Cable Overmolding — All You Need to Know

Cable Overmolding is now the most evolved form of wiring available. The Over-molding cable adds aesthetic value to the cables which the medical industry requires. While many haven’t thought of over-molded cables before, they are becoming more and more popular today. Do you want to know the reason? Then please come with me.

Chapter 1: What is Over-molding?

Over-molding is a new technology in the market. It makes wires have more longevity and reliability even in the harshest regions of the world. In this process, we combine the wire and the connector using two or more materials to make a single device.

It is a combination of the wire and the connector seamlessly combined. To do this, first, the cable assembly is put in a mold. You then cover the substrate – or the first material – with a molten plastic substance.

You inject the material using two techniques-

Insert Molding or single shot

Multiple shots or two-shot

So now you may think about why you should go for over-molded cables at all in the first place?

The answer is that these cables have more lifespan, and you can rely on them for durability and safety purposes. It increases the cable exit flexibility for better connections. Also, it offers better shock resistance on an enormous scale. Additionally, it creates water-resistant cables-all for your benefit!

In the next chapter, you will know more about which material to use for the over-molded cables.

Chapter 2: Overmolding Cable Material Selection

The first thing you need to know is that the major factor which choosing the material for your over-molded cables is Thermal Bonding. Thermal Bonding is the lock and key holding the over-molding material to the single cable and connector set. If the compatibility between your cable jacket and molding material gets skewed, then the entire assembly will not be a success. But do not fret! We are here to help you with just that. Just go through the table below for all the information you need to make an informed choice.

Common Overmold materials:
Name	Advantage	Disadvantage
Polyvinyl Chloride (PVC)	Great durabilityIt has great resistance to inclement weather, tension, fraying, and temperature.Can be both rigid or soft and flexible as needed	Regulation properties are not greatIt gets stiff in winters, sometimes
Polypropylene (PP)	Extremely resistant to even high impact, at a low costHas a good capacity for elongationIt does not react to acids and bases	It tends to break during wintersMaterial is not suited to extreme heat and UV rays.
Acrylonitrile Butadiene Styrene (ABS)	A wide range of industries use itVery tough at low costResistant to chemicals	This leads to extreme smoke generation when it burnsNot that resistant to inclement weather or solvents
Thermoplastic Polyurethane (TPU)	Resistant to frayingQuite elastic Best performer in the cold regionsHighly resistant to oil and all sorts of solvents	It is expensive compared to the other materials.
Thermoplastic Rubber	A mix of rubber and plasticSlip-resistantPerforms well in all weather conditionsGreat shock absorption	It tends to warp
Santoprene(TPV)	Easy to recycleConsistent in all weather conditionsGood flexibility	Poor chemical and heat resistanceHigh cost
Polypropylene (PP)	Does not react in contact with acidsHas a high tensile strengthIt is not prone to corrosion and chemical reactions	Very flammableIt has to be kept away from UV rays
Polyethylene(PE)	High flexibilityResistant to heatExtreme impact resistance	Cost is more than average

The next chapter will help you understand how to complete over-molding.

Chapter 3: The Process of Cable Overmolding

What is the process?

To satisfy your curiosity, let’s discuss it in brief and simple terms.

The process is simple and convenient. Here the cable and the connectors join together to form a single unit that is very easy to use. The process takes the help of bonding to make the unit. Here, a layer of plastic material, which is durable in origin, covers the original substrate through bonding. You can use materials according to your needs by following the informative chart above.

Over-molding achieves the best possible compatibility between the cable, the connector, and the over-molding material.

The two main techniques are injection molding and insert molding.

Injection molding:

It is an interesting and rather convenient process. The substrate is put in the mold and then molten plastic through injection shoots to create one solid unit. It is quite versatile and highly flexible, and is several industries use this technique.

Insert Molding:

When two parts connect, then we use insert molding. It is a permanent encasing of cable and connector. You normally see it in the cases of threaded inserts and electrical appliance encasing.

3.1: The process of Injection Molding:

The process is as follows:

Put the substrate in a mold.

Heat thermoplastic material.

We use high pressure to push the molten material through a nozzle into the mold.
Hydraulic pressure makes the material stay in its place.

Once we cool it, the single unit drops out soldered and perfect!

3.2: The process of Insert Molding:

The process is as follows:

Put the substrate in a mold.

We heat thermoplastic material.

The filling surrounds and fills up around the insert.

The completed product is a single unit.

The next chapter will introduce you to the application of these over-molded cables you are learning.

Chapter 4: The Applications of Cable Overmolding

The high usefulness of over-molded cables makes them very efficient and durable, and in sync with the latest technology.

The applications of over-molded cables are as follows:

1. Cable Overmolding–Military Market Applications:

 Military components now use over-molding for longevity and more effectiveness and durability. So, you can upgrade these instead of replacing them.

2. Cable Overmolding–Medical Market Applications: 

You use these in surgical instruments for better gripping. Plus, it’s been seen that the instruments can withstand autoclaving and acidic and basic harsh cleansers.

3. Consumer electronics: 

You find these everywhere including in laptop chargers, or cords for the television. If you need durability, convenience, and grip, you need these cables.

4. Solar energy:

 They are heat resistant, and you can easily use them in transmitting solar energy through cables.

5. Industrial/OEM:

 Medical OEMs use injection molding to get the best results. It reduces cost, is patient friendly, and you can use them to create custom designs.
Let’s learn next about the benefits you get when you use over-molded cables.

Chapter 5: Benefits of Cable Overmolding:

So why use over-molded cables over the simple ones for your cable assembly? What is so different about them that makes them special and much better?

The following are the benefits of over-molded cables:

Boot IP rating: Gets increased

Provides the product design freedom: We see that these are easier to work with as they are flexible and not brittle. So, we can easily mold them to form malleable cables. As they have flexible exits, the movement is easier.

Improves the aesthetic appeal of cabling: These are easier to dye. You can find several colors. These are useful in the medical industry for aesthetics and helps in improving the doctor-staff-patient relationship.

Simplifies installation and Decreases human error: There is only one single unit of cable and connector bonded together using thermoplastic material. So, it is easier to install, and you reduce the human error to a minimum.

Enhanced the Durability: Over-molded wires offer durability or longevity so that the wires do not get abrasions. You don’t have to worry about safety issues in the long run, even in the harshest of environments.

Increasing product quality and durability: The product quality is better than individually using the cables and connectors. Plus, these cables have more lifespan. You can rely on them for durability and safety. Increase the cable exit flexibility for better connections, get shocked resistance of enormous scale, and create water-resistant cables-all for your benefit!

You will learn about the difference between over-molding and two shot molding next.

Chapter 6: Cable Overmolding VS Two Shot Molding

There is a slight difference between the two. You are now going to learn about the difference between these two and which one you will need.

Over-molding is a new technology in the market. It makes wires have more longevity and reliability even in the harshest regions of the world.

The process is simple and convenient. Here the cable and the connectors join together to form a single unit that is very easy to use. The process takes help of bonding to make the unit where a layer of plastic material which is durable in origin covers the original substrate through bonding. You can use materials according to your needs by following the informative chart above.

The main success of Over-molding lies in achieving the best possible compatibility between the cable, the connector, and the over-molding material.

Two shot molding:

This process is the best for bulk orders, and factories use this process for large production volume of more than 10,000 parts. Usually, the products that have colors and materials and components of multiple nature use this process.
The process is simple. It is the same as injection molding.

The process is as follows:

Put the substrate in a mold.

We heat thermoplastic material.

We use high pressure to push the molten material through a nozzle into the mold.
The difference lies in the fact that it involves more than one nozzle — the process changes by injecting a single mold with multiple materials – in only one molding cycle.

There is a steel layer that creates space for one material after you inject another.

Where Over-molding costs you fewer labor charges, multiple molding has more. However, the unit cost is much lower, and the enhanced designs have greater reliability than in over-molding. In over-molding, essential and individual parts get more attention.

So which is better? The multi-cavity or the single cavity molding?

Let’s learn about this now.

Chapter 7: Cable Overmolding—Multi Cavity VS Single Cavity

The difference is as follows:

Multi-cavity	Single-cavity
This mold is useful in large scale productions, generally in industries.	This mold is for a single small production
Cost is greater in the beginning, but each over-molded part costs less	2. The cost of each over-molded part is more than in the case of multi-cavity.
Requires less machine time	3.Requires more machine time
2-20 cavities present	4. Generally, eight cavities are present

The Advantages and Disadvantages:

The main advantages of multi-cavity molding are that it is very efficient and cost effective for bulk production in factories. It makes the production of individual over-molded parts easier and cheaper. The disadvantage is that in case the product needed is not in bulk, for that the setup cost up front is very high. If one mold breaks, you have to change the entire machine, which signifies the serious loss of money.

For the per piece over-molded part, the single-cavity is much better.

Conclusion:

Using over-molded cables reduces the costs of making a product. You can use it efficiently and with durability. You should work with teams that make the task easier, less time consuming, and lets you create unique and new designs.

Contact us today, if you’ve cabling needs for

Equipment exposed to the harshest weather conditions,

Medical equipment that needs utility as well as aesthetic qualities

The Cloom teach team is always ready to answer any questions you might have. Talk to one of our experts to know how we can help you with your cabling needs.