Curly cord: An Ultimate Guide on Curly Cables

When your phone is ringing, you grab it off its stand and drag it towards you. Here, curly cords ensure that the wire does not bounce right back after you go to the end of the line. And the handset’s coiling cords neatly retract into the base when it’s put back. The cable’s expansion is due to the presence of coiled conductors. Without it, you’d have a huge mess of wires behind your telephone. So, how important is the curly cord?

Curly Cords Basics

You can get a curly cord everywhere, from a car charger for your phone to a cheap key chain at the corner store. One widespread application is the telephone, which uses curly cords to connect the handset to the base unit. “Curly cords” connect two devices when one or both need to move relative to the other.

Besides their more common names, curly cords can also be referred to as:

• Coiled Cable
• Coiled Cord
• Spiral Cable
• Retractable Cable
• Coil Cable Retractile
• Retractile cord
• coil cords

These power cords get their names because they go back into a tight coil. 

Caption: Wire around a plier

Two Basic Categories of Curly Cords

There are two kinds of curly cables, mainly cycled and stationery.

Cycled curly cords

The first group, or cycled one is for medical devices. It is because you have to use them many times and can’t fail at all; hence, they are built differently. So, the process for making stationary curly cords is very different from the process for making reliable curly cords.

Stationery curly cords

As for the stationary one, these curly cords can stretch only once. It means you can use them when one of your devices is in a fixed position while the other keeps moving away. Moreover, you cannot go back and forth with stationary cords. Instead, you will always use them to connect a stationary and a moving device. These kinds of coiled cords would be made for a purpose that keeps them mostly still.

Caption: Silver gray curly cords

Spiral cables penetrate many industries.

You can find the curly cords just about anywhere. 

Medical setting

As mentioned above, medical devices need curly cords for convenience.

Electronics industry

The two most popular locations are the house and the car. For example, the convenience of your phones would not be there if spiral cables were not present. So is the phone car charger.

Telecommunications business

Spiral cables join cell phone connectors and the cigarette lighter adaptor plugs that power them in cars. Also, you will look for everything from GPS to radar detectors and cooling systems that you attach to a car’s cigarette adaptor.

Retails

Additionally, curly cords prevent the theft of high-priced merchandise from store displays. It tethers the products so that customers may drag them only a short distance before the wire snaps. Hence, the retail sector joins the ranks of those that place a premium on spiral cables, such as the cellular phone sector, the public safety sector, the medical sector, and the GPS/radar detection sectors.

Automobile industry

You may have seen the curly cord in every car production plant that employs robotics and power tools.

Building industry

On the highway, if you come across a construction site, you’ll likely find spiral wires linking GPS units to tiny computers on the machinery used to move or pave the earth. They communicate the data such as elevation data, dirt and concrete volume, and other construction site metrics. Moreover, it allows you to observe the procedure from afar. Thus, curly cords with many turns enable this entire system. 

The benefits of the Curly Cord

• Mobility – As mentioned in the phone example above, spiral cables can be readily bent and moved to access areas that normal wires can’t. Hence, more freedom at work through mobility equals more output.
• Durability – Spiral cables are often thicker than ordinary cables, making them more resistant to durability. Because of their thickness, they sustain little harm when gliding over uneven ground.
• Compatibility – Standard cables take up more room in storage than their spiral counterparts. However, curly cords don’t take up as much room as other wires because of how easily they coil up.

There are some benefits and cons to using spiral cables. Though they are lighter than standard cables and can help you save space, they are heavier. The cable might cause injury to nearby objects or people if you stretch it too far and then retract it improperly.

Caption: Spiral electrical wire at the construction site

Specifications of Curly Cords

The following is what must be taken into account when you are choosing a curly cord.

Cores and Conductor size

Spiral Cables are available from 2 to 25 cores with conductor sizes as little as 0.14mm2 up to 6mm2.

Screen

To accommodate the spiral’s expansion, you will use a lapped screen. In such cases, foiled screens are not a good choice.

Material and Color

• PVC is inexpensive to produce but has a poor memory; it recoils back after some uses. The range of available colors in these is typically greater. PVC cables have a 3.5x length-to-size ratio when extended.
• PUR is highly flexible and has excellent memory. Moreover, it resists most oils. If it were black, it would also be UV stable and resistant to the effects of water. Though typically black, you can also find them in white, yellow, and orange. PUR cables have a 4-to-1 stretch-to-retract ratio, making them extremely versatile.
• Rubber is useful in manufacturing settings. Comparatively speaking, it has a greater memory than PVC but is not as good as PUR. It would be impervious to moisture and sunlight. Rubber cables can extend to five times their original length, and usually, they are available in black color.

Retracted length/ Extended length

When retracting, the length of the curly cords is the same as its available length (not stretched out). Here you can stretch it to a maximum of 5m. When you extend it to the farthest, it is the extended length.

When calculating these dimensions, you must additionally account for the cable’s aspect ratio.

• PVC – 3.5:1
• PUR – 4:1
• Rubber Band – 5:1

What type of tails/ What length of tails

The straight ends of any curly cable are known as “tails.” Moreover, these can vary in terms of both length and direction. Two of these directions are the Right angle (or tangent) and axial (or straight).

DIY Coiled Wire

DIY coiling stranded wires are simple and can be done with any vinyl covering the wire. Using a heat gun and basic tricks in less than 10 minutes, you can transform any straight stranded wire into a spiral one.

Now, you will wonder why stranded wires and not solid ones. The answer is simple; as stranded 

wires are more flexible, they can curl without breaking the core conductor. On the other hand, the solid wire has one single core that does not accept bending and can break.

So let’s see what you will need to have on your hand.

Material Needed

• Dowel or stick around which you will form a coil
• Electrical Drill
• Cable Cutters
• Heat Gun
• Pliers

Method

• Secure one end of the wire on the dowel with the help of tape. Later, you can cut the straight end or join the plug with it.
• Start wrapping the wire from the fixed end tightly on the dowel stick. Keep pushing the winds next to each other as you proceed further. Moreover, you can do the work either clockwise or anti-clockwise.
• At the end of wrapping, secure the other end of the wire on the dowel with the help of tape.
• As the wrapping is done, you will now heat it using a blow dryer or heat gun. Now, you don’t want to melt the sheathing, so you need to maintain a good distance from the wire. Also, uniformly distribute the heat by the constant movement of the gun.
• After a few minutes, you will see that the jacket is becoming shiny. It has now become a spiral and accepted its new shape. Let the wire cool down, and then remove it from the stick.
• In the end, inspect the wire for any scratches and burning signs. That way, you can ensure that the quality of the wire is not compromised and is ready to go.
• And there you have it; your DIY coiled wire.

Caption: Spiral wire 3D illustration

What to Consider When Designing Specific Curly Cords 

If you are an OEM searching for a long-lasting coiled cord solution, we advise you to consider several factors before placing an order with a supplier.

You should first consider the setting in which you will be using the cables. Designing a curly cord for an industrial setting differs from designing one for a medical or retail setting.

Then, determine the lifespan and level of activity you desire for your ringlets. If, for some reason, you need coiled cords with a lifespan of 100,000 cycles, you’ll want to make sure those requirements are baked into the design from the start.

Another example would be if you needed your curling cords that will last forever and be put through 30 washes a day, you’d want to be sure your supplier could accomplish that. In one extreme case, a coiled cord must withstand 500 motions daily for an entire month (15,000 cycles total).

Conclusion

Curly cords are important in places where you need durability and mobility. While compacting the wire’s length, they do not break when pulled extensively. There are different conductors diameters from which you can choose the cord. After determining the conductor diameter and number of cores, you must select the insulation and sheathing materials best suited to the application. Custom orders for the spiral’s retracted length are possible up to 5 meters in length. Moreover, you can make it at home with simple stranded wires and use it for your next wire harness project. Here at Cloom, we offer any wiring harnesses and cable assemblies to make your connection safe and reliable.