FOA Basic Skills

Lesson 4: Fiber Optic Splicing

Objectives: From this lesson you should learn:
How to concatenate* fibers by splicing
Mechanical splicing
Fusion splicing
Mass (ribbon) splicing

*Concatenate is a term used to describe the process of joining two fibers together.

Tools And Components Needed
Fiber stripping tools
Fiber to splice (if at least one is a long pigtail, it will make testing splices easier)
Mechanical splices
Fusion splicer


Splicing is used to concatenate fibers when joining two cables or terminating cables with factory made pigtails (a cable with a connector on one end.) Mechanical splicing uses a small alignment device and index matching gel. Fusion splicing welds fibers together in an electrical arc. Mass fusion splicing or ribbon splicing uses fusion splicing techniques on a dozen fibers or more at one time.

field splicing
Splice tech working onsite in a trailer.

Placing spliced fibers in a splice closure.

The secret to a good splice is good cleaves. Unless the cleave is good, the joint between the two fibers cannot be made properly. Fusion splicers come with high-quality cleavers but some mechanical splice kits use inexpensive cleavers that require practice to make good cleaves. (3M has an interesting low-cost cleaver that is included in their kits that uses a diamond wire to cleave the fibers. You use it about 100 times then discard it. Video on the 3M disposable cleaver.) Investing in a good cleaver will make a big difference in the quality of the splices you make.

Both fusion splicing types seal the fused fibers in a sealed protector. Spliced fibers are placed in a splice tray which is in turn placed in a splice closure. Besides practicing cleaving, you should practice placing buffer tubes and fibers in trays and closures.

Work in a space where you will not be disturbed and avoid distractions. It is important you concentrate on the exercises and follow each step carefully. Allow plenty of time to complete the exercises without interruption.

Lennie works safe Please Note: This is not the usual online course - it is intended to guide you as you learn new skills - the "hands-on" skills needed to install optical fiber cable plants. It involves using tools and components in a realistic manner. Some of the processes here can be hazardous, like working with sharp scraps of optical fiber and chemicals.

In Lesson 1 you should have familiarized yourself with the safety procedures - follow them all the time. Do not work with fiber without eye protection and a proper work area that is easy to clean up.  Always wear safety glasses when doing any of these exercises and dispose of all scraps properly.

As part of Lesson 1, you should have watched the FOA YouTube Video: FOA Lecture 2: Safety When Working With Fiber Optics      

Download a FOA safety poster for your work area.

Background Review
This "skills" course assumes you have knowledge of fiber optic splicing. If you are new to fiber optics, you review the FOA Guide section on Termination and Splicing or should  complete the
Fiber U Basic Fiber Optics: Termination and Splicing course before attempting the hands-on exercises here.

There are many videos showing the installation practices for splice closures on the web, especially on YouTube. The recommended ones are from manufacturers like Corning, PLP (Preformed Line Products), Tyco, 3M, etc. who are using video to show how to use their products.  You can find them by links from the manufacturer's website or searching YouTube or the Internet generally.

Hands-On Lab Instructions

Download the Workbook section on Splicing and the VHO tutorials on splicing linked below. Watch the videos and/or read the references on the termination types you have available for practice. The
VHO  "Virtual Hands On" Tutorials take a "step-by-step" approach to the hands-on processes covered in this self-study program and the videos will show the processes in motion. They are both a good way to teach yourself the processes here - watch the video for the overview then follow the steps in the VHO web pages.

Workbook Section (PDF)
VHO Tutorial (PDF)
Video (YouTube)
Lesson 4: Fiber Optic Splicing Splicing Mechanical
Fusion - single fiber
EasySplicer Step-byStep

Fusion Splicing
Mechanical Splicing

Hands-On Assignments:
After reading the workbook section and VHO tutorial and watching the videos, complete these exercises using all the cable types available to you.

As you finish each section, fill in the worksheet in the back of the Workbook on Splicing. Your completed worksheets are the records of your having successfully completed the exercises.

Fusion splicing workspace
Arrange all your tools, components and other items on your work table. Using a black mat (black Naugahyde works well) makes it easier to see the fiber when working.

Fill in the worksheets at the end of the Workbook section on Splicing as you complete the tasks.

1. Mechanical Splicing

Video: Mechanical Splicing    VHO:  Mechanical   Hands-on lab using crimp splice

Using a mechanical splice, splice two fibers. Use a visual fault locator to optimize the splice. Cleave and repeat several times.

Ultra Splice

2. Fusion Splicing (Single Fiber)

Video: Fusion Splicing   VHO: Fusion splicing - single fiber   Detailed sequential instructions for EasySplicer (shown above)  

Using a fusion splicer, splice two fibers and install splice protector. If you can, test with an OTDR. Try the VFL on the fusion splice. Notice the difference between the fusion splice and the mechanical splice when using the VFL.

fusion splicing optical fiber

3. Ribbon Splicing (Mass Fusion Splicing)

VHO: Ribbon Splicing

Ribbon (mass) fusion splicing. If you have access to a ribbon splicer and ribbons of fiber, splice those fibers. If you have an OTDR and enough fiber to use it, check your splices with the OTDR. Compare the results of the splices for each fiber in the ribbon.

mass fusion splicing

4. Placing Splices In Splice Trays and Closures

After splicing, place the splices in splice trays and then place the trays in splice closures. There are many types of splice closures, so giving directions is difficult. However, the normal way these are used is the loose tube cable is spliced with one tube per splice tray for each cable being spliced and up to 12 fibers, the normal maximum per tube, spliced in each tray.

splice closures

There are many videos showing the installation practices for splice closures on the web, especially on YouTube. The recommended ones are from manufacturers like Corning, PLP (Preformed Line Products), Tyco, 3M, etc. who are using video to show how to use their products. 

Have you completed the Workbook worksheets that are the records of your having successfully completed the exercises?

Test Your Comprehension - Online Quiz On Splicing  

Next:  Lesson 5: Fiber Optic Termination (Connectors)        


Get a "Certificate of Completion" When You Complete The Course
After you complete
complete all six lessons of the Fiber U Basic Skills Lab Fiber Optics online self-study course, you can now take an online exam and, when you pass the exam, get a "Certificate of Completion" for this course. You should complete all lessons including taking the quiz ("Test Your Comprehension") at the end of every lesson. When you think you are prepared, you can take an online exam for a nominal fee ($20) which will give you a "Certificate of Completion" for this course.

Take the Test to Get Your Certificate of Completion For This Course  


Return to Lesson Plan


Table of Contents: The FOA Reference Guide To Fiber Optics

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