Fiber Cleaver – Key to Quality Connectors and Splices

Updated on Sep 7, 2018 by

In the field of fiber optics, it is very necessary to use fiber optic cables with clean and smooth end face. The fiber optic cleaver is a crucial tools for low-loss and low-reflectance fiber optic splices or terminations, especially when using the pre-polished connectors with internal splices. The fiber cleaver usually work in conjunction with fusion splicers to do optimum splicing jobs, and is the key to quality connectors and splices.

What Is Cleaving and Fiber Cleaver?

Cleaving is the process by which an optical fiber is “cut” or precisely broken for termination or splicing. Just like cutting glass plate, fiber is cut by scoring or scratching the surface and applying stress so the glass breaks in a smooth manner along the stress lines created by the scratch. Properly done, the fiber will cleave with a clean surface perpendicular to the length of the fiber, with no protruding glass on either end.

A fiber cleaver is a tool that holds the fiber under low tension, scores the surface at the proper location, then applies greater tension until the fiber breaks. Good cleavers are automatic and produce consistent results, irrespective of the operator. With good fiber cleavers, you only need to clamp the fiber into the cleaver and operate its controls, then fiberglass is cleaved automatically. However, some cleavers are less automated and require operators to exert force manually to cut the fiber cable, which makes it difficult to predict and control the force. The good cleavers are called as precision cleavers, while the less automated ones are called as cheap or scribe cleavers, which will be introduced in the next part.

fiber cleaver

Two Types of Fiber Optic Cleavers

As mentioned before, fiber optic cleavers can be classified into precision cleavers and cheap or scribe cleavers.

Scribe Cleavers

The scribe or manual cleaver, which is cheaper than the precision cleaver, is the most original type of fiber optic cleaver. Scribe cleavers are usually shaped like ballpoint pens with diamond tipped wedges or come in the form of tile squares. The scribe has a hard and sharp tip, generally made of carbide or diamond, to scratch the fiber manually. Then the operator pulls the fiber to break it. Since the breaking process is under manual control, it is hard to control the force, which makes the cleaving less accurate and precise. That’s why most technicians shy away from these cheap cleavers.

Precision Cleavers

As the name implies, precision cleavers can do a preciser cleaving job compared to the scribe cleavers. A precision cleaver uses a diamond or tungsten wheel/blade to provide the nick in the fiber. Tension is then applied to the fiber to create the cleaved end face. The advantage of the precision cleavers is that they can produce repeatable results through thousands of cleaves by simply just rotating the wheel/blade accordingly. Although they are more costly than scribe cleavers, precision cleavers can cut multiple fibers with increasing speed, efficiency, and accuracy. As the fusion splicers became popular, precision cleavers were developed to support various splicing works. Precision cleavers are deal for fusion splicing standard 125/250um & 125/900um fibers and preparing fiber for various pre-polished connectors.

How to Use A Fiber Cleaver?

A fiber cleaver utilizes an automatic anvil drop for fewer required steps and better cleaving consistency. The automated anvil design can save time and significantly improve the quality of the cleave by eliminating human error and subpar cleaves associated with scribes and manual cleavers. To perfectly cleave optical fibers, perform the following steps:

Step 1: Open the body cover and put the stripped fiber on the v-groove. Step 2: Close the holder cover. Step 3: Close the cover and move the slider forward to cleave the fiber. Step 4: Open the cover and check the cleaved fiber. Step 5: Open the holder cover and take out the cleaved fiber. Step 6: Remove the chip of cleaved fiber with a pair of tweezers.
Operation Procedure for Fiber Cleavers

Tips on Choosing Fiber Cleavers

1.Select fiber cleavers according to your application requirements. Fiber cleavers, designed for fusion splicing, need a low average angle that is one degree or less, whereas cleavers appropriate for mechanical connectors require angles below three degrees. So determine whether you require a single-fiber or multi-fiber cleaver before you cleave the fibers at one time.

2.Think twice before purchasing a cleaver built into a splicer. If you intend to purchase the built-in cleavers, you must check whether the cleaver or splicer requires maintenance. It may cause inconvenience to technician if they loses valuable tools, which can hold up the job at hand.

3.Purchase a cleaver with the latest automation features that can save a lot of labour and time. Fiber cleavers are always continuing to evolve with new and improved features, such as automated fiber scrap collection, automated scoring mechanisms, and the latest automatic blade rotation technology.


Precise cleaving is the premise of successful fusion splicing. Thus the quality of the fiber cleavers directly determines the quality of fiber optic splices or terminations. If the fiber ends were not cleaved perfectly, fiber loss would occur which would in turn affect the transmission of signals. To buy reliable and high precision fiber cleavers, please visit www.fs.com or contact us via sale@fs.com.

Related Articles: Fusion Splicer: A Good Helper for Fiber Optic Splicing How To Repair the Accidentally Cut Fiber Optic Cable?

You might be interested in

See profile for Sheldon.
Decoding OLT, ONU, ONT, and ODN in PON Network
Mar 14, 2023
See profile for Irving.
What's the Difference? Hub vs Switch vs Router
Dec 17, 2021
See profile for Sheldon.
What Is SFP Port of Gigabit Switch?
Jan 6, 2023
See profile for Migelle.
PoE vs PoE+ vs PoE++ Switch: How to Choose?
May 30, 2024
See profile for Moris.
How Much Do You Know About Power Cord Types?
Sep 29, 2021