Knowledge Base

Plastic Injection Molding Machine Knowledge Base

The ICOMold Knowledge Base provides information on plastic injection mold processes and various topics related to plastic molding and plastic tooling. Download the Design Guide below or read on to learn more about plastic molding. The Design Guide will help you avoid costly and time-consuming design mistakes. The guide provides essential information on important requirements that should be incorporated at the initial design stage. Click here to download the guide.

What is Plastic Injection Molding?

Plastic injection molding is a manufacturing process used to make a variety of plastic parts, typically at high volumes, for a wide range of industries. Plastic resin pellets are melted and then the liquefied plastic is forced into a metal mold cavity. After cooling, the mold is opened, the part is ejected, and the process is ready to start again. Plastic molding is ideal for producing thousands, hundreds of thousands, or even millions of the same part or part set.

What is the Plastic Injection Molding Process?

The injection molding process starts with a Computer Aided Design (CAD) file that contains a digital version of the part. The CAD file is used as a blueprint to create the metal mold, also known as the tooling. The mold is typically comprised of two halves with the design machined into the middle of the two pieces. The mold is then placed into the injection molding machine. Plastic material, in the form of small pellets, is poured into a hopper on the machine. The pellets then move to a heating chamber where the plastic is melted. The molten plastic is forced into the mold once it has reached the right temperature. A screw or a ram mechanism controls the pressure and speed of the injected material. The short phase between the injection and the cooling of the object into its solid form is referred to as the dwelling phase. This step ensures that the mold cavities are completely filled before cooling begins. After the part has cooled, the mold is opened and the part is ejected. The mold is then closed and the process can start over. Learn more about the basics of plastic injection molding.

Advanced Plastic Injection Molding Processes

The plastic molding process has nearly limitless applications. Carrying bags, packaging material, beverage bottles, accessories for the computer, automotive parts, and toys can all be manufactured using advanced plastic molding technology. Plastic injection molding technology is capable of manufacturing complex parts of the highest quality. Learn more about the advanced plastic injection molding processes.

Injection Molded Plastic Part Design Guidelines

To help avoid costly and time-consuming design mistakes, we created a plastic injection molding design guide. It provides information on the most important design requirements so they can be incorporated at the initial design stage. The sample tips below illustrate the type of information provided in the complete guide. Click here to download the guide.

Calculate Cooling System In Injection Molding

The cooling process starts after the molten plastic is injected into the mold. Cooling can account for nearly two-thirds of the cycle time for each part. Calculating and then optimizing cooling time is a critical part of the injection molding process, saving the customer time and money. Cooling also has a major impact on both the quality of the part and the productivity of the mold. Improper or non-uniform cooling will cause defects like stresses, shrinkage, and warping. Improper cooling can also shorten the lifecycle of the mold. Learn more about the plastic injection cooling process.

Conformal Cooling

ICOMold by Fathom now offers Conformal Cooling technology. Cooling lines can be manufactured directly into the tooling with Direct Metal Laser Sintering (DMLS). This process uses metal powder to 3D print molds. Learn more about. Conformal Cooling or the DMLS Process. 

Calculate Plastic Mold Shrinkage

Shrinkage is the contraction of a plastic part as it cools after injection molding. Shrinkage is normal and can be calculated based on a variety of factors including the mold size and the chosen plastic material. Most of the shrinkage occurs in the mold while the part is cooling. A small amount of shrinkage occurs after ejection. Some parts may continue to shrink slightly for several hours or days until the temperature and moisture content stabilize. Learn more about plastic molded part shrinkage.

Clamping Force or Clamping Tonnage

There are three main parts in an injection molded plastics machine – the mold, the clamping unit, and the injection unit. The clamping unit holds the mold closed during the plastic injection and the cooling process. Clamping force, also known as clamping tonnage, is the amount of pressure applied to the mold during the injection molding process. Proper clamping force calculations are a critical part of injection molding. The correct amount of pressure must be applied to the mold in order to keep it closed and prevent damage to the part and the mold. Too much force, however, can damage the mold and result in part defects. Learn more about plastic injection clamp tonnage.

Custom Injection Molding Thermoplastic

Thermoplastic materials make up the majority of the plastic items that we use everyday. Injection molded products can be found in every home, school, and office. These products include plastic bags, consumer packaging, cell phone case, disposable cutlery, automotive parts, computer components, and more. Injection molding can be used to manufacture replacement parts or create custom parts or new products. Learn more about thermoplastics.

Gas Assist Injection Molding

Gas assist injection molding is a process that utilizes an inert gas to create one or more hollow channels within the injection-molded plastic parts. At the end of the filling stage, the gas is injected into the still liquid core of the molding. This creates hollow areas during the injection molding process. Learn more about gas assist injection molding.

Instant Quote

ICOMold by Fathom offers instant online quoting for custom plastic injection molding and CNC machined parts. Our system gives customers fast access to quotes and provides the ability to interactively manage the project online once it has begun. See how in six steps you can turn your CAD file into a finished product.

What is Mold Manufacturing?

The mold, or tooling, is at the center of the plastic injection molding process. The mold will also make up the majority of cost associated with injection molding. ICOMold by Fathom has decades of mold machining experience. As part of the Fathom Digital Manufacturing network, ICOMold has access to advanced machining and additive technology that can improve mold lifecycles and output. ICOMold machines all molds out of high quality steel. Steel molds are typically more expensive than aluminum molds, however, steel will last longer and can be repaired or changed with welding. Aluminum molds do not last as long and must be remade if they are damaged or changes are required. Read more about mold manufacturing.

What are Examples of Injection Molding Products?

Injection molding is a popular manufacturing process used to make many of the items we use every day. If an object is made of plastic, there is a good chance it was made using injection molding. Commercial, consumer, and industrial goods all use injection molding to produce products. Injection molding offers businesses the opportunity to create a custom design with details that are unique to their brand. Read more about examples of Injection Molding Products.

What is 3D Molding?

3D molding is a method of injection molding that utilizes a plastic mold made by a 3D printer. While a traditional steel or aluminum injection mold is ideal for mass production, a 3D mold may be an alternative for prototypes or projects that require lower volumes. Read on to discover if 3D molding is the best choice for your job. Read more about 3D Molding.

What is a 3D Printed Injection Mold?

Additive technologies, like 3D printing, can be used to make molds and mold components for certain projects. 3D molding uses a plastic, 3D-printed mold for injection molding purposes. 3D molding works well for prototyping or very low volume runs. 3D printed molds are easy to make and inexpensive, the downside is they molds are not durable and will not hold up to the rigors of injection molding. A metal mold will be required for anything beyond a handful of parts.

Additive technologies like Direct Metal Laser Sintering (DMLS) can be used to 3D print metal molds and metal components for use in higher production injection molding proejcts. As part of Fathom Digital Manufacturing network, ICOMold has access to advanced and conventional machining methods that can meet the needs of any project. 

Read more about using a3D Printed Injection Mold or visit the Fathom website to learn about the wide range of additive technologies available through Fathom Digital Manufacturing.  

What is ABS Injection Molding?

Acrylonitrile butadiene styrene (ABS) is a rigid product that is lightweight, durable, and an excellent choice for many injection-molding projects. A few popular items made from ABS include appliances, toys, medical supplies, musical instruments, computer parts, and more. The experts at ICOMold have decades of experience with ABS injection molding and can provide you with a seamless process from prototype to production. Read more about ABS Injection Molding

What is an Injection Molding Press?

Injection molding press is another name for an injection-molding machine. These machines are used to manufacture plastic parts with the injection molding process. Injection molding machines are highly efficient and can produce thousands, hundreds of thousands, even millions of parts from the same mold. Read more about Injection Molding Press

Liquid Silicone Molding 101

Liquid silicone rubber (LSR) products can be used in a variety of ways. Seals, electric connectors, kitchen items, and baby products, are all made of silicone rubber. Silicone is a popular material because it can maintain its mechanical properties over a wide range of temperatures, from freezing to extreme heat. Silicone will also repel water. The process of producing a LSR part is similar to that of other thermoplastic parts. Read more about Liquid Silicone Molding 101

Micro Molding 101

Micro molding is a unique form of injection molding that requires extreme precision. Micro molding is a plastic molding process used to make very small parts or components. Micro molding, like most injection molding, uses a metal mold with a cavity that dictates the shape of the part. Micro molding requires an advanced level of knowledge to ensure the successful production of very small parts. Monitoring temperature, pressure, and material characteristics are critical to the success of the process. Micro molding is utilized by multiple industries for products like medical devices, telecom fiber optics, automotive parts, and more. Read more about Micro Molding 101

What is HDPE Molding?

High-density polyethylene (HDPE) is a commonly used plastic in the injection molding process. HDPE has good chemical and impact resistance. It is also relatively inexpensive. There are many applications for HDPE plastic across a variety of industries, from consumer products to industrial or commercial use. Read more about HDPE Molding

What is Mold Tooling?

The metal mold at the heart of the injection molding process is also known as the tooling. Mold tooling may also refer to the machining process used to make these molds. The right mold tooling is an important part of producing a premium end product. ICOMold by Fathom selects premium components and materials for all of its plastic tooling. All high-production metal molds will be made with high-quality steel. Steel tooling, while typically more expensive than aluminum tooling, will last longer, is easier to repair, and will ultimately save the customer money over an extended production run. Read more about Mold Tooling

What is Polymer Molding?

A polymer is a natural or synthetic material made up of a long chain of repeating molecule groups. Many materials can be classified as a polymer including cellulose, silk, wool, and plastic. Polymer will almost exclusively refer to plastic materials when used in the context of injection molding. There are many different kinds of polymer, allowing for a large variety of designs and applications across multiple industries. The process of injection molding is perfect for projects that require a large volume of products with complex features. Read more about Polymer Molding

Precision Injection Molding Basics

Precision injection is a method of injection molding that requires great accuracy. This type of injection molding is typically used to create smaller components that will be part of a larger assembly. The precise plastic parts are also often used to replace high-precision metal parts in instruments, electronics, optics, medical devices, and more. Plastic is an ideal replacement material as it is lightweight, readily available, and usually much cheaper than the original material. Precision molding is a sophisticated process that requires advanced injection molding knowledge. The experts at ICOMold by Fathom have decades of experience completing precision injection molding projects. Read more about Precision Injection Molding Basics

What is Prototype Plastic Molding?

Prototype plastic molding is a vital early step in the development of plastic injection molding components. Prototypes help identify design flaws and other issues during the design stage, saving the customer valuable time and money. Plastic prototype molds can be produced quickly and cheaply to stay within demanding deadlines and budgets. Prototype plastic molding can have the same functionality, shape, and fit as the final product minus specific details such as color or finish. Read more about Prototype Plastic Molding

What is PVC Injection Molding?

Polyvinyl Chloride (PVC) is a popular industrial thermoplastic used to create a variety of plastic goods including pipes, siding, automotive components, and more. PVC has excellent strength and weather resistance. Finding a knowledgeable manufacturer to guide you through PVC injection mold processing is important. The experts at ICOMold have the necessary experience to make your PVC injection molding project a success. Read more about PVC Injection Molding