Custom Plastic Injection Molding Service

The injection molding process is known for its speed and efficiency. The entire cycle for producing a single part typically lasts between 2 seconds to 2 minutes, depending on several factors such as the complexity of the part, the size of the mold, and the specific machine settings used.

1. Cycle Time: For simpler parts, the injection and cooling phases can be completed in as little as 2 seconds. However, for larger or more complex components, the process may take up to 2 minutes to ensure proper filling and cooling.
2. Factors Influencing Time: The cycle time can vary based on:
   • Part Complexity: More intricate designs require longer cooling times.
   • Mold Size: Larger molds generally take longer to process due to the increased volume of material and cooling requirements.
   • Machine Settings: Different machines and settings can affect the speed of injection and cooling phases.

Injection molding cycle time refers to the total time it takes to complete one full cycle of the injection molding process, from the moment the mold closes until it opens again to eject the finished part. This cycle time is a critical factor in determining the efficiency and productivity of the injection molding operation.

Components of Cycle Time

The injection molding cycle time is typically composed of several key elements:

1. Fill Time: This is the time taken to inject the molten plastic into the mold cavity. It is influenced by factors such as the viscosity of the material and the design of the mold.
2. Pack and Hold Time: After the mold is filled, the material is packed into the cavity to compensate for shrinkage as it cools. This phase ensures that the part maintains its shape and dimensions.
3. Cooling Time: This is often the longest part of the cycle and involves allowing the injected material to cool and solidify within the mold. The cooling time is crucial for achieving the desired mechanical properties and surface finish of the part.
4. Mold Open Time: Once the part has cooled sufficiently, the mold opens to allow for ejection. This phase includes the time taken for the mold to separate and for any ejection mechanisms to operate.
5. Ejection Time: This is the time required to eject the finished part from the mold. It can vary depending on whether manual or automated ejection methods are used.

Importance of Cycle Time

Cycle time is a vital metric in injection molding as it directly impacts production rates and overall manufacturing costs. Shorter cycle times can lead to increased productivity and lower costs per part, making it essential for manufacturers to optimize this aspect of the injection molding process. Factors such as part design, material selection, and mold design can all influence cycle time, and understanding these relationships is key to improving efficiency in production.

The time it takes to create an injection mold can vary significantly based on several factors, including the complexity of the part, the type of mold, and the manufacturing processes involved. Here are some general timelines:

1. Simple Molds: For straightforward designs, the manufacturing process can take as little as two weeks. This is typically applicable for simple plastic parts that do not require intricate details.
2. Standard Molds: For most molds, especially those that are moderately complex, the timeline is usually around 4 to 8 weeks. This timeframe is common for a significant portion of molds produced in the industry.
3. Complex Molds: More complex molds can take longer, often ranging from 3 to 5 months to complete. This extended timeframe accounts for the additional design, engineering, and testing required to ensure precision and functionality.
4. Prototype Molds: If prototype molds are needed for testing or development purposes, they can typically be built within 1 to 3 months, depending on the specific requirements and adjustments needed during the prototyping phase.

In summary, while simple molds can be produced relatively quickly, more complex molds require additional time for design and manufacturing, often extending the lead time to several months.

The cost of injection molding can vary significantly based on several factors, including the complexity of the mold, the materials used, and the production volume. Here’s a breakdown of typical costs associated with injection molding:

1. Mold Costs: The cost of creating an injection mold can range widely. Simple, single-cavity molds may cost between $1,000 and $5,000, while larger, more complex molds can range from $4,500 to $16,000. For high-production, multi-cavity molds, costs can escalate to $25,000 to $50,000 or even exceed $80,000 for very intricate designs.
2. Setup Costs: Initial setup costs can be substantial, often reaching up to $100,000 for complex molds designed for high-volume production. This includes design, manufacturing, and any necessary adjustments to ensure quality.
3. Variable Costs: Once the mold is created, the variable costs associated with the injection molding process are relatively low. This is due to the efficiency of the process, which allows for the production of large quantities of parts at a lower cost per unit.
4. Overall Budgeting: For a comprehensive project, such as developing a new product, budgeting around $250,000 for manufacturing costs, including tooling and production, is common for serious endeavors.

Injection molding employs various types of molds, each designed to meet specific production needs and part characteristics. Here are some of the most common types of molds used in the injection molding process:

1. Two-Plate Molds: This is the most common type of injection mold. It consists of two main plates that form the mold cavity. When the mold is closed, the two plates come together to create the shape of the part. This design is straightforward and cost-effective, making it suitable for many applications.
2. Three-Plate Molds: In a three-plate mold, there are three plates involved: the front plate, the back plate, and a middle plate. This design allows for the separation of the runner system from the part, which can be beneficial for reducing waste and improving the quality of the final product. It is often used for more complex parts.
3. Family Molds: Family molds are designed to produce multiple parts simultaneously, where different parts are molded in a single cycle. This type of mold is efficient for producing small, similar parts and can help reduce production time and costs.
4. Hot Runner Molds: These molds use a heated runner system that keeps the plastic in a molten state, reducing waste and improving cycle times. Hot runner molds are ideal for high-volume production as they eliminate the need for a cold runner system, which can create excess scrap material.
5. Cold Runner Molds: In contrast to hot runner molds, cold runner molds use a runner system that cools and solidifies the plastic before it reaches the cavity. This type is simpler and less expensive but can result in more waste due to the need to remove and recycle the solidified runners.
6. Overmolding Molds: Overmolding involves molding one material over another, allowing for the creation of multi-material parts. This type of mold is used to combine different materials, such as soft and hard plastics, to enhance functionality and aesthetics.
7. Insert Molds: Insert molds are designed to accommodate pre-formed components, such as metal inserts or other plastic parts, which are placed into the mold before the injection process. This allows for the integration of different materials and functionalities within a single part.

Each type of mold has its advantages and is chosen based on factors such as part complexity, production volume, and material requirements. Understanding these options can help in selecting the most suitable mold for your specific injection molding project.

The primary distinction between single-cavity and multi-cavity molds lies in their design and production capabilities:

1. Single-Cavity Molds:
   • A single-cavity mold contains only one cavity, which means it produces one part per injection cycle. This type of mold is often used for parts that are complex or require high precision, such as medical devices or specialized components.
   • Single-cavity molds are ideal for low-volume production runs or when detailed attention to the part's design is necessary. They allow for greater control over the molding process, which can be beneficial for intricate designs.
2. Multi-Cavity Molds:
   • In contrast, multi-cavity molds have multiple cavities, enabling the production of several identical parts simultaneously in a single injection cycle. This design significantly increases production efficiency and reduces the cost per unit, making it suitable for high-volume manufacturing.
   • Multi-cavity molds are advantageous for mass production, as they can produce large quantities of parts in a shorter time frame, thus optimizing the manufacturing process.

In summary, the choice between single-cavity and multi-cavity molds depends on the production volume, complexity of the parts, and the specific requirements of the project. Single-cavity molds are best for precision and low-volume needs, while multi-cavity molds excel in high-volume production scenarios.

The lifespan of an injection mold can vary widely based on several factors, including the materials used, the complexity of the mold, the type of production, and the operating conditions. Here are some key points regarding mold lifespan:

1. Material Influence:
   • Steel Molds: Molds made from high-quality hardened steel can typically last for several hundred thousand to well over a million cycles. These molds are designed for high-volume production and are known for their durability and resistance to wear.
   • Aluminum Molds: In contrast, aluminum molds are generally used for lower-volume production and prototyping. Their lifespan can range from 2,000 to 10,000 cycles, depending on the specific type of aluminum and the part design.
2. Mold Classification:
   • Molds are often classified based on their intended use and expected lifespan. For example, Class 103 molds are suitable for medium-level production and can last up to 500,000 cycles, while Class 104 molds, designed for prototyping and low-volume runs, may last up to 100,000 cycles.
3. Operating Conditions: The conditions under which the mold operates significantly affect its lifespan. Factors such as temperature, pressure, and the type of plastic being molded can influence wear and tear on the mold.
4. Maintenance: Regular maintenance and proper care can extend the lifespan of an injection mold. This includes routine inspections, cleaning, and addressing any defects that may arise during production.

In summary, while the lifespan of an injection mold can vary greatly, high-quality steel molds can endure for hundreds of thousands to millions of cycles, whereas aluminum molds are more suited for shorter production runs with a lifespan of a few thousand cycles. Proper maintenance and operating conditions play a crucial role in maximizing the mold's longevity.

The materials used to create injection molds are crucial for ensuring durability, precision, and the ability to withstand the high pressures and temperatures involved in the injection molding process. Here are the most common materials used for making injection molds:

1. Steel: Steel is the most widely used material for injection molds due to its strength, durability, and resistance to wear. There are different types of steel used, including:
   • P20 Steel: A pre-hardened steel commonly used for medium-volume production.
   • H13 Steel: A hot work tool steel known for its toughness and heat resistance, ideal for high-temperature applications.
   • S7 Steel: A shock-resistant steel often used for molds that require high impact resistance.
2. Aluminum: Aluminum molds are lighter and easier to machine than steel molds, making them suitable for low to medium production runs. They offer faster turnaround times and are often used for prototyping or short production runs.
3. Copper Alloys: Copper is sometimes used in molds for its excellent thermal conductivity, which helps in cooling the molded parts more efficiently. Copper alloys can be combined with other materials to enhance their properties.
4. Beryllium-Copper Alloys: These alloys provide a good balance of strength and thermal conductivity, making them suitable for molds that require efficient heat transfer.

Choosing the right material for an injection mold depends on factors such as the production volume, the complexity of the part, the required precision, and the budget. Each material has its advantages and disadvantages, making it essential to consider the specific needs of the project.

Undercuts in injection molding are features on a part that prevent it from being directly ejected from the mold along the parting line. These features, such as side holes, slots, threads, or protrusions, add complexity to the mold design and manufacturing process. Here's how undercuts affect mold design:

1. Increased Mold Complexity:
   Undercuts require additional mechanisms or design considerations to allow for the proper release of the part from the mold. For example, side-action cams, lifters, or inserts may be needed to address these features.
2. Higher Costs:
   The inclusion of undercuts generally increases the overall cost of the mold. This is due to the need for more intricate mold components, additional machining, and longer design and manufacturing times.
3. Part Ejection Challenges:
   Undercuts can prevent the part from being ejected directly along the mold's parting direction. This necessitates the use of specialized mechanisms, such as side cores or collapsible cores, to release the part without damaging it.
4. Design Adjustments:
   In some cases, part designs may need to be modified to avoid undercuts altogether. This can involve redesigning features like threads, snaps, or vents to simplify the mold and reduce costs.
5. Material Considerations:
   The type of material being molded can influence how undercuts are handled. For example, softer materials like silicone can tolerate larger undercuts because they are more flexible and less likely to break during ejection.
6. Precision Requirements:
   Addressing undercuts requires precise engineering and tooling. Mechanisms like side actions or lifters must be carefully designed and manufactured to ensure they function correctly without compromising the mold's durability or the part's quality.

Undercuts add complexity to mold design, requiring additional mechanisms, higher costs, and careful engineering to ensure successful part ejection. While they enable the creation of intricate features, designers often weigh the benefits of including undercuts against the increased costs and challenges they introduce.

Yes, recycled plastics can be used in injection molding. This practice is becoming increasingly common as manufacturers seek to reduce waste and minimize environmental impact. Here are some key points regarding the use of recycled plastics in this process:

1. Material Types: Various types of recycled plastics, such as recycled ABS, polypropylene, and polyethylene, can be utilized in injection molding. These materials are often sourced from post-consumer products or manufacturing by-products.
2. Quality and Performance: Recycled plastics can perform comparably to virgin materials in many applications. When processed correctly, they can maintain the necessary strength and durability required for the final products. In fact, using recycled plastic in injection molding has shown no significant negative impact on the quality of the manufactured parts.
3. Recycling Process: The process involves melting down the recycled plastics and injecting them into molds to create new products. This not only helps in reducing the amount of plastic waste but also lowers the demand for virgin plastic materials.
4. Challenges: While there are many benefits, using recycled plastics can present challenges, such as variations in material properties and potential contamination. Manufacturers need to ensure that the recycled materials are clean and uncontaminated to achieve the desired quality in the final products.
5. Environmental Impact: Utilizing recycled plastics in injection molding contributes to a more sustainable manufacturing process by reducing the reliance on new plastic production and minimizing landfill waste.

Here are some of the most common plastics used in the injection molding process:

1. Acrylonitrile Butadiene Styrene (ABS): ABS is widely used due to its excellent impact resistance, toughness, and ability to be easily molded. It is commonly found in consumer products, automotive parts, and electronic housings.
2. Polypropylene (PP): Known for its versatility, polypropylene is lightweight, chemical-resistant, and has good fatigue resistance. It is often used in packaging, automotive components, and household items.
3. Polyethylene (PE): This is one of the most common thermoplastics, available in various densities (e.g., HDPE, LDPE). It is used in products like bottles, containers, and toys due to its flexibility and chemical resistance.
4. Nylon (Polyamide): Nylon is valued for its strength, durability, and resistance to wear and abrasion. It is commonly used in automotive parts, industrial applications, and consumer goods.
5. Polycarbonate (PC): Known for its high impact resistance and optical clarity, polycarbonate is used in applications such as eyewear lenses, safety equipment, and electronic components.
6. Polystyrene (PS): This plastic is often used for disposable cutlery, containers, and packaging materials. It is lightweight and can be easily molded into various shapes.
7. Polyoxymethylene (POM): Also known as acetal, POM is known for its high strength, stiffness, and low friction properties. It is commonly used in precision parts, gears, and automotive applications.
8. Acrylic (PMMA): Acrylic is valued for its clarity and weather resistance. It is often used in applications requiring transparency, such as displays and lighting fixtures.

Selecting the right plastic for your part is a critical step in ensuring the success of your project. The choice depends on several factors, including the part's intended use, environmental conditions, and mechanical requirements. Here are some key considerations to guide your decision:

1. Understand the Purpose of the Part
   Consider the function of the part and any mechanical properties it needs to provide. For example, does it need to withstand high stress, provide flexibility, or resist impact? Understanding the part's role will help narrow down suitable materials.
2. Evaluate Environmental Conditions
   Assess the conditions the part will be exposed to, such as temperature, humidity, UV exposure, or chemicals. For instance, if the part will be used outdoors, UV-resistant plastics like polycarbonate or acrylic may be ideal. For chemical resistance, materials like polypropylene or polyethylene are often recommended.
3. Consider Structural Requirements
   Determine the stresses, weight, and pressure the part will encounter. For parts requiring high structural integrity, materials like PEEK, polyoxymethylene (POM), or glass-filled plastics are often suitable.
4. Surface Finish and Aesthetics
   If the appearance of the part is important, consider plastics that offer a smooth surface finish or can be easily colored. ABS, for example, is commonly used for consumer products due to its excellent surface finish and ease of customization.
5. Regulatory and Safety Requirements
   If the part will come into contact with food, beverages, or medical applications, ensure the material is food-grade, biocompatible, or meets relevant safety standards. PET is a popular choice for food packaging, while medical-grade plastics like polycarbonate are used for medical devices.
6. Cost and Volume
   Budget constraints and production volume also play a role. For high-volume production, cost-effective materials like polypropylene or polyethylene may be ideal. For low-volume or specialized applications, higher-cost engineering plastics like nylon or PEEK might be justified.
7. Consult Experts
   With over 85,000 commercial plastic options available, consulting with a plastic expert or supplier can help you make an informed decision. They can recommend materials based on your specific requirements and guide you through the selection process.

Yes, injection molding can be effectively used for prototyping. This method allows manufacturers to create production-like prototypes that closely resemble the final product in terms of material properties and dimensional accuracy. Here are some key points about using injection molding for prototyping:

1. Rapid Production: Injection molding can produce prototypes quickly, often within weeks. This speed is beneficial for testing designs and making necessary adjustments before moving to full-scale production.
2. Material Versatility: Prototype injection molds can utilize various materials, including softer metals like aluminum or semi-hardened steel, which can be more cost-effective for short runs compared to traditional hardened steel molds.
3. Functional Testing: Prototyping with injection molding allows for functional analysis and testing of the parts. This helps identify any design flaws or issues with fit and function early in the development process, enabling engineers to make informed decisions before committing to mass production.
4. Cost-Effectiveness: While there may be initial costs associated with creating injection molds, using this method for prototyping can lead to long-term savings. It allows for the identification and correction of issues before investing in larger production runs.
5. High Accuracy: Injection molding provides high precision and repeatability, making it suitable for prototypes that require exact specifications and tolerances.

In summary, injection molding is a viable and efficient option for prototyping, offering benefits such as speed, material flexibility, and the ability to conduct thorough testing of designs before full-scale production. If a multi-cavity mold is desired, one cavity can be cut for the prototype while leaving room for additional cavities later.

Doyle Shamrock Industries has been a key player in the plastic injection molding industry since its establishment in 1975. The company operates out of Holland, Ohio, and boasts a substantial facility that spans 200,000 square feet, designed to meet diverse injection molding production needs.

Certifications and Quality Assurance

The company is recognized for its commitment to quality, holding ISO 14001-2015 and ISO 9001:2015 certifications. This ensures that they adhere to rigorous standards in both environmental management and quality management systems.

Custom Injection Molding Services Offered

Doyle Shamrock Industries provides a comprehensive range of services, making it a one-stop-shop for clients. Their offerings include:

• Plastic part design
• Injection mold design
• Mold building
• Part production

Engineering and Manufacturing Capabilities

The engineering department is well-equipped to handle both plastic part and mold design, while the machine shop features advanced capabilities such as:

• Complete mold build
• Mold maintenance and repair
• CNC lathe and milling machines
• EDM equipment
• Ultrasonic Welding

Facilities and Distribution

In addition to the two manufacturing locations, Doyle Shamrock Industries also operates an off-site warehouse and distribution facility, enhancing their logistical capabilities. Overall, Doyle Shamrock Industries stands out as a full-service provider in the plastic injection molding sector, dedicated to customer satisfaction and high-quality production.

Corporate Quality Policy

Provide our customers a high quality product that is shipped on time. We will continually evaluate and improve our product through the Quality Management System (QMS).