PCB Overmold | Revolutionizing PCB Protection


PCB overmold is a cutting-edge technique that has recently rocked the industry. Several PCB manufacturers across the globe use this approach. As the PCB market grows around the world, PCB overmolding grows at the same rate.

In 2021, the size of the global PCB market was over USD 75 billion, and between 2022 and 2030, it is anticipated to expand at a compound annual growth rate of over 5%.

Electronics are getting smaller and more complicated, so safety measures like overmolding are becoming more and more important. Overmolding improves device durability and dependability, and manufacturers across sectors are using it.

With the growing popularity of the IoT sector, which demands tiny, robust, and dependable electronic devices, PCB overmolding is predicted to increase. With the need for smart devices, sensors, and other Internet of Things (IoT)-related products on the rise, overmolded PCBs are likely to be in high demand.

Materials and technological advances have made PCB overmolding cheaper and more efficient, boosting its market share. PCBMay stays ahead of these advances to provide our customers with the best PCB overmolding solutions.

There is a lot more to tell you about PCB overmold. So without further ado, let’s dive in.

What Is PCB Overmold?

It refers to the practice of covering a PCB with a protective coating, often a polymer resin. This shields from elements, including humidity, dirt, and thermal gradients. Common uses for overmolded PCBs include the manufacturing of automobiles and technological devices.

With PCB overmold, a polymer resin is injected over the PCB and allowed to cure all around circuitry, forming a tight and secure sealing. This may be accomplished in several ways, including two-shot molding, insert molding, and transfer molding.

Overmolding techniques may range from simple to complex, depending on the application’s requirements. Whether or not an overmolding job is successful depends on the polymer resin utilized.

PCB overmold increases the circuit board’s longevity and dependability. Mechanical pressures and impacts may cause PCB failure, although being overmolded help prevent it. Overmolding may also increase the PCB’s electrical insulation, making it less likely to short out.

PCB overmold allows personalization by matching polymer resin color and texture to application needs. This is especially helpful in aesthetically-driven fields like consumer devices, where the user experience is just as crucial as the product’s visuals.

Can You Customize PCB Overmold?

You can modify PCB overmold to meet the needs of your application. For further protection, a PCB might undergo a procedure called overmolding, in which a polymer resin is used.

Often, modification entails changing the resin’s color, surface roughness, and other qualities to better suit a certain use case.

Having PCB overmold made to order allows you to better meet your product’s visual needs. The aesthetic value of a consumer electronics device is often as essential as its practical use.

Adjusting the resin’s color and surface texture may make the result appear precisely as you prefer. If you want your goods to stand apart in a saturated market, you may also have the resin explicitly made for you.

The selection of resin substance is also crucial when modifying PCB overmold. Choosing the appropriate resin based on its qualities is essential for the best product performance in its intended setting.

For instance, if your goods are used at extreme temperatures or with strong chemicals, you’ll require a resin that can withstand such conditions.

Resin characteristics can be changed to improve the product’s strength and dependability. For instance, mixing in fillers or reinforcing fibers may make resin more durable and resistant to impact and abrasion.

Furthermore, adjusting the resin’s electrical characteristics to your specifications will assist in shielding your goods from ESD and other potential electrical gremlins.

Customized PCB Overmold

Customized PCB Overmold

What Material Is Used for PCB Overmold?

PCB overmolding undoubtedly keeps your PCB safe. So, you might ask, what materials are used to make the overmold.

PCB overmolding uses rubbers and thermoset polymers. PCB overmolding material relies on the electronic device’s needs, such as protection, environment, and final product qualities.

Most of the time, thermoset plastics like polyurethane, epoxy, and silicone are used to overmold PCBs. These materials last a long time, are resistant to chemicals and heat and can be changed to meet specific needs.

PCB overmold material

PCB overmold material

Polyurethane, which is impact-resistant and heat-resistant, is a common overmolding material.

PCB overmolding is also often done with rubbers like silicone and neoprene. These materials are very flexible, can withstand high temperatures, and are good at insulating electricity.

Silicone is often used for overmolding because it has a high tear strength, is resistant to chemicals, and can keep its shape over a wide range of temperatures.

What Is the Minimum PCB Overmold Thickness?

The overmold material, PCB size, and protection level determine the minimal PCB overmold thickness. In most cases, the minimum thickness of the overmold should be enough to protect the PCB and its parts.

To optimize molding cycle duration, substrate, and overmold wall thickness should be consistent. Most overmolding applications will work well if the wall thickness is between 0.060″ and 0.120″ (1.5 mm and 3 mm).

The electrical device’s size and weight might be affected by overmold thickness. Hence, the minimal overmold thickness should balance protection with gadget size and weight.

PCB overmold thickness

PCB overmold thickness

What Are Some Common Design Considerations When Implementing PCB Overmold?

PCB over mode is one of the most important things for manufacturers to think about these days. Thus, PCB overmold design requires caution. If you don’t follow the right instructions, you could mess up the end result.

  1. First, there is a strong shear dependence on the viscosity of GLS overmolding TPEs. To guarantee the optimum flow of the TPE material, the mold design and the molding process parameters must be carefully tuned.
  2. The position of the injection gates is another key factor when building molds for overmolding PCBs. Gates should be installed at the thickest TPE wall section to guarantee good flow and reduce voids and other flaws in the completed product.

To guarantee appropriate component ejection from the tool, carefully constructing the mold is also crucial. This may reduce blemishes on the elastomer’s soft surface and guarantee a high-quality final result.

Cooling properly reduces cycle time and ensures quality.

  1. Finally, when making molds for overmolding, it’s important to consider flow ratios. Most overmolding applications should not exceed 150:1L/T flow ratios. This ensures that the TPE material fills the mold without flaws.

PCB overmold design

PCB overmold design

How to Find a Reliable and Experienced PCB Overmolding Supplier?

Locating a trustworthy and experienced PCB overmolding manufacturer can be difficult. There are a lot of things to think about, like price, quality, delivery schedule, customer support, and technical support.

If you rush through this step, it could cost you a lot of money and cause your business to fail.

PCB overmold manufacturer

PCB overmold manufacturer

Check out the company’s reputation

Do some research online or ask people you know for recommendations. Search online for “PCB overmolding provider,” “PCB encapsulation service,” or “low-pressure injection molding manufacturer” to find vendors.

Check their web pages, reviews, testimonies, and certifications to learn more about them.

Ask for a price quote and some samples

Send out quotation requests to multiple vendors. Compare pricing, lead times, minimum orders, payment conditions, and delivery choices.

You should also ask for examples of their past work and, if possible, visit their facilities. During this process, you should judge their ability to communicate, how quickly they answer, and how professional they are.

Experience and expertise

PCB overmolding is a specialized process that requires a high level of expertise. You should choose a provider that can provide what you need.

Choose a manufacturer that has experience overmolding electrical devices like yours. Ensure they are competent to optimize your PCB design for overmolding and use the proper materials and procedures.

What Is the Difference Between a PCB Insert and Overmold?

Overmolding and insert molding reduce extra assembly stages, generate multi-material items without adhesives, and enhance the final product.

Keep in mind that PCB insert is not the same as you would think of overmolding. Let’s shed light on the difference they have:

Operation Speed

Insert molding only takes one shot, while overmolding takes more than one. This means you can get more batches ready by using PCB insert in the same amount of time as you would by overmolding.

But look out for some exceptions. Sometimes the fastest way is not always the best way. In certain situations, manufacturers may need to produce unique metal inserts, which might delay manufacturing.


PCB insert uses one shot of injection which is easier than its counterpart, the overmold, which uses two shots. But this more straightforward operation has one drawback. You have to make or buy the metal insert separately.


Both operations are fast, and they can secure your PCB well. But what varies is the price of these two operations.

As you may have guessed already, insert molding costs less than overmolding—the two shots of overmolding cost more.

If you are looking to save money, PCB insert will be your best friend.

Design flexibility

PCB inserts are usually easier to design because they are easy to swap out or change to fit changes to the PCB. Overmolds are harder to change or replace, and some changes may require the overmold to be redesigned from scratch.

Assembly simplicity

Most of the time, PCB inserts are easier to assemble than overmolds because they require fewer steps and can be fastened with screws or clips. Overmolds’ complicated manufacturing process may raise installation time and cost.


Can PCB Overmold Affect the Durability and Lifespan of a Product?

Yes, PCB overmolding can have a big effect on how long and how well a product lasts. When designed and used correctly, This technique can give an electronic device’s PCB and other sensitive parts high protection and resistance to impacts.

This can help stop damage and failures caused by moisture, debris, vibration, and other external conditions. As an added bonus to its protective function, PCB overmold may also increase the mechanical stability of electrical equipment.

The overmold material can help absorb and spread out shocks and vibrations, making it less likely that the PCB or other parts will get damaged while in use or in transit.

What Are the Benefits of PCB Overmold


Elevate your IP rating

During the overmolding process, a material bond is made around the PCBs, wires/cables, and connectors. This creates a watertight seal that keeps dirt, dust, and other debris from getting into the electrical components.

Increase Strain Relief

Traditional protections like heat shrink, potting, and backshell connectors don’t last as long as overmolded links.

Protect From Shock and Vibration

The overmolding process fills in any spaces around internal parts, so no air gaps would allow parts to move. Because of this, overmolding is the best way to keep damage and wear from happening.

Upgrade Lower-cost Components

Overmolding makes a strong and weatherproof seal around electrical components. This means you can use cheaper parts to build a better electrical assembly.

Enhanced Aesthetics

Overmolds can be made in different colors and finishes, making an electronic device look better and more appealing to consumers.

How Does PCB Overmolding Comply With RoHS Regulations?

Use RoHS-compliant materials for PCB overmolding. The use of heavy metals such as mercury, lead, cadmium, and hexavalent chromium is strictly prohibited.

There are a lot of RoHS-compliant materials for PCB overmolding, such as TPE and TPU. All electrical components may be safely assembled using these materials since they contain no banned compounds.

PCB overmolding manufacturers must have the necessary paperwork and testing methods in place in addition to employing RoHS-compliant components. This means keeping track of the materials used and testing them regularly to make sure they are right.

What Are Some of the Uses of PCB Overmold?

PCB overmold provides so many advantages to PCB and overall electronic devices. PCB Overmoold has expanded in several industry areas. Among them, some are-

  1. To shield circuit boards from heat, moisture, and vibration, PCB overmold is often used in automobile electronics.
  2. Smartphones, tablets, and wearables employ overmolded PCBs for impact and environmental protection.
  3. PCB overmold can be used in medical devices to keep them from getting dirty and to make them last longer.
  4. Overmolded PCBs may shield sensors, switches, and controllers from environmental damage and increase device longevity.
  5. PCB overmold is often used in aerospace and defense to protect against high heat, radiation, and pressure, among other things.

PCB overmold in automobile

PCB overmold in automobile

How to Determine Which Materials Are the Best for PCB Overmolding?

Almost any combination of available materials may provide a wide range of distinct outcomes. You can change the overmold stiffness and strength by combining any amount of chemicals.

 PCB overmold quality check

 PCB overmold quality check

Selecting the appropriate material for PCB overmolding is based on a number of criteria.

  • Determine the application criteria.
  • Consider the surroundings.
  • Find out the quality of the material.
  • Pick a material that fits your needs.
  • Carry out tests

PVC, as well as TPU are two of the most common materials for overmolding. The first one is common because it is cheap and good at keeping out water and making things stronger.

What Are Some of the Challenges PCB Overmold?

PCB overmolding may increase electrical device longevity, environmental protection, and personalization. But the overmolding process also has some problems that can affect the quality and reliability of the final product.

Here are some common problems that come up with PCB overmolding:

Things like the environment, the needs of the application, and the properties of the material.

Precautions to Take in the Design: For the overmolding process to work, the mold must be designed well. To make sure the final product meets the requirements, items like gate location, cooling, and component ejection must be carefully thought out.

Controlling the process: The overmolding process needs careful monitoring of the temperature, pressure, and timing to make sure the material cures correctly and sticks to the substrate. Changes to these process parameters can cause defects like voids, sink marks, and warping.

Cost: PCB overmolding can be more expensive than other ways to protect or encase the PCB. It uses more materials and has more steps in the manufacturing process.

How to Ensure the Quality of PCB Overmold?

PCB overmold quality is crucial to the manufacturing process’s success and the final product’s reliability. Here are some tips to help make sure that PCB overmold is of good quality:

1. The PCBA and its parts’ design

The PCBA should be homogeneous in thickness and free of sharp edges or corners that can concentrate tension or trap air during molding. The components should be low profile and tightly fastened to the board to minimize the difference in molded section thickness. The PCBA should also have enough holes or channels for air to escape while it is being molded.

2. Material Selection for Plastic

For overmolding, the plastic should stick well, expand when heated, keep electricity from getting through, and be resistant to chemicals. The plastic material should also match the PCBA’s thermal profile so that it doesn’t bend or break because of heat stress.

Before overmolding, the plastic component should be checked for compatibility with the PCBA.

3. Mold design

A successful overmolding procedure depends on a well-designed mold. The mold should be made so that the overmold material fills the mold cavity evenly and completely, with no voids or sink marks.

Moreover, the finished product should be properly cooled and ejected from the mold.

4. Process control

The overmolding process should be carefully managed to make sure that the material cures properly and sticks to the base. To do this, you must regulate the injection and curing processes’ temperature, pressure, and timing.

During the overmolding process, problems can be found if the finished product is carefully watched and inspected.

5. Validation and testing

It is important to test and validate the overmolded product to make sure it meets the performance requirements. According to the application, it might involve testing the mechanical, environment, and electrical parts.

6. Supplier selection

To guarantee a high-quality end result, it’s important to work with a reliable overmolding provider.


PCB overmold is becoming a more popular way to improve electronic products’ durability, reliability, and functionality. Manufacturers can enhance the mechanical characteristics of PCBs by covering them with a protective coating of overmold material.

Notwithstanding its drawbacks, overmolding is a desirable solution for many applications due to its advantages. PCB overmolded products can achieve high levels of quality, efficiency, and customer experience with the appropriate material, provider, and process control.

PCBMay is a great option if you need PCB overmolding from a reliable company with much experience. Our expert team can help you determine the best substances and procedures for your application. This will make sure that the quality and performance are at a high level.

At PCBMay, we’re committed to giving our customers great service and help throughout the entire process, from design to delivery. We have reasonable prices, quick turnaround times, and a variety of options to meet your needs.

Visit our website, call our team for a quote, or learn more about our PCB overmolding services. With our high-quality PCB overmold solutions, we’re excited to work with you and help you take your electronic products to the next level.

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