The simplest method: connect two cables pre-connectorized via a coupler (also called an adapter). In this guide, we cover the basics of fiber optic splicing, how to perform splicing using two different methods, and finally some best practices to perform good fiber splicing. What is Fiber Optic Splicing and Why is it Needed? – #1. Use and Maintain Your. An Optical Fiber Fusion Splicer is a high-tech machine that uses heat to melt (or “fuse”) the ends of two optical fibers together. Once melted, the fibers are joined into one continuous piece. Here's how it works step by step: 1. For network managers and technicians, a poor splice can lead to significant signal degradation, network downtime, and costly troubleshooting. All students and instructors must wear safety glasses in this lab.