Insert Molding VS Overmolding: Differences And Comparison

Insert Molding VS Overmolding Differences And Comparison

There are two ways to make things using plastic: insert molding vs overmolding. They are often used to make things that are sold to businesses and other companies. Both things are similar because they cover one part of plastic with another part.

Both have different jobs as they have different roles and do different tasks. If you don’t use the two forms correctly, it can lead to many bad things happening.

Sometimes things don’t work, and it can be frustrating when you’ve already spent a lot of time and money on them. It can also be a problem if making something costs too much.

This article helps you decide which is better for your project Insert molding or overmolding.

Further, we will compare two ways of making things, called Insert molding and over-molding, in this article. We will examine the similarities and differences between them.

What is Insert Molding?

Insert molding is a manufacturing process where plastic is molded over a metal part called “Inserts. The method is similar to regular injection molding but with an added tool. This means putting something inside a container and then filling it with a liquid plastic to make a solid shape.

So, the thing that’s stuck inside becomes known as plastic material. After some time, getting thrown out occurs.

What Is Insert Molding

There are two ways to do Insert molding: by hand or by machine. One way to control things is by using a manual handle. It is cheaper and easier to use for the person in charge.

However, the programmed handle makes sure that things can be done the same way every time, errors are reduced, and things are made more efficiently.

Pros of Insert Molding

Insertding molding has many uses because it has many advantages. Here are some reasons why you should think about using this method for your project.

  • Insert molding is a good way to create strong and long-lasting connections.
  • It saves money.
  • Insert molding can make utilize of a wide run of different plastic gums. These counting thermoplastics, Nylon,  which is eco-accommodating since you’ll reuse them. All of these are light and solid, making them suitable for everything from shopper products to heavy-duty mechanical ones. Elastomers and thermosets like epoxy are two other common materials. Normal flexibility, which is major zones of quality for both versatile, could be a veritable outline of the final alternative.
  • This means that the material is suitable for creating cases that are thin and cannot be tapped into easily.
  • Inserting molding gets freed a moment step within the fabricating handle called to get together. There’s no require for a partitioned errand since the addition of metal or other components is a portion of the molding step. Time and cash went through on labor and specialized hardware for these forms are spared as a result.
  • The need for parties is decreasing.
  • Improves how well the plastic and metal parts work together, making the product work better.
  • Parts made of plastic can be up to 50% lighter than those made of metal. One of the essential reasons that businesses are turning to plastic molding for parts is since of this and its quality. Lighter weight moves forward execution and usefulness in an assortment of ways; counting moved forward surgical instrument client invitingness and fuel effectiveness.
  • Furthermore, the fabricating strategies for molding themselves are temperate.  Not at all like diverse sorts of adornment, get together and work expenses can be smoothed out.
  • Good for keeping things strong, preventing shaking, wetness, and dirt.
  • Insert arrangement exactness in a shaping plan cannot be accomplished utilizing other molding forms. In a nutshell, coordinates plastic parts are altogether tougher and more reliable. Moreover, since this one-step method does not include gathering, fabricating presents fewer openings for mistakes

Cons of Insert Molding

  • Using Insert molding is a good choice for some things. It’s not fair for others. Use these. Here are a few problems with the method.
  • Resin can shrink and get stuck in the object it surrounds, causing problems.
  • Making complicated parts needs a lot of special skills.
  • This needs different ways to produce things, like metal and plastic.

Consideration in Insert Molding

When you create things with a shape, it’s important to think about how the shape looks. It’s important to plan the shape correctly to protect the things inside from getting damaged by extreme temperatures or heavyweight.

There are a lot of things to think about when including something.

Consideration in Insert Molding

  • Make sure to keep the object in the same place when creating the shape. If it moves, it will break completely. It’s really important to have the plan to keep things organized.
  • You need strong and stable features to ensure the inside of your shaped parts stay together.
  • Use trustworthy companies: Because the person or company you work with to create forms is very important in determining how good the work will be. It’s very important to use companies like Kemal that guide you on new ideas and materials needed to make something whole.

Applications of Insert Molding



This molding process you use for aviation purposes. The aviation business uses a way of making things called “Insert modeling.” They use it to make airplane seats, locks for places to store things, toilets, handles and switches that people can touch.


Car molding is when a strip of material is attached to the body of a car to make it look nicer and provide protection. Car companies also use a lot of molded parts. In this field, using a mold to make plastic parts makes them stronger than metal parts.

Also, this change happens when making lighter car parts. This helps improve how much fuel the car uses. This means that it saves money on labor and expenses while making designs more reliable and flexible.

Medical Devices

Medical stitches

The health department will also benefit a lot from this approach. The technique can make healing tools that range from simple to very complicated and delicate ones, like stitches and screws. Using injection molding can help create many medical electronic devices.

There are many things that prosthetics, objects to help with therapy, sharp tools for surgery, and rooms used for medical treatment can be used for.

Further, some medical tools can help you feel better even if you’re not following all the usual rules, like tube valves and needle points.

Other uses include…

  • In-mold labeling, or IML, is when a printed film is put inside something while it is being made. So, IMD is when a printed film is put inside something to make it shiny. A special plastic is added to the film, which makes it shiny and strong.
  • Bushings, studs, and tubes have certain characteristics or features that make them easily identifiable or unique.
  • The handles are used to control machines, gather things and control them.
  • “Strung latches” means latches that are pulled tightly or latched securely.
  • Common electronic parts and machines.

What is Overmolding?

Overmolding is when a layer of plastic, usually a soft kind, is molded on top of something that’s already been made. TPE is often used in this process. It’s a commonly

used material for the outer layer. The handle can be made from any material, including plastic

and metal. Think of it like putting a cover on something made of hard plastic to combine different materials into one piece.

To make overmolding work, the outside layer must stick to the material beneath it through a chemical reaction. The two things need to match to make it work, so the thing underneath is usually some plastic material.

If the cover material and the surface it goes on don’t match, they won’t stick together very well. Someone can fix this by putting mechanical keys into the material below it, all the way from the top surface to any holes or weak spots.

To make something of the best quality, engineers use both chemicals and machines to design and hold it together. It works in two ways.

Manual Molding

With a manual operation, the substrate is insert molded by means of a conventional insert molding handle. The substrates are, at that point, hand-loaded into another form for the overmolding operation.

The administrator will moreover expel the wrapped-up portion from the form, give a review, and bundle the parts. Manual overmolding is the foremost common method for moo to mid-volume overmolding.

The advantage of manual overmolding is effortlessness. The tooling required for the substrate and overmold is straightforward (when compared to two-shot tooling), and there’s no auxiliary hardware required.

The drawback is the labor allotment and the potential for conflicting cycle times made by administrators. As yearly arranged volumes increment, the labor included can end up critically sufficient to legitimize venture in robotization frameworks or a two-shot molding operation.

Two-Shot Molding

More progressed insert molding machines can run two diverse polymers at the same time. Two-shot molding is a complex process where a machine is used to shape the material on one side and then switch to shape the other side.

This happens on each cycle. The method requires a more progressed insert molding machine and form, but it may surrender a lower piece cost compared to manual operations.

Choosing between the two molding operations is done on a case-by-case premise. There’s no universal run of the show as to when an automated overmolding operation is defended.

To supply the end-user with the most excellent alternative, insert molders will see a few factors, such as labor allotment, yearly arranged amounts, budget, fabric utilization, cycle time, etc.

Here are a few things to consider:

  • Beware of thin edges: Edges that taper to a fine point should be avoided. During Insert, easing back of the stream and resulting cooling can antagonistically affect the attachment between the substrate and over-molding.
  • Overmolding thickness should remain uniform: If you need sections of varying thicknesses, smooth out surfaces as much as possible and avoid abrupt changes in thickness. The over-molding should maintain a constant thickness between 1.5 mm and 3 mm (0.060 – 0.120″).
  • You can use smooth bumpoffs in the design because many over-molding materials are flexible.
  • Keep the over-molding layer thinner than the underlying substrate to help prevent warping.
  • To guarantee proper fixation in the over-molding cavity, take into consideration the substrate’s shrinkage.
  • Choosing the right materials is another important thing to think about when designing. The substrate typically consists of a harder plastic or a combination of plastics to achieve the desired properties.

Advantages of Overmolding?

Advantages of Overmolding

The handle made with overmolding insert molding is very useful and can be used in a lot of different industries and businesses. It’s very similar to the process of Insert molding.

Overmolded parts are useful in the following ways:

  • Things you can hold easily, like plastic handles.
  •  Overmolding process, the product’s execution will improve. This includes an electrical separator, chemical resistance, and item execution for reducing stun and vibration.
  • Things used in a place that shakes a lot get really hot and have electric shocks.
  • To make things taste better, we add colors that either go well together or look different from each other.
  • Things that have designs or patterns, which have a logo or name of a company on them.

What Are the Disadvantages of Overmolding

Overmolding has many good points, but before choosing it, you also need to consider some bad points.

Multi-Step Process

Making over-molded components needs two steps. Using over-molding takes more time and makes each item cost more money than making just one item without over-molding.

cost increase

It means you need to use two tools or a complicated process to make something, which costs more money at the start. Overmolding is a good idea when the only other option is to make two separate pieces and then put them together.


When different materials are mixed together in a machine to make something, there is a chance they might separate and come apart. This often happens when the temperature is too hot or too cold for the materials used.

Sometimes, when we need to join materials together, we can’t just use heat to stick them together. In those cases, we might need to use mechanical interlocks to hold the materials in place. Other cons include.

  • It needs different ways to shape the material, making it take longer and costing more money.
  • More machines are needed than just one for injection molding because of the two-step handle that helps to increase the quality obtained.
  • Delamination can occur when the temperature fluctuates within its appropriate range.
  • Sometimes, special tools are needed, which can increase the cost of making something because the people making it may still need those tools and have to buy or rent them.
  • Not all types of plastic work well together. So, working with your plastic molding service provider is important to get the best materials.

Applications of Overmolding

The handle made with overmolding insert molding can be used in many different types of businesses. It’s similar to Insert molding.

Overmolded parts are useful in the following ways:

  • Things you can hold easily, like handles made of plastic.
  • The things used in a place where there is a lot of shaking, heat, and electric shock.
  • We use different colors to create items that look really good.
  • Things that have special designs or shapes that show a name or symbol of a business or group.

Differences Between Insert Molding VS. Overmolding

Both forms are similar. There are many differences between options, and you should pay attention before choosing the right one for your project.

The difference between overmolding and Insert molding is about the following:

Process Differences

Process Differences

The big difference between Insert molding and overmolding is how it’s made. Overmolding is a way of making things by putting one layer of plastic on top of another layer of plastic. It is called two-shot molding because it happens in two steps.

First, one layer of plastic is molded, and then another layer of plastic is molded on top. Insert molding is when plastic is put on top of something that is not plastic. This process is different from overmolding because it only requires one step to make the handle. The inner part is made separately.

Cost Differences

Overmolding can be expensive because it requires two different ways of putting the material in the mold. In addition, using Insertded molding reduces the cost of production and improves efficiency, especially for large-scale manufacturing.

However, they are more expensive than injection molding.

Material Selection Differences

Material Selection Differences

From one viewpoint, overmolded parts come from plastic parts that can shape synthetic bonds with one another. However, not all plastic materials are compatible with one another. For delineation, ABS is compatible with ABS, Polycarbonate, and Polyethylene, yet not with POM.

However, most plastic materials are compatible with non-plastic components. Insert molding is, therefore, more compatible with fabrics.

Keynote: Before choosing a plan, make sure you are familiar with a variety of insert molding materials. In addition, you should seek the advice of an insert molding service provider regarding the appropriate material to select.

Production Speed Selection

Both things need time. Insert molding takes longer because it involves adding another layer to the item, which is the Insert itself. In simpler words: In overmolding insert molding, the handle is divided into parts.

Insert molding is different from overmolding because you don’t have to make two plastic parts separately. With overmolding, you have to make the main part and then add an extra layer on top.

Common Application of Insert Molding VS. Overmolding

Overmolding and Insert molding can be used in a variety of industries and product types without restriction. Since the two techniques are so important and adaptable, present-day practical applications are being made all the opportunity that makes the most of their advantages.

There are numerous examples:

electrical switches

Hand and control tools, equipment for growing and harvesting, kitchen utensils, clothing, electrical switches, health and beauty products, household appliances, vehicles, furniture, computers, gadgets, toys, activities for therapeutic disobedience, and much more.

How to Choose Between Insert Molding VS. Overmolding for Your Project

The type of preparation that suits you depends on what you need it for. Make sure you know that these techniques aren’t usually only used by important purposes because they have different reasons for using them.

Actually, it’s not unusual to find both used on one thing. Imagine a device that has grips attached to the handle and is also held together using nuts.

Use Insert Molding When

Use Insert Molding When

You should think about using Insertding molding because it has some important benefits. One thing to remember is that your product may need strong parts to hold it together, usually to enclose it or protect it.

Nutserts that are strung are really good for this. However, there are also many types of snap connectors available.

Insert molding is a process that puts a handle made of rubber or plastic on a metal tool or knife used in households.

Insert molding is great for putting wires and electrical connectors securely into plastic containers that protect them from moisture and dirt.

Use Inserts when you need to open and close a plastic box repeatedly, like when doing regular maintenance or replacing batteries.

They got a little extra, but it came at a cost that is offset by creating a stronger final product.

Use Overmolding When

Use Overmolding When

Product designers should think about overmolding to make parts that are easier to hold and have a smoother surface. This can also help protect the user from things like vibration, heat, or electricity.

Overmolding is a good way to attach the rubber to metal permanently, such as on wheels and casters.

Overmolding is a process that allows us to be creative by adding colors and designs to make the part look better and work better.

Overmolding adds cushion and shock protection to many everyday household items to help protect customers from accidental harm.

Why Choose Kemal for Insert Molding VS. Overmolding Services

Why Choose Kemal for Insert Molding VS. Overmolding Services

Prototypes and finished goods can be made cheaply using this method. We have a lot of skills so that Kemal can make many different things for many different industries really well. Our technical team is extremely knowledgeable and skilled.

They can guarantee the success of your project at a low cost. We have made our overmolding and Insert molding services easy to request in Kemal. So, if you don’t have much money, you can still use our website to create citations quickly.

Do you need help making your parts with Insert molding? If you’re not sure, contact Kemal. Their skilled engineers can help you. As we always pay attention to little things to ensure our parts satisfy our customers. A lot of our customers agree with this.

What are you waiting for?


Insert molding is a method for making inexpensive items that are simple to modify. Insert molding and over-molding are two smaller processes used to make parts. Many of the things we use every day are made using this method.

People typically have to choose between Insert molding, over-molding, or just sticking with regular injection molding when deciding how to make a product using injection molding. It is essential to clearly define the product’s intended use when evaluating the benefits of a process.

Depending on which kind of product they work best with, each method is used differently. Conversing with specialists right off the bat can assist you with sorting out the ideal way to make your item.

Put your parts into production today

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