Spinnerbait

A spinnerbait refers to any one of a family of fishing lures that get their name from one or more metal blades shaped so as to spin like a propeller when the lure is in motion, creating varying degrees of flash and vibration that mimics small fish or other prey. The two most popular types of spinnerbaits are the 'in-line spinner' and 'safety pin' spinnerbaits, though others such as the 'tail-spinner' also exist. Spinnerbaits are used principally for catching predatory fish such as perch, pike and bass.

Spinnerbaits attract predatory fish primarily by activating a special sense organ called the lateral line system through the spinning blade. The Lateral line system enables fish to "touch" and ‘feel’ objects at a distance. Most fish have well-developed sense of touch and can feel the slightest change of water flow around it as a series of vibrations which may warn fish of approaching dangers or indicate the location of prey.

Spinnerbaits can also stimulate other senses of fish to mimic prey by creating flashes in the water (sight) and by creating sound waves in the water (hearing).

The in-line spinner is named for the fact that a metal blade revolves around a central axis (a wire), which may be attached by a clevis (a c-shaped metal piece with holes that accommodates the wire) or by itself. Most in-line spinners have metal weights rigged behind the spinning blade and beads or brass hardware that separates the two for frictionless spinning. Due to the fact that the spinning blade cause the whole bait to rotate, line twist builds that creates line problems and tangles. Swivels are used to solve the problem of twist.

As with all spinner type baits, various shapes of blades are used depending on many factors. Speed of retrieve is a major consideration because different blade designs revolve at different speeds. For example, the elongated willow leaf design requires the most speed to start and maintain the spin. The broader and more circular Colorado blade requires less speed and a slower retrieve to maintain spin. An Indiana blade falls somewhere in between. Vibration is higher with broader blades, less with streamlined blades, but flash depends more on blade size, texture and color than on design.

A hammered nickel (pock-marked) blade has the most flash in that the dimpling reflects light at more angles than a smooth polished blade. Painted blades can have more or less flash depending on color and patterns, but always less flash than silver finishes under a sunny sky and have more flash under low light conditions. Under low light conditions fluorescent colored blades stand out over regular colors or polished metal.

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Wikipedia