When used in reference to soft baits, the term “buoyancy” means the lure’s tendency to float. All soft baits should have high buoyancy, meaning they will touch the water’s surface when not weighted down with terminal tackle. This buoyancy will help the lure rise up off the bottom and make itself visible to fish. It will also give the soft bait the appearance of life by constantly pulling itself toward the surface of the water.
What is Buoyancy?
In technical terms, a lure’s buoyancy is equal to the weight of the water that it pushes out of way, or displaces. This means that as long as the lure weighs less than the water it is sitting directly on, it will float. Air can be added to a lure to make it weigh less and thus float. Likewise, flakes and metal can be added to make it weigh more and thus sink.
How To Change a Lure’s Buoyancy
A soft plastic lure’s buoyancy can be changed by adding air, cork, metals, or other materials to the soft plastic. As a general rule, adding items that already float (air, cork, etc.) will make the lure more buoyant, while adding items that naturally sink (metal shavings, clay, …) will make the lure less buoyant.
Designing Soft Plastics with Buoyancy
Typically, you will want your soft plastic to naturally float. This is because most anglers will use either a Carolina or Texas rig when fishing it. Since both of these techniques involve the addition of weights, you will need your lure to rise up off the bottom and combat the force of the weights. Alternatively, many tacklemakers play around with their lure’s buoyancy to make certain portions of the lure rise up higher than the others. An good example of this is the “Defensive Stance” for soft plastic craws. In this design, tiny air bubbles are added to the claws of the crawfish to make them float above the body. This gives the craw the realistic appearance that fish expect.