If you have ever spliced optical fiber then you know what a fiber optic cleaver is. If you are new to fiber, then the mention of a cleaver may be a new concept. In simple terms, a cleaver is used to cut your fiber so you have two ends that will line up and can be welded together using a fusion splicer or they can be brought together in a mechanical splice. Fiber optic cleavers are essential tools when splicing and putting connectors on in the field. There are different brands of cleavers and they all have different looks but they all perform the same job. If you are used to a certain manufacturer and you like them, then you should stay with them. When you buy a splicer kit it usually will include a precision Fiber Optic cleaver. When we talk about cleavers, there are several features and different types for you to consider. We will discuss these in the article below.
Different Types of Cleavers
The two main types of cleavers are field cleavers and precision cleavers. Field cleavers are also known as beaver cleavers. These cleavers are used primarily for Multimode fiber applications and they are sometimes used with quick term connectors. When using this kind of cleaver you will press the blade down on the fiber to score the glass and then bend the “tail” to break the glass fiber.
On the other hand, there are precision cleavers. These cleavers are used for fusion splicing and when terminating single mode fiber with quick term connectors. A precision cleaver makes a perfect flat cut, leaving a 90 degree cleave angle on the end of the fiber. It prepares the fiber so that it is ready to splice two pieces together. There are several different manufacturers and with that also some different features and slightly different looks. In the end, they all have the same goal of getting a fiber ready to splice or put a quick term connector on.
Steps to Follow When Cleaving
When you are using either style cleaver, field or precision, there are common steps that will need to be performed before you cleave. The first step is to remove the outer most jacket of the cable you are working on. To do this you will use a tool called strippers. Once you have removed the jacket(s) from the fiber, then you have to get the acrylate coating off of the fiber. This is a coating layer that is put on the glass which allows the fiber to be handled and put on a spool without breaking. As the acrylate coating peels off, you will see it almost curl like when scooping ice cream. This step is critical. Make sure all of this acrylate fiber coating is removed. If any of this coating is left on the fiber, when you go to cleave it, it will make it seem like the cleaver is not working properly. I have had a number of tech calls that start out with “My cleaver is not working properly; I need a new one.” The first question I ask is “Did you go back over your fiber with the 250um slot in your strippers?” Normally you hear silence at the end of the line, then they say thank you and they will call if something else is wrong. You usually do not hear back from that person. So make sure that you remove all of the acrylate coating. Once this is done then you use your alcohol or other fiber optic cleaning solution and wipes to clean off the fiber. If it is cleaned properly, you will hear it squeak while you run the wipe with alcohol over the bare fiber. Always clean the fiber before you cleave. Never clean the fiber after you cleave it because it is very likely that you will damage the end of the fiber.
Types of Precision Cleavers
Precision cleavers work in a variety of ways. There are three step cleavers that require technicians to go through three steps in order to cleave the fiber. These steps usually include closing the lid, pushing the cleaver blade to cut your fiber, and then opening the lid to remove the cleaved fiber. There are one step cleavers where all you do is push the lid down and the cleaver will do everything else, including sliding the cleaver blade and moving the piece of glass into your scrap bin. These kinds of cleavers have helped to speed up the process, and make it easier to prep your fiber for splicing.
When using a cleaver there are a couple of things that you need to pay attention to in order to maintain the cleaver. One of these maintenance tasks is the rotating of the cleaver blade. A cleaver blade has up to 16 different positions that are used and each position has a limit on how many cleaves it can perform well. Each position is good for roughly one thousand cleaves. So every thousand cleaves the blade should be rotated to a new position.
Auto Rotating Blades
Most recently there have been upgrades to cleaver technology that assist to extend the life of a blade, as well as making it easier on a tech to maintain. One of these features is an auto rotating blade. This assists in making sure that the blade is used evenly and it will help to extend the life of the blade. How it works is that every time you make a cleave on a piece of fiber the blade automatically rotates to the next position on the blade. This will help extend the life of a blade.
There are times when you will cleave on a set position and it will get worn quickly or produce bad cleaves and force you to rotate the blade before you get the thousand cleaves in the one position. By auto rotating it helps to eliminate one position getting worn down too quickly.
Another feature that has been added to some of the newer cleavers is the Wi-Fi/Bluetooth feature which allows the cleaver to “talk” to the splicer. The splicer keeps track of the cleave count. This will tell you when a blade should be changed. If a particular position is throwing bad cleaves, it keeps track to not use a certain position on the blade itself.
In conclusion, cleavers are a very important tool when working with fiber. Make sure to maintain them, and to prep your fiber correctly, and you will have a very successful job and you will save money and time.