How to Choose Fiber Optic Cleavers

By Contributed Article | April 13, 2015

Commonly overlooked when making a fusion splicer purchase, fiber optic cleavers are crucial tools that ensure perfectly smooth fiber ends. Sumitomo Electric Lightwave offers tips on how to choose fiber optic cleavers.


Sumitomo’s FC-6RM-C is an automatic blade rotation multi-fiber cleaver for one to 12 fibers with a built-in fiber scrap collector.

Sumitomo’s FC-6RM-C is an automatic blade rotation multi-fiber cleaver for one to 12 fibers with a built-in fiber scrap collector.

The fiber cleaver is a tool commonly overlooked when making a fusion splicer purchase. Just ask any technician who has worked the late shift or faced that rush splice job how stressful a poorly functioning cleaver can be. Since a perfectly smooth optical fiber end face is crucial for a successful low-loss, low-reflectance fusion splice or termination, the following tips are useful when making a new cleaver selection.

  1. Select a cleaver that meets your application requirements. Cleavers that are designed for fusion splicing require a low average angle that is one degree or less, while cleavers appropriate for mechanical connectors require angles below three degrees. Determine whether you require a single- or multi-fiber cleaver that can precisely cleave one to 12 fibers at a time.
  2. Purchase your cleaver from a reputable manufacturer or distributor. Tempting eBay and Craig’s List offers of cleavers at highly discounted prices abound on the Internet. As with fusion splicers, there are a host of illegitimate knock-offs that replicate the body, look, and branding of the leading manufacturers’ cleavers. Look at the inner components and you’ll likely find cheaply made parts and blades with inferior metal alloys that can compromise your splice or break down during the job. By purchasing from reputable manufacturers, you’ll enjoy manufacturer support and warranties; service for periodic maintenance and cleaning that extends the life of the cleaver; and a cleaver made of the best durable metal materials.
  3. Think twice before purchasing a cleaver built into a splicer. The downside to these built-in cleavers is that if either the cleaver or splicer requires maintenance, the technician loses two valuable tools, which can hold up the job at hand.
  4. Purchase a cleaver with the latest automation features that save time. Cleavers, like fusion splicers, continue to evolve with new and improved features, such as automated fiber scrap collection, automated scoring mechanisms, and the latest automatic blade rotation technology.

Automated features save time and significantly improve the quality of the cleave by eliminating human error and subpar cleaves associated with scribes and manual cleavers:

Automatic Fiber Scrap Collection

Manufacturers now offer cleavers with fiber scrap catchers that automatically collect fiber scraps. These cleavers not only collect the fiber scraps, but also store the scraps in internal trash bins, ultimately saving cleaning and safe disposal time for the technician. As a standard safety practice, fiber shards should always be collected and disposed of properly, since fiber can easily embed into the skin.

Automated Scoring Mechanisms

Due to automated scoring mechanisms, cleavers can now complete a cleave and reset themselves for the next cleave in one or two steps, streamlining the cleaving process while perfecting the quality and reliability of the cleave. Manufacturers now offer handheld clamshell-designed cleavers that complete the cleave with a quick and easy press-and-release motion.

Automatic Blade Rotation Cleavers

This feature is one of the breakthrough technologies in cleaver design. The automatic blade rotation system automatically rotates the cleaver blade during use for easy, fast, and precise cleaves in a two-step process that prevents double scoring of fibers and solves the field technician’s challenge of manually adjusting and rotating the cleaver blade position.

Standard cleavers cleave the fiber using the same blade position until that position becomes dull, resulting in poor cleaves. When this occurs, the technician must rotate and adjust the blade height, which can be a very time-consuming process. Typically, with standard cleavers, the blade rotation process requires loosening a set screw and turning the blade to the next blade position. The height adjustment also requires loosening a different set of screws and raising or lowering the blade until it is in the optimal position, which can be determined by viewing the cleave angles on the technician’s fusion splicer. If the angle is not achieved, the process must be repeated.

In the past, the difficult process of blade rotation adjustments has necessitated increased service and maintenance of the fiber cleavers due to the frequent improper cleaver blade rotation and height adjustments.

Cleavers with automatic rotating blade systems utilize the complete blade surface (unlike standard cleavers) and automatically increment the cleaver blade with each cleave. These auto-rotating cleavers remove the majority of the cleaver maintenance drudgery; provide 48,000 consecutive cleaves with no adjustments necessary; and extend the life of the cleaver blade; while resulting in an excellent typical cleave angle of <0.5 degrees.

Quality optical-fiber cleaves are a must for maintaining optimum cable and connectivity performance. Cleavers may be small, but they are one of the most important items purchased for the tool box.

Dwayne Holst is product manager at Sumitomo Electric Lightwave.

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