Strip insulation; insert wire and crimp heat-shrink ring eye; apply heat and seal.

When you move up to the bigger wire sizes needed for main battery cables, starter motor wiring, or to connect an electric windlass, things change somewhat. Starting at No. 8 wire and larger you’ll need to find a large swaging tool and install your own section of heat shrink over a bare connector. I’ve found the best place to make up these heavy cables is at a West Marine store or other marine chandlery that gives customers access to an array of the appropriate lugs, various colors of heat-shrink tubing, and most importantly a large swaging tool with properly sized jaws.

Make the connection with big wires the same way as with the smaller ones. Select the proper size ring eye lug for the job and then strip off just enough insulation so the bare wire fills the lug. Next, using the right size jaws, crimp the lug tightly to the wire. Now slide on a piece of adhesive-lined heavy walled shrink tubing color matched to the insulation and use a heat gun to shrink it in place. The heat-shrink tubing will seal out water as well as strengthen the mechanical connection between the wire and the lug.

The last thing to remember when making connections on any boat wiring is to properly bundle and secure it. Start by forming tight bundles with your hand and then secure them with plastic tie wraps. Finally, use tie wraps or plastic wire hangers secured to solid bulkheads with screws to hold wire bundles in place and prevent jolt or vibration damage.

If you use the right wire, make watertight connections, and securely fasten all wires in place, your electrical system will provide years of trouble-free service.

FS