process, environmental factors can be minimized.
Life cycle assessment (LCA) is a method for evaluating the environmental impact of a product throughout its lifecycle, considering manufacturing, use, and disposal. A mold maker can use the LCA tool to assess different materials and processes for a product. This helps the mold maker choose materials and processes with the lowest environmental burden. From the perspective of LCA, the lifespan of molds is a critical issue. To enhance it, it is crucial from a technical standpoint to systematize mold maintenance, including preventive maintenance, and to perform necessary repairs appropriately. Molds undergo fatigue damage due to repeated mechanical-thermal cycles and impacts. The repair of molds is a technically significant field, necessitating the prediction of failures and the selection of appropriate repair options such as welding and material deposition based on the specific circumstances [47].

2.4. Mold Making and Engineering Workforce

Mold manufacturing demands a high level of specialized skill and expertise, making it challenging to replicate through automation. We will address automation concerns later. The programming and operation of automation equipment necessitates skilled labor, and finding such skilled workers can be problematic in certain areas. Overall, mold manufacturing is a highly specialized and complex process that requires a combination of advanced technology and skilled labor. General mold technology is described in a comprehensive way in several excellent works of literature [7,48].
However, in practice, the task of manufacturing a mold is unlikely to be performed only with such written and illustrated knowledge and requires the acquisition of empirical knowledge that is usually handed down [49,50]. This complicates the restoration of industrial ecosystems after their collapse. Therefore, the core of the public efforts to train manpower in the mold industry was to try to maintain this apprenticeship system continuously. The mold industry requires a workforce with strong communication skills, up-to-date engineering skills, and patience for the intensive training process, but the workforce problems start when the industry in general is not profitable enough to provide appropriate compensation. Let us discuss this challenge further and suggest possible solutions.
The engineering workforce in the mold-making industry consists of college-educated professionals with backgrounds in plastics engineering, mechanical engineering, mold design, or related fields. These individuals blend traditional craftsmanship with modern technological expertise, utilizing advanced tools such as simulation and optimization software for efficient design processes. Knowledge-based engineering and design automation play crucial roles in accelerating and standardizing mold development. Collaborative interdisciplinary teamwork and continuous learning are integral aspects of their roles, ensuring adaptability in the dynamic landscape of the plastics industry.
The mold engineers must undergo training for systems that require extensive education, such as CAD, simulation, measurement-related tools, and long-term learning for equipment like machining centers and injection molding machines. The complexity of the tools used in real-world applications makes it challenging to achieve sufficient proficiency through education at universities or colleges alone. Additionally, when these tools and systems are associated with automation, programming or scripting may be necessary, further raising the demands of the required training.
Despite their proficiency, these engineers face challenges in keeping pace with rapid technological advancements, necessitating ongoing skill development. Economic pressures and environmental concerns present additional hurdles for sustainability in the plastics tooling sector. Future trends involve a shift toward eco-friendly materials and processes, emphasizing circular economy principles and energy-efficient technologies. Engineers must navigate these challenges adeptly, balancing innovation, economic considerations, and environmental consciousness.

2.5. Impact of Manual Labor

Labor-related factors primarily affect social aspects, particularly health, rather than the environment. In addressing today’s environmental issues, the term “environment” refers to an environment suitable for human and earthly organisms to thrive. Therefore, the impact of labor on human health and social perspectives is an immediate and significant concern.
Although automation has been considerably implemented, human labor still constitutes a significant portion of tooling. Manual processes play a crucial role in tasks that are challenging to automate or demand meticulous control over the final product. These include manual finishing, manual tooling, assembly, fitting, inspection, quality control, and functional validation.
Manual finishing is often necessary after initial machining operations to achieve the desired surface finish, remove imperfections, or enhance mold details. Manual finish techniques include deburring, polishing, texturing, and marking. Polishing involves gradually refining the surface using abrasive materials, while surface texturing creates intended textures through engraving, etching, or manual carving. Skilled technicians execute these techniques to achieve accurate replication. However, manual finishing is labor-intensive and time-consuming compared with automated alternatives, and it involves working with harmful materials near human workers. For this reason, polishing accounts for approximately 10% of the total mold cost. According to the SPI guideline, polishing is performed using different processes according to the standard. Considering the characteristics of the various shapes of the mold, various methods, such as mechanical, chemical, electrolytic, ultrasonic, hydrodynamic, and magnetic, must be used. Each of these methods requires experienced people, creating difficulties in securing technicians for each type of technology. Consequently, reducing reliance on manual finishing and exploring automation options can streamline the mold-making process, increase efficiency, and improve overall outcomes [51].
Manual assembly ensures proper alignment and functionality by fitting mold components together, inserting inserts or cores, and securing them with screws, bolts, or clamps. Manual inspection processes play a critical role in maintaining mold accuracy and quality. Mold makers carefully examine the mold for defects, imperfections, or dimensional deviations using measuring tools such as calipers, gauges, or coordinate measuring machines (CMMs). It is worth noting that automating the CMM has been a significant objective for an extended period of time. Nonetheless, achieving automation has proven to be challenging [52]. Additionally, manual processes are involved in conducting test moldings to verify functionality and performance, including injecting the mold with the desired material and evaluating the resulting parts for any issues.
Achieving complete automation in mold fabrication currently appears to be nearly impossible. However, minimizing the impact of labor seems effective by automating processes as much as possible [53], particularly by reducing manual finishing [51,54] and metrology [55]. Metrology is essential due to the high-dimensional precision requirements in mold making. It involves a combination of human labor and automated processes. In particular, visually inspecting molds for surface defects or performing manual measurements with handheld tools may continue to require human involvement. Skilled technicians conduct manual inspection and measurement tasks, carefully assessing dimensional characteristics and surface quality. Automation, including coordinate measuring machines (CMMs), optical measurement systems, and laser scanners, has significantly improved the speed, accuracy, and efficiency of measuring molds’ dimensional features. Specialized software analyzes and processes measurement data obtained from automated systems, providing detailed reports and statistical analysis. Overall, metrology in mold making involves a balance between human labor and automation. The specific balance depends on the measurement complexity and available technology.
In addition, the mold validation process also requires skilled human labor. In the case of injection molding or press forming, simulation is applied during the design phase, which is then validated through actual tryouts. Modifying the mold and die based on these results also demands experienced personnel. These individuals must have a comprehensive understanding of mold and the molding process, which requires high education and experience. In some cases, dissatisfaction with the molding results can be addressed by adjusting the molding conditions, so the decision on how extensively the mold should be modified relies on human judgment.

3. Challenges in the Tooling Industry

3.1. Tooling Industry Challenges

Various business challenges in the tooling industry will be examined here, with a focus on workforce, supply chain, security, and technological aspects.
Above all, implementing new technologies in the tooling industry can be challenging due to the skills gap between the current workforce and the technology being introduced. As industry advances and new technologies are developed, many existing workers may not have the necessary skills to work with the latest technology. The cost can also be a challenge, as many of the newer technologies are expensive and require high maintenance levels. Lastly, many technological advancements may be too fast-paced or too complex for the current workforce, leading to difficulty adapting to the new systems.
Injection mold making is an important industry that plays a key role in producing a wide range of plastic products. This industry involves making molds or tools used to mold molten plastic into specific shapes, sizes, and shapes. Injection molding is a widely used manufacturing process in which molten plastic is injected into a mold to create a variety of products, including toys, automotive parts, medical devices, and household items.
Most industrial design results are mass-produced through injection molds. These designs often need to be secured within a manufacturer’s merchandising strategy. In other words, mold makers can predict what products their customers are planning and can accidentally or intentionally leak these designs against their customers’ interests. Therefore, security becomes a crucial issue in the tooling industry, and from this perspective, it is essential to instill trust in customers.
The injection mold manufacturing industry is highly specialized and requires a skilled workforce with expertise in injection molding processes, metrology, mold design, material engineering, and machining. This process involves designing and creating molds using computer-aided design (CAD) and computer-aided manufacturing (CAM) techniques [56]. In addition, selecting a mold material that meets the requirements and setting specific machining conditions require an engineering process. Furthermore, it is challenging to estimate the manufacturing cost of a mold with acceptable accuracy and present an appropriate price to the customer, thus requiring significant experience in such estimation. In addition, deep knowledge and sufficient know-how are required for sales technicians to fully understand the customer’s needs through communication with them and reflect them on the mold.
To stay ahead in this field, businesses must constantly innovate and enhance their procedures. There is a considerable need for high-quality molds that are long-lasting and can survive frequent use. As a result, the business is highly regulated, with producers required to meet severe quality control standards. Global trade dynamics have a significant impact on the injection mold manufacturing sector as well, since many manufacturers outsource their production to nations with lower labor prices. The geography of the sector has significantly changed as a result, with Asia, North America, and Europe being the key players.
In general, the manufacture of a wide variety of products relies heavily on the injection mold manufacturing business, which is a significant component of the global manufacturing supply chain. However, since the mold industry is crucial to each country’s core industrial interests or even affects the defense industry, it cannot be left to international trade based on comparative advantage. This is why industrialized countries strive to support the mold industry. Nevertheless, many companies in the EU continue to maintain a family business structure, where the tradition and experience of the company become crucial marketing points. In Korea, Japan, and the EU, it can be observed that these companies depend on research institutions supported by the government for technological advancements. Alongside these industrial characteristics, a reliance on apprenticeships for workforce training has the potential to make prospective talents perceive this industry as outdated, exacerbating the workforce challenges mentioned earlier. The next section aims to examine this further.

3.2. Workforce Challenges

Recruiting and retaining workers in the mold industry can be a challenge due to the costly and highly specialized nature of the industry. Many of the industry’s advanced manufacturing processes require personnel with specific technical expertise, making it difficult to find the right employees. Additionally, due to the complexity of the industry, recruiting and training new employees can often be costly and time-consuming. Retention can be a challenge as well, as many of the workers in the industry are not aware of the long-term opportunities for career progression that the industry provides or are not invested in the industry’s mission. With advances in technology, the industry is constantly evolving, requiring workers to find new, creative ways to stay ahead of the curve [57].
In the coming years, the mold industry will face a significant skill gap due to rapid advancements in technology, changing customer demands, and the need for greater environmental sustainability. Many of the current skills needed to work in the mold industry are outdated and do not meet the demands of the changing industry. In order to bridge this gap, the industry needs to invest in training and education initiatives that will prepare workers for the new technologies and advances in the industry. This could include investing in specialized training and certifications that are tailored to the specific needs of the mold industry. Additionally, the industry should consider creating apprenticeship programs to teach younger generations the skills and knowledge needed to be competitive. As of now, it seems difficult to completely move away from apprenticeship-based training in the mold industry. In the future, the mold industry will need to stay ahead of the curve and be prepared to implement new technologies and processes as the industry evolves. This will require developing innovative strategies and solutions that are tailored to the unique needs of the mold industry.
The mold industry faces an urgent need to increase diversity and inclusivity. This would help to create a more equitable and diverse workforce, leading to greater creativity and innovation, as well as better decision-making and improved customer service. Additionally, it would help to attract and retain top talent, improve morale and engagement, and promote a greater understanding of the needs and perspectives of a wide range of customers. Finally, such efforts could help create a more welcoming and accessible working environment for historically underrepresented and marginalized groups. Companies should focus on cultivating a culture of respect and inclusion, provide meaningful opportunities for development, and use metrics to track progress in achieving diversity and inclusivity goals.
Furthermore, another significant issue is the predominant presence of skilled technicians over research and engineering positions in mold-making. As of 2022 in South Korea, the number of skilled technicians in the mold-making sector is 52,897, whereas research and engineering positions are only 4001 and 4404, respectively [58]. This indicates that the industry is addressing the demands of highly technical products through a labor-intensive approach. It is anticipated that resolving workforce issues will be challenging if this distribution of labor persists.
Overall, the mold workforce is facing a unique set of challenges related to generational change. Increasingly, aging baby boomers are retiring from the mold industry, leaving a large gap in qualified and experienced workers. This is being compounded by a lack of interest from younger generations in seeking mold-related jobs, leading to a potential talent crisis. Consequently, there is a need for companies in the mold industry to create a workforce that is diverse in both experience and age. This can be accomplished by providing incentives to attract new talent, such as competitive salaries and benefits, as well as fostering a work environment that appeals to younger workers. On the education front, there needs to be greater promotion of the mold industry to attract younger generations, including offering more career exploration opportunities and internship programs. With the right strategies in place, the industry could be well positioned to leverage the power of generational change in the years to come.

3.3. Educational Challenges

The mold-making and engineering industry faces critical challenges related to education and training, hindering the development of a skilled workforce. In this section, we will address the specific issues affecting vocational high schools, universities, and on-the-job training programs in meeting the demands of the industry [59].
We should first clarify that in most countries, mold makers are typically trained on the job at a young age and develop strong expertise with practice. Continuous growth has been giving mold makers opportunities to grow into managerial roles. However, a lack of formal and continued training has led to an experienced but old and uniform workforce. Moreover, when training only happens through direct work experience, many obstacles can be faced due to business demands for timeliness, efficiency, and cost reduction. The mold engineering workforce has also been lagging due to the sparse offering of university-level mold design and manufacturing courses. Most commonly, engineers in the industry have a mechanical engineering background and enter the field with minimal knowledge of injection molds. Hence, they need training on the job and cannot be productive from the beginning of their careers. This is further validated by the many opportunities available to students who graduate from the few programs that offer education in mold design, engineering, and manufacturing.
Technical high schools, while serving as a potential source of skilled labor for the mold-making industry, face significant challenges in keeping pace with rapid advancements in manufacturing technology and processes. Due to limited resources and funding constraints, these institutions often struggle to integrate cutting-edge machinery and software into their curricula. Consequently, graduates may lack the practical skills demanded in the modern workplace, resulting in a significant disconnect between the skills they possess and the industry’s actual requirements [60]. This disparity leaves employers with a workforce that requires additional training and adjustments to be productive, creating inefficiencies and hampering overall growth in the mold-making sector. Moreover, a shortage of experienced mold-making professionals willing to transition into high school teaching roles poses a significant educational obstacle. Instructors with practical experience and a comprehensive understanding of the industry are essential for providing relevant training. The lack of such instructors can compromise the quality of education and leave students ill-prepared for real-world challenges.
For engineering graduates, insufficient collaboration between educational institutions and industry can lead to a skills mismatch. A lack of industry input means curricula may not align with current industry trends and demands. Indeed, the existing education system sometimes fails to address the specific skills required in the mold manufacturing industry. Graduates may possess theoretical knowledge but lack hands-on experience. While engineers do not typically work directly as mold makers, proficiency in mold-making techniques enables their ability to competitively produce efficient designs while understanding manufacturing constraints. Most often, designs proposed by engineers could be returned by mold makers due to features that make them impossible or too costly for machining. However, the necessary skills are learned through direct experience, not in a traditional classroom setting. This mismatch between skills and job requirements has been hampering the efficiency of engineering graduates. Hence the importance of educational programs that demonstrate manufacturing processes in relevant laboratory environments [61] and expose students to experiential learning activities. For example, Masato and Johnston assessed the effectiveness of teaching a mold engineering class through simulation and laboratory activities [62]. Kazmer et al. explored the use of the case study methodology to teach plastic product design, allowing students to learn through direct experience with design, data analysis, and critical thinking [63].
On-the-job training is indispensable in the dynamic mold-making industry. Unfortunately, some companies neglect to allocate sufficient resources for continuous employee training. This absence of professional development opportunities can result in stagnation, hindering the workforce’s adaptability to emerging technologies and best practices. Inadequately trained employees may struggle to optimize productivity and product quality, leading to potential setbacks for the company and the industry. Recognizing the value of ongoing training and investing in upskilling initiatives is crucial for empowering the workforce to stay updated with industry advancements, enhance their expertise, and drive innovation in the mold-making sector.
Overall, addressing the education-related challenges in the mold-making industry is crucial for developing a competent and skilled workforce [64]. Upgrading curricula to incorporate the latest technology, attracting qualified instructors, fostering stronger ties with industry, and emphasizing continuous training are essential steps to ensure that the workforce remains competitive and capable of meeting the industry’s demands. By collaboratively tackling these challenges, the mold-making sector can thrive in an ever-evolving global market.

3.4. Supply Chain

Recent trends in maintaining domestic supply chains are driven by several factors. Above all, the COVID-19 pandemic revealed vulnerabilities in global supply chains, prompting a focus on resilience and risk mitigation [65]. By reducing dependence on foreign sources, countries aim to ensure a more robust response to disruptions. Additionally, supporting domestic industries stimulates economic growth and job creation, contributing to overall prosperity. By exerting control over standards and regulations, countries can ensure compliance with domestic requirements and have greater oversight. Environmental considerations also play a role, as shorter supply chains reduce carbon emissions associated with long-distance transportation. Maintaining domestic supply chains also supports local businesses, fostering innovation, collaboration, and competitiveness in the domestic market. National security is another key consideration, as governments recognize the strategic importance of having essential industries within their borders. Domestic supply chains provide reliable access to critical goods and services, particularly in sectors like defense and healthcare. These factors collectively drive the recent emphasis on maintaining domestic supply chains for enhanced resilience, national security, economic growth, control over standards, and support for local industries.
The mold industry plays an important role in defense and wartime scenarios by manufacturing various military components such as weapons, ammunition, and vehicles. During the conflict period, the demand for molds increased significantly. The industry has specific requirements to meet the needs of defense applications, including producing high-quality molds that can withstand military use and produce precision components. Short lead times are essential, and mold manufacturers must deliver molds quickly to meet urgent military requirements. A secure supply chain is essential to ensure uninterrupted access to needed materials and equipment. Innovation is also important, as the industry must develop new technologies and processes to produce more efficient, effective, and affordable molds. Examples of molds used in defense applications include weapon molds for firearms, ammunition molds for bullets and shells, and vehicle molds for tanks, airplanes, and ships. The mold industry plays an important role in providing the armed forces with essential components to protect the country by meeting the requirements of national defense and wartime.
The economic and non-economic factors mentioned above are deemed sufficient reasons to justify the need for maintaining the mold industry within the country at the national level. This work will no longer provide detailed explanations regarding the necessity of it.

3.5. Mold Maker Demographics in the US

The demographics of mold makers in the United States show that the industry is typically made up of experienced professionals who have been working in the field for many years. There is a notable presence of mold makers in their 40s or older, which indicates a workforce with significant expertise and knowledge. However, there is a growing need for younger individuals to enter the industry to ensure its sustainability and fill the potential skills gap.
Historically, mold making has been a male-dominated field, but efforts are being made to promote diversity and inclusion, encouraging more women to pursue careers in mold making. The education and training pathways for mold makers vary, but many acquire their skills through on-the-job training or apprenticeship programs. Formal education in related fields such as machining, tool making, or industrial technology can also provide a solid foundation for a career in mold making. Certain regions in the United States, such as Michigan, Ohio, California, Illinois, and Pennsylvania, are known for housing clusters of mold-making companies. However, mold-making facilities can be found in many other states as well, catering to regional manufacturing needs.
The Employment Projections program at the U.S. Bureau of Labor Statistics shows that the mold-making workforce in the US is aging, with the majority of workers over the age of 45 as presented in Table 1 [66]. A shortage of skilled workers entering the industry to replace retiring workers is also reported. Tool makers earn a median annual wage of USD 57,000, while mechanical engineers with bachelor’s degrees earn a median annual wage of USD 95,300. This means that US mechanical engineers typically earn about 70% more than tool and die makers. In South Korea, a comparable pattern can be observed, although the wage gap is narrower. The median monthly wage for mold engineers is USD 2875, whereas for mechanical engineers, it stands at USD 3777 [67]. This wage gap is considered a major hurdle to attracting and retaining highly skilled professionals in the mold-making industry. The American Mold Builders Association (AMBA), as a relevant representative organization, is committed to prioritizing workforce development solutions as a core aspect of their mission to promote salary growth, among other things that will benefit the industry [68]. Indeed, the difference in wages between these two occupations can be attributed to a number of factors, including the level of education and training required, the skills and experience needed, and the demand for these workers in the labor market. The job outlook for this occupation is stable, with about 44,100 openings projected each year, on average, over the decade. Most of these openings will be due to workers retiring or leaving the workforce for other reasons. The highest-paying states for mold makers are California, New York, and Pennsylvania. The majority of mold makers work in manufacturing industries, such as the automotive and aerospace industries.

3.6. Reshoring

Reshoring entails the process of relocating manufacturing and services back to the United States from abroad [69]. This approach offers a rapid and effective strategy for enhancing the American economy, as it contributes to the equilibrium of trade and budget disparities [70]. Moreover, it curbs unemployment by generating high-quality, well-compensated manufacturing employment opportunities while simultaneously cultivating a proficient labor pool. This movement back to domestic operations also yields advantages for manufacturing enterprises. These include the mitigation of overall product expenses, enhancement of financial statements, and heightened efficacy in introducing product advancements.
Geopolitical factors have led to a number of plastic manufacturing companies moving their production hubs to the United States [71]. This has increased the demand for molds in the country, as OEMs benefit from having their supply chains closer to home [72]. The American Mold Builders Association (AMBA) had previously appealed for the continuation of import tariffs on Chinese molds, but these tariffs were temporarily suspended in response to demands from the plastic industry [73].
American mold makers argue that it is not profitable to manufacture molds by relying on cheap labor in overseas countries. They point out that there are many factors to consider, such as communication problems, impact on the entire manufacturing process, industrial importance, delivery time, and quality [73]. In 2022, the Reshoring Initiative® estimated that five million manufacturing jobs were still offshore, as measured by a USD 1.1 trillion/year goods trade deficit, hence suggesting the potential for significant future growth.
The relocation of plastic manufacturing companies to the United States can potentially give rise to conflicts among stakeholders. In this context, the mold-making industry may not necessarily benefit from the stream of the reshoring trend. This implies that the mold-making industry should reform to benefit from this trend. In other words, it means that there is a need for the ability to maintain low mold production costs itself rather than relying on domestic manufacturing advantages or external factors such as tariffs in order to stay competitive.

4. Global Perspective on the Next Generation of Mold Engineers

The International Committee of the Mold Technologies Division (MTD) of the Society of Plastics Engineers (SPE, Detroit, Michigan) organized a panel discussion in April 2021 to address the workforce development challenges faced by the mold making and engineering industry [74]. The SPE MTD is one of the leading professional societies for mold makers, designers, and engineers. The division supports workforce development activities for industry professionals, interns from technical high schools, and college students. This section provides insights from the discussion, highlighting the global perspective on the next generation of mold builders and engineers. Industry experts from various countries, industries, roles, age groups, and backgrounds shared their strategies and perspectives on recruiting and training in the industry.
The discussion revealed that the industry encounters significant challenges when it comes to recruiting skilled personnel, ranging from technicians to engineers. Some key issues identified include the difficulty in finding suitable candidates, replacing retiring employees, motivating young people to join the manufacturing sector, and the shortage of individuals being educated as toolmakers or pursuing engineering roles. Furthermore, universities tend to prioritize metalworking over courses focused on mold design for injection molding, making it challenging for students to acquire the necessary skills. Engaging students early on in their educational journey has been reported as crucial to addressing this issue effectively.
To overcome the challenges of searching for a skilled workforce, the panel discussion highlighted several successful hiring strategies. These strategies include targeting underrepresented communities, advertising job opportunities, and actively seeking candidates who are willing to relocate. Companies have found valuable resources in military veterans and remote workers from international locations. Embracing a global workforce that addresses the diverse educational needs in manufacturing is also crucial, in agreement with reports from Deloitte [5]. However, this requires efforts to integrate diverse candidates into the company culture and resources to facilitate their onboarding and development. Creating an appealing industry culture and showcasing the “cool” factor of manufacturing has also proven effective in attracting talent. Companies have actively contributed to students’ education by participating in events organized by the Society of Plastics Engineering, which helps foster interest in the industry. New technologies such as simulation or additive manufacturing (AM) can also be leveraged to motivate and engage new hires [75,76].
Additionally, rather than focusing solely on technical skills at the hiring stage, companies have started to prioritize investments in training and development. Companies in the mold-making and engineering industries have implemented various training and educational strategies to develop new hires and foster the growth of current employees. Customized training programs and mentoring initiatives have proven to be effective in maximizing the potential of new hires. Practical experience on the shop floor and program management skills are crucial for individuals working in engineering positions. Companies also play a role in helping new hires create networks within the organization, promoting collaboration and knowledge sharing. Recognizing the diverse backgrounds of new hires, individualized onboarding training programs have been implemented to ensure that individuals with non-technical backgrounds can contribute effectively and align with the company culture.
Overall, the panelists agreed that by addressing these workforce development challenges and implementing effective recruiting, training, and educational strategies, the mold-making and engineering industry can enhance its ability to meet the demands of a rapidly evolving global market.

5. Strategic Plans

5.1. Status and Prospect

It is difficult to find home appliances or consumer products that are not manufactured using molds. From the dollar shop to the Apple Store, the exterior parts and internal structures of the goods are made by the injection molding process. To ensure the sustainability of products throughout their lifecycle, from development to manufacturing and sales, a dependable mold supply chain is essential. In a situation where reshoring is currently being widely promoted by legislation such as the IRA (Inflation Reduction Act), how to make the mold industry competitive in countries where wages are already high has already become a key task. The German Industry 4.0 suggests a layered pyramid model that pursues digital transformation. At the root of the need for such an abstract, three-dimensional concept lies the workforce issue. Of several major cost sources, the workforce has the most fundamental and critical impact on the industry. As aforementioned, the mold-making industry is more heavily influenced by the workforce.
The current status of the mold-making industry can be described as:
  • This is a mature industry in which it is difficult to expect large productivity improvements.
  • Hiring and training are a huge burden for mold makers.
  • Experiential knowledge affects the mold manufacturing process, and the training is also focused on this part.
  • Many small companies compete in the mold market.
  • At the entry level, the mold industry pays less than the average mechanical engineer wage [66,67].
The challenges facing the workforce can be analyzed in the context of labor relations. The PESTLE framework has been chosen for the analysis of similar problems [77,78,79].
Once again, the workforce challenge issue is sought to be analyzed within the framework of the PESTLE framework. The various aspects examined previously in this framework are intended to be reorganized.
Let us first examine it from a political perspective. Due to the freedom of trade supported by policies so far, competition from low-wage countries can exert pressure on domestic wages in the mold-making industry. However, as mentioned earlier, conditions are forming that could significantly trigger reshoring in the United States, driven by policies such as the IRA. Nevertheless, relevant government regulations are likely to persist in advanced economies. Labor regulations related to safety, working conditions, and environmental impact may act as hindering factors for reshoring. If the government’s investment in research and development undergoes changes, there is a possibility of promoting reshoring. Government support for research and development in the mold-making industry can stimulate innovation and generate new job opportunities. If the support for such R&D actively contributes to smart manufacturing, as mentioned earlier, it could lead to successful outcomes and innovations.
Second, let us delve into the economic aspects. This is inherently tied to the profitability of companies in the mold manufacturing sector. As customer-induced cost pressures rise, wages decline, posing challenges to attracting and retaining skilled workers. Addressing this necessitates a scenario where the profit margin of molded products increases, thereby alleviating cost pressures. However, practical obstacles exist in anticipating this scenario. Moreover, alternative sectors may entice talent away from mold manufacturing by offering higher wages and better working conditions. Recognizing and tackling these issues seems formidable for individual mold companies without external adjustments or interventions. When customers demand more intricate molds, the situation may not necessarily translate to higher value-added, which could enhance the profitability of mold manufacturing companies. For example, in scenarios where there is a call for high-precision and complex molds, a workforce with elevated skills becomes imperative. Following the breakdown of the workforce supply base, even if the overall industry and technological standards are high, sourcing personnel capable of manufacturing such molds might prove challenging.
Third, from a social perspective, the mold-making industry faces unfavorable conditions. A negative perception has developed, associating the industry with dirty, hazardous, and low-skilled jobs. This perception discourages young individuals from entering the field, consequently accelerating workforce aging. As mentioned earlier, an aging workforce demographic contributes to a skills gap and labor shortage as seasoned workers retire. Many potential workers may be unaware of the diverse and rewarding career opportunities within the mold-making industry. Additionally, the lack of affordable and easily accessible training programs in education can hinder the workforce’s ability to acquire essential skills for advanced mold-making practices.
Fourth, technological aspects are now supportive of the mold-making industry. As aforementioned, automation technologies are maturing, resulting in the implementation of smart manufacturing in some sectors, and the digital twin deepens it. In the meantime, the rapid pace of technological change requires continuous upskilling and reskilling of the workforce to adapt to new technologies and processes.
Fifth, delving into the intricate legal landscape, which is inextricably intertwined with political considerations, is vital. Stringent safety regulations, while commendable for prioritizing worker well-being, can potentially increase training and compliance costs, impacting the industry’s overall competitiveness. Labor laws governing overtime, minimum wage, and benefits directly affect the cost of employing workers. Furthermore, recent immigration restrictions may limit the availability of foreign talent, further exacerbating the labor gap. While these aspects might exhibit minimal long-term fluctuations within an advanced nation, recognizing them as current realities is crucial for navigating the operational landscape.
Lastly, environmental issues should be emphasized. Sustainability concerns are raised. The growing focus on sustainability may require changes in materials and processes, impacting the workforce and requiring new skills. Environmental regulations can add to the cost of production and make the industry less competitive. The mold-making industry needs to find ways to reduce its environmental impact while still maintaining its competitiveness.
Based on these observations, overcoming the workforce challenge faced by the mold-making industry can be achieved through a strategy centered on increased profitability. This necessitates a focus on cost reduction, especially since raising mold prices is not a viable option. Cost reduction and quality enhancement can be simultaneously realized by leveraging technological advancements. The establishment of a smart mold factory through data-driven engineering, digital twin implementation, and automation in design, machining, and measurements serves as a fundamental approach. It is important to highlight that directly pursuing cost reductions does not contribute to improving productivity and competitiveness. Earlier in 2005, a South-Korean mold manufacturer, Solutec GS, was established in a North-Korean city to make molds with lower labor costs [80,81]. However, as relations between North and South Korea deteriorated, entire industrial complexes in the city were closed in 2016. These days, international mold makers are leaving China as reshoring and nearshoring are promoted by the governments [82]. Now, automation is far more stable and promising than pursuing lower labor costs.
To facilitate such technological progress in mold making, substantial support from research and development (R&D) is essential. This support not only reduces mold-making costs but also leads to a reduction in the workforce. However, the remaining workforce can benefit from increased wages, improved skills, and higher levels of knowledge. This, in turn, enhances the industry’s social image and emphasizes career opportunities.
The transformation of factories through R&D necessitates upskilling and reskilling, which can be achieved by reforming mold-making training programs. This comprehensive approach ensures the industry’s sustainability and profitability while allowing for better control of environmental impacts. Adhering to high regulatory standards, the proposed strategy argues for robust R&D support, contingent on political decisions, to drive the transformation toward smart mold factories. This transformative technological reform is expected to yield economic success and a positive shift in the industry’s social image, considering existing legal and environmental considerations. Consequently, the mold-making industry would become an attractive career option for potential workforce participants. This is how the gap between what the industry requires and what the potential workforce expects can be narrowed. This is depicted in Figure 1.
Based on the analysis, this work suggests the mold-making industry be changed to:
  • The mold-making process should be digitally reconstructed from design to try-out.
  • Attract capable engineers to the industry by increasing wages and suggesting career prospects.
  • The experiential knowledge should be replaced by data-driven approaches and metrics.
  • Mold-making companies need to increase their scale to accumulate design and manufacturing data and secure human resources.
  • Efficient mold making should rely on a small number of skilled engineers to efficiently manufacture many molds by exploiting automation.
In order to attain these objectives, a certain level of automation in mold making should be implemented through the utilization of accumulated data. The succeeding sections provide a description of the feasible technological methods.

5.2. Use of Conventional Software Solutions

Mold makers can improve their design and production processes by leveraging existing IT solutions [83]. They can maximize the potential of CAD/CAM solutions, especially the functions related to automatic generations, such as parametric design and automatic tool path generation [84,85]. For example, the NX software suite from Siemens (NX7 v25.0) can automate mold design and machining [86]. The software automates parts of the mold-development process from design to manufacturing. It can also create a bill of materials, automate repetitive tasks, and design electrodes. The NX CAM programs all milling operations involved in mold manufacturing. The NC programmers work directly from the CAD model and use NX design functions to design electrodes and prepare models for machining. The software also provides open automation and customization tools that enable users to tailor it to specific requirements. Process templates enable NC programmers to use proven cutting methods and tooling. Before executing machining, the NC can be tested by a simulator [75]. This saves time and effort by automating NC programming. It is worth noting that the systems integrate injection molding simulators. Recently, the molding simulators were also embedded into the injection molding machine to support process setup [87].
PLM (product lifecycle management) is a system that manages all the data related to a product throughout its lifecycle, from design to manufacturing to disposal. This data can include CAD files, drawings, test results, and other information [88]. PLM can help improve the efficiency and accuracy of mold making by providing a central repository for all this data [89]. It can also help to improve the efficiency of mold making by providing a central repository for all of the data related to a product. This can save time and reduce the risk of errors [90]. Moreover, it can help improve the accuracy of mold making by providing a single source of truth for all of the data related to a product. This can help to ensure that the mold is designed and manufactured correctly [91].
Although IT solutions like these have already established their presence in various industrial sectors, the overall level of acceptance for them is not high. Whether a mold maker can adopt the latest software system depends on its business size. Traditionally, mold manufacturing was characterized by producing one or a few of the same product, so there were many small companies in the industry. However, as the potential for cost reduction through automation increases, larger companies can lower their unit costs even further, making it more difficult for small companies to compete.

5.3. Digital Twin

As Industry 4.0 emerges, digital twin (DT) is gaining prominence as a crucial tool for smart manufacturing [92,93]. A DT is a virtual representation of a physical object or system [94]. It can be used to simulate the behavior of a physical object or system and to predict how it will perform under different conditions. In mold manufacturing, DTs can be used to improve the efficiency, accuracy, and quality of mold design and manufacturing. They can also be used to optimize the manufacturing process and predict potential problems before they occur. In an ideal scenario, the complete mold manufacturing process, including processing, assembly, and injection molding, should be replicable in a virtual environment. However, even if there are certain limitations or gaps in achieving full reproduction, it is essential to seek assistance in manufacturing through the highest possible level of replication.
DT-based machining is a cutting-edge technique that significantly enhances the efficiency, quality, and cost-effectiveness of machining processes. The process begins by creating an exhaustive model of the machining system, encompassing the CNC machine tool, workpiece, and cutting tool, utilizing advanced CAD/CAM software (Siemens NX2007 v39.0). Real-time data acquisition is crucial for monitoring and optimizing the machining process. To achieve this, sensors and monitoring devices are integrated into the physical machine tool, capturing essential parameters like temperature, vibration, cutting force, and tool wear. The real-time data gathered from the physical machine is consistently synchronized with the DT. This real-time comparison between the virtual model and actual machining conditions provides a live view of the machining operation. By applying sophisticated algorithms and simulation techniques, the DT analyzes the real-time data and simulates diverse scenarios to optimize the machining process. This enables the prediction of potential issues, the evaluation of tool wear, and the fine-tuning of cutting parameters to enhance efficiency and precision.
DT-based machining excels at continuous monitoring and optimization, leading to minimal downtime and heightened productivity. Through virtual simulations and analysis, potential problems are identified proactively, contributing to improved part quality and reduced scrap generation. The streamlining of cutting parameters and reduced downtime enable manufacturers to utilize resources more efficiently, resulting in substantial cost savings. Furthermore, DT-based machining facilitates predictive maintenance by constantly monitoring tool wear and machine condition, effectively preventing unexpected failures. Manufacturers can also leverage DTs to virtually test various design and machining strategies before implementing them in the physical world, thus saving valuable time and resources. Overall, DT-based machining proves to be a potent tool, revolutionizing machining operations by optimizing efficiency, ensuring superior quality, and delivering cost-effectiveness [95].
Conventional machining processes for mass production can be modified and managed using Digital Twins (DTs) to align the physical and virtual realms [96]. However, mold making faces challenges in fully capitalizing on these opportunities, illustrating the difficulty of implementing DT-based machining for molds. DT-based molding, on the other hand, has undergone extensive investigation and development [97,98]. The molding data from the DT can aid in the design of molds [99]. Presently, the development of DT technology in the context of mold making demands a more comprehensive exploration and practical implementation [100]. From a long-term perspective, it is believed that DTs will be necessary to mass-produce high-quality molds with reduced manpower.

5.4. Smart Mold Manufacturing

Smart mold manufacturing is a data-driven approach to mold design and manufacturing [101,102]. The argument that information technology should be introduced into the molding industry has been around for quite some time [103], but it can be seen that the concept of smart manufacturing has incorporated such ideas. Although there is a significant amount of research on smart molding processes, research on smart mold manufacturing is less common [104,105]. It involves the collection, processing, analysis, and use of data from a variety of sources, including cost estimates, design specifications, production parameters, environmental factors, power considerations, and historical test results. The goal of smart mold manufacturing is to improve the efficiency, accuracy, and quality of mold design and manufacturing. By leveraging data, smart mold manufacturing can help to:
  • Shorten delivery times: by identifying and eliminating bottlenecks in the manufacturing process, smart mold manufacturing can help to shorten delivery times.
  • Reduce defect rates: by identifying and correcting design flaws early in the process, smart mold manufacturing can help reduce defect rates.
  • Improve quality: by leveraging data to optimize the manufacturing process, smart mold manufacturing can help to improve the quality of molds.
  • Data collection and processing.
The first step is to collect data from a variety of sources. This data can be collected manually or automatically using sensors and other data-gathering devices. Recent studies focus on data-gathering methods utilizing IoT (Internet of Things) technologies. More specifically, MQTT is considered a prominent protocol for industrial data transmission, while JSON is the suitable data format [106,107]. Once the data is collected, it must be processed to ensure that it is accurate and consistent. The processed data can then be analyzed to identify trends and patterns. This analysis can be used to improve the design of molds, optimize the manufacturing process, and reduce costs. In addition to data analysis, smart mold manufacturing also involves the use of intelligent design tools. These tools can automate the design process, identify potential problems, and suggest design improvements.
A standard mold library can also be used to improve the efficiency of mold design. This library can contain 3D associative design templates, which can be used to create new molds quickly and easily [108]. A data automation system can be used to automate the tasks of data collection, processing, analysis, and utilization. This system can free up engineers and other staff to focus on more strategic tasks. A well-built smart mold manufacturing can be a powerful tool that can be used to improve the efficiency, accuracy, and quality of mold design and manufacturing. By leveraging data, smart mold manufacturing can help to shorten delivery times, reduce defect rates, and improve quality.
The main goal of smart mold manufacturing is to promote the deployment and scaling of data-driven systems by building a robust data circulation structure that improves data utilization and accuracy. This will allow companies to make better decisions, improve their products, and reduce their costs. After accumulating enough data, a machine-learning approach can be employed for mold manufacturing [105,109].

5.5. Additive Manufacturing for Mold Making

Traditional mold making, primarily based on subtractive machining methods, continues to dominate the industry. However, for the last decade, there has been a consistent trend towards adopting alternative manufacturing techniques for mold production. Two notable approaches gaining traction are additive manufacturing and casting [110]. However, despite the technological developments, their implementation in the mold-making industry is still limited. Additionally, mold designers and engineers still consider additive manufacturing as a new technology whose capabilities are not fully demonstrated and are thus concerned with its reliability. If the quality of such molds is guaranteed, it could reduce the number of personnel involved in measurement and polishing, thus decreasing the demand for recruiting technicians. However, the implementation of such technology will also need to rely on the development of educational and workforce development strategies.
In the realm of additive manufacturing, molds are crafted by stacking layers of metal or polymer structures. This method allows for intricate designs and complex geometries to be easily realized. Additionally, 3D printing offers the advantages of lower production costs and improved technological precision, making it an increasingly popular choice for mold fabrication [111]. Another technique involves mold creation through casting. Here, molds are produced by pouring molten materials into a pre-designed mold cavity. Casting enables the production of molds with relatively straightforward geometries, and it finds application in various industries.
The use of 3D printing in mold making is particularly noteworthy due to its cost-effectiveness and technological advancements. As this technology matures and attains higher levels of technical sophistication, it is finding widespread use in mold manufacturing processes. Overall, the industry is witnessing a gradual shift towards exploring and adopting these alternative methods to produce molds. As technology continues to evolve, these approaches are expected to play a more significant role in the mold-making landscape, offering more diverse options to manufacturers seeking efficient and innovative solutions [112].
One of the promising 3D printing technologies used is Direct Metal Laser Sintering (DMLS), sometimes referred to as Selective Laser Melting (SLM). DMLS/SLM is ideal for creating metal molds. In DMLS/SLM, a high-powered laser is used to selectively melt and fuse metal powder, layer by layer, based on a 3D model [113]. This process results in highly dense and fully functional metal parts, making it suitable for creating molds capable of withstanding the high temperatures and pressures involved in various molding processes. It should be noted that the DMLS process allows for the creation of complex molds with conformal cooling [76,114] and gas pressurization [115,116] in a more efficient manner.
The integration of metal additive manufacturing (AM) for conformal cooling in injection molds necessitates the cultivation of novel design skills among mold designers and engineers. Crafting an effective conformal cooling design relies on the engineer’s ingenuity and a profound comprehension of heat transfer dynamics during processing, determining the strategic placement of cooling lines. Moreover, the limitations of surface finishing must be understood and properly considered. Embracing the opportunities presented by technological advancements demands a corresponding commitment to providing comprehensive educational opportunities for the workforce. In tandem with skill development, the utilization of simulation and design automation tools emerges as a critical aspect. These tools become instrumental in optimizing the advantages offered by AM. The synergy between evolving design skills and the strategic use of technological tools not only ensures the successful implementation of AM in mold making but also underscores the pivotal role of continuous learning in harnessing the full potential of this innovative approach.
Other relevant technologies for injection mold making rely on the use of polymer-based additive manufacturing. Despite the reduced mechanical resistance and thermal conductivity [117,118], different polymers have been 3D printed into injection molds [119]. Experimental investigations have demonstrated the feasibility of prototyping and short production runs. Higher performances have been reported when using molds 3D printed with polymer composites. For instance, Fortify3D has developed the technology to 3D print injection molds using fiber-reinforced resins [120]. Overall, 3D-printed mold tooling provides molders with the time and cost benefits of 3D printing while prototyping in end-use material.
Overall, the use of additive manufacturing technologies for mold making requires a workforce with different technical capabilities compared with traditional mold manufacturing, and it is also expected to potentially reduce the number of required personnel. It is expected that the mold industry will increasingly demand personnel who can adapt to changes in associated technologies. At some point, this will reach a stage where simple retraining alone will be insufficient and the pursuit of qualitative changes in the workforce will be inevitable.

6. Outlining the Future of the Mold-Making Industry

Based on the analysis in the previous chapter, the following industrial outlook is anticipated, and it is considered that the following educational reform and public support will be necessary for this.

6.1. Industrial Outlook

The mold-making industry is a fragmented market, with many small and medium-sized companies. The majority of these companies are low-profitable and have low global competitiveness. However, there are a few larger companies that are highly profitable and have high global competitiveness. These companies operate in different ways. Low-profitable companies typically have labor-intensive factories with a large number of employees. Their income per employee is medium, and their automation level is low. The workforce education in these companies is typically technology-based, and the training requirements are lengthy and intensive. The high-profitable companies, on the other hand, operate smart factories with a small number of employees. Their income per employee is high, and their automation level is high. The workforce education in these companies is typically science-based, and the training requirement is minimal. The differences in profitability and global competitiveness between these two groups of companies are due to a number of factors, including the level of automation, workforce education, and the training requirement. The low-profitable companies are less able to compete in the global market because they are not as efficient or productive as the high-profitable companies. However, the mold-making industry is undergoing a transformation, with more and more companies adopting automation and science-based workforce education [121]. This is leading to a more competitive market, with the high-profitable companies becoming even more profitable and the low-profitable companies becoming more competitive [122]. The outlook presented in this discussion is summarized in Table 2.

6.2. Educational Reform

Mold-making organizations need to undergo a transformation, shifting their focus from traditional tasks such as machining, measuring, and testing to automated data-driven systems and updating digital twin models. In addition to possessing the essential skills for mold design and manufacturing, these organizations must adapt to the rapid changes in the industry. As automation becomes increasingly prevalent and digital twin models are introduced, mold-making organizations must keep pace with these advancements and acquire the necessary expertise. Employees who can effectively manage automated systems and update digital twin models will assume a pivotal role in the industry. Their proficiency will lead to greater efficiency in mold design and manufacturing, resulting in improved mold quality and increased productivity. However, if we fail to cultivate and supply a workforce capable of handling these tasks, the skill gap will remain unaddressed, impeding the smooth progress of industrial reform.
To contribute to the development of the mold industry, organizations must embrace these changes and prioritize skill acquisition. Adapting to automated systems and digital twin technologies will not only enhance their competitive edge but also foster innovation and excellence within the industry. In summary, mold-making organizations need to evolve their skill sets and capabilities to encompass managing automated systems and working with digital twin models as shown in Table 3. By doing so, they will play a crucial role in making mold design and manufacturing more efficient, leading to higher-quality molds and increased productivity, ultimately contributing to the overall growth and advancement of the industry.

6.3. Public Support

The mold-making industry has gained global recognition for its vital importance, leading governments worldwide to provide various forms of support to this sector. This support includes grants, loans, tax incentives, research and development funding, and trade promotion. While the specifics of this support may vary among countries, the commitment to fostering the industry’s growth remains consistent across governments. Additionally, non-governmental organizations play a crucial role in supporting the mold-making industry by offering diverse services such as training, networking opportunities, and advocacy, which significantly contribute to the success of mold-making businesses.
Government support for the mold-making industry can be observed in different countries. For instance, in the United States, the Department of Commerce’s Manufacturing Extension Partnership (MEP) offers vital technical assistance and training to mold-making businesses. Similarly, South Korea’s government has established the Mold Technology Support Center (MTSC) to provide training and essential resources to mold-making businesses.
While mold-making technology is essential not only in general manufacturing but also in crucial sectors like defense, healthcare, and agriculture, it also becomes the backbone of national organizations or economic defense alliances that must be maintained regardless of profitability. Therefore, compared with other industrial technologies, mold making holds a special status, leading many countries to support this industry and its technologies in the public domain. However, as mentioned earlier, the support provided to small and medium-sized enterprises to sustain their businesses and promote substantial growth or technological advancements is somewhat limited. This kind of subsidized support is insufficient to bring about meaningful reform.
Government-led support for the mold-making industry should focus on the advancement of technology, automation, and the enhancement of workforce skills. This will help the industry become more innovative, competitive, and sustainable in the global market. Specifically, the government should encourage investments in research and development, provide specialized training programs for the workforce, offer incentives for collaboration between mold-making companies and research institutions, promote knowledge-sharing platforms and industry events, and support the establishment of technology centers and innovation hubs dedicated to mold-making. By taking these steps, the government can help the mold-making industry undergo a transformative shift, becoming more research- and development-oriented and less reliant on manpower. This will ultimately lead to the creation of new technologies, improved production processes, and enhanced product quality. Table 4 describes the desirable changes in public support asserted by this study.

7. Conclusions

The mold-making industry confronts tight workforce supply and technological challenges globally. Staying competitive demands investments in talent attraction, skills gap bridging, and technology adoption. Our review of the mold-making and engineering industries delved into characteristics, challenges, demographics, and prospects. The work provided a comprehensive analysis of the impacts on economic and environmental sustainability.
In the context of reshoring, the mature industry grapples with productivity constraints, substantial hiring/training burdens, and an experiential knowledge dependency. Competitiveness can be bolstered through digital transformation, wage increases, data-driven approaches, operational streamlining, and automation prioritization.
A panel discussion with global experts revealed successful workforce strategies encompassing diversity targeting, global workforce integration, culture enrichment, and training investments. Implementing these strategies can equip the industry to thrive amid rapid market evolution.
From a technology perspective, the increased adoption of automation and Industry 4.0 technologies will be critical to ensuring continued growth. However, educational programs at different levels must evolve to support hands-on training, simulation, data analysis, and robotics.
While governments and non-governmental support are vital, governments should emphasize technological advancement and workforce development. Mold-making entities must pivot toward automation and digital twin models for efficiency and competitiveness. Embracing these shifts fosters innovation and industry expansion. In sum, with the right strategies, the mold industry can continue its leadership in the global economy.

Author Contributions

Conceptualization, D.M. and S.K.K.; methodology, D.M. and S.K.K.; validation, S.K.K. and D.M.; investigation, D.M. and S.K.K.; resources, D.M. and S.K.K.; writing—original draft preparation, D.M. and S.K.K.; writing—review and editing, D.M. and S.K.K.; project administration, S.K.K.; funding acquisition, D.M. and S.K.K. All authors have read and agreed to the published version of the manuscript.


This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (NRF-2018R1A5A1024127 and NRF-2020R1I1A2065650). This work was also supported by the University of Massachusetts Lowell Provost Office Start-Up Funds for D.M.

Data Availability Statement

No new data were created or analyzed in this study. Data sharing is not applicable to this article.

Conflicts of Interest

The authors declare no conflict of interest.


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Figure 1. Derived scheme from the PESTLE analysis.
Figure 1. Derived scheme from the PESTLE analysis.
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Table 1. Projected Employment Trends in Machining Sectors from 2021 to 2031 [66].
Table 1. Projected Employment Trends in Machining Sectors from 2021 to 2031 [66].
Occupational TitleEmployment, 2021Projected Employment, 2031Change, 2021–2031
Metal and plastic machine workers1,014,000968,100−5−45,900
Extruding and drawing machine setters, operators, tenders, metal, and plastic60,60061,0001400
Forging machine setters, operators, tenders, metal, and plastic11,8009600−18−2200
Rolling machine setters, operators, tenders, metal, and plastic32,10028,700−11−3500
Cutting, punching, press machine setters, operators, tenders, metal, and plastic183,300170,100−7−13,200
Drilling and boring machine tool setters, operators, tenders, metal, and plastic69005600−19−1300
Grinding, lapping, polishing, buffing machine tool setters, operators, tenders, metal, and plastic69,00063,000−9−6100
Lathe and turning machine tool setters, operators, tenders, metal, and plastic20,00018,200−9−1800
Milling and planning machine setters, operators, tenders, metal, and plastic15,20012,500−18−2700
Metal-refining furnace operators and tenders15,90014,900−6−1000
Pourers, casters, metal67005900−13−800
Model makers, metal, and plastic38003500−7−300
Patternmakers, metal, and plastic21001900−10−200
Foundry mold and coremakers14,00012,400−11−1600
Molding, core making, casting machine setters, operators, tenders, metal, and plastic166,100165,200−1−900
Multiple machine tool setters, operators, tenders, metal, and plastic139,500143,40034000
Welding, soldering, brazing machine setters, operators, and tenders32,30029,700−8−2600
Heat treating equipment setters, operators, tenders, metal, and plastic14,90013,500−10−1500
Plating machine setters, operators, tenders, metal, and plastic33,00029,600−10−3400
Computer numerically controlled tool operators160,400147,600−8−12,800
Computer numerically controlled tool programmers26,20031,800215500
Table 2. Prospects of mold-making industry.
Table 2. Prospects of mold-making industry.
MarketMany companies with low profitability and low global competitivenessFewer companies with high profitability and high global competitiveness
OperationsLabor-intensive factorySmart factory
Number of employeesLarge to MediumSmall
Income per employeeMediumHigh
Automation levelLowHigh
Workforce educationTechnology-basedScience-based
Training requirementLengthy and intensiveMinimal
Quality controlExperience basedData-driven
Table 3. Change in educational content.
Table 3. Change in educational content.
Part and Mold design, CADExperience-based, iterativeAutomated modeling
Mold Manufacturing, CAMManual and human-centric programming of toolpaths, machine- and tool-specificAutomated toolpath programming and optimization
Process Simulation, CAEIterative part and mold design, time-constrainedDigital twin, AI-based optimization
Process EngineeringOperation of the molding machine process window development and validation through lengthy experimentationData processing from the machine and closed-loop processing
Quality controlMetrology and polishingData-based precision control
Table 4. Public support transition for mold-making industry.
Table 4. Public support transition for mold-making industry.
EducationalSkilled workforce training programs (vocational, apprenticeship or internships)Program for small number of elite engineers
FinancialTax incentives, grants, or low-interest loansReduced incentives
TechnicalTechnical consultingSupport for automation
toward smart mold factory
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Masato, D.; Kim, S.K. Global Workforce Challenges for the Mold Making and Engineering Industry. Sustainability 2024, 16, 346.

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Masato D, Kim SK. Global Workforce Challenges for the Mold Making and Engineering Industry. Sustainability. 2024; 16(1):346.

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Masato, Davide, and Sun Kyoung Kim. 2024. "Global Workforce Challenges for the Mold Making and Engineering Industry" Sustainability 16, no. 1: 346.

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