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2. Strip approximately 1½ inches from each broken end of the wire. 

3. Lay the stripped ends side by side and twist one wire around the other with approximately four turns. 

4. Twist the free end of the second wire around the first wire with approximately four turns. Solder the wire turns together using 60 ⁄ 40  tin-lead resin-core solder. 

5. When solder is cool, draw the sleeve over the soldered wires and tie at one end. If potting compound is available, fill the sleeve with potting material and tie securely. 

6. Allow the potting compound to set without touching for 4 hours. Full cure and electrical characteristics are achieved in 24 hours. 

## Connecting Terminal Lugs to Terminal Blocks 

Terminal lugs should be installed on terminal blocks in such a manner that they are locked against movement in the direction of loosening. [Figure 4-109] 

Terminal blocks are normally supplied with studs secured in place by a plain washer, an external tooth lockwasher, and a nut. In connecting terminals, a recommended practice is to place copper terminal jugs directly on top of the nut, followed with a plain washer and elastic stop nut, or with a plain washer, split steel lockwasher, and plain nut. 

<img src='content_image/578217.jpg'>

Aluminum terminal lugs should be placed over a plated brass plain washer, followed with another plated brass plain washer, split steel lockwasher, and plain nut or elastic stop nut. The plated brass washer should have a diameter equal to the tongue width of the aluminum terminal lug. Consult the manufacturer’s instructions for recommended dimensions of these plated brass washers. Do not place any washer in the current path between two aluminum terminal lugs or between two copper terminal lugs. Also, do not place a lockwasher directly against the tongue or pad of the aluminum terminal. 

To join a copper terminal lug to an aluminum terminal lug, place a plated brass plain washer over the nut that holds the stud in place; follow with the aluminum terminal lug, a plated brass plain washer, the copper terminal lug, plain washer, split steel lockwasher and plain nut or self-locking, all metal nut. As a general rule, use a torque wrench to tighten nuts to ensure sufficient contact pressure. Manufacturer’s instructions provide installation torques for all types of terminals. 

## Bonding and Grounding 

Bonding is the electrical connecting of two or more conducting objects not otherwise connected adequately. Grounding is the electrical connecting of a conducting object to the primary structure for return of current. Primary structure is the main frame, fuselage, or wing structure of the aircraft. Bonding and grounding connections are made in aircraft electrical systems to: 

1. Protect aircraft and personnel against hazards from lightning discharge, 

2. Provide current return paths, 

3. Prevent development of radio-frequency potentials, 

4. Protect personnel from shock hazard, 

5. Provide stability of radio transmission and reception, and 

