A sliding bobber allows a live bait to be fished at any desirable depth without effecting an anglers rod and reel casting capabilities. Bobber, float, or cork; whatever terminology an angler uses to describe them, odds are the first fishing pole you ever had in your hands had a float attached. Remember how as a kid the excitement built as a bobber began to move knowing a fish was after the bait. Even today odds are that same excitement begins to build as your float disappears below the surface. Using a cork is as old as fishing itself. Most often simply attaching the float in a fixed position works just fine, as when fishing for largemouth bass using a golden shiner or bream fishing using earthworms. But when using baitcasters or spinning reels and the bait needs to be fished more than six or seven feet deep, casting with a fix bobber becomes a problem. This is when a sliding bobber rig is essential.
The concept is simple. Slip a bobber on the fishing line so the bobber can freely slide up and down the line. Most of these types of sliding bobbers have pegs which are hollow specifically designed for that purpose or the bobber itself will have a hollow center just large enough to allow the fishing line through.
The bobber is stopped at the angler's desired depth by a "bobber stopper". Most often a bobber stopper is nothing more than a soft piece of string tied in a tiny knot just large enough to catch the bobber. This prevents the bobber from sliding any farther up the line. The weight of the sinker pulls the bait down to the desired depth thus allowing the bobber to keep the bait suspended there. When the fisherman reels in the line, the bobber slides down toward the hook. This makes casting much easier and is especially effective when using live bait. Different styles of Bobber Stoppers are sold commercially but they all basically work the same.
The simplest of sliding bobber rigs can be made from things found is most tackle boxes. Slip on the bobber stopper and bead, remove the plastic sleeve, then pull the string into a tight knot, and trim off the end of the string. Any bobber that has hollow pegs can be used, crimp on a couple of standard sinkers and tie on the hook. If you have no bobber stoppers and are desperate, try a strip of rubber skirting from an old spinner bait or a small rubber band. These must be tied tightly and just large enough to catch the bobber. This should get you by for the day.
When fishing for large fish such as striper, spotted sea trout, or redfish, a strong leader is generally needed. Below is an example of a solid sliding bobber rig. The leader should be at least 30 pound test and of course, the heaver the sinker, the larger the float required. A heavy sinker may be necessary in strong currents. The protective beads help shield the knots from wear and tear.
One more tip. Several style of bobbers are weighted to make them stand upright in the water. These are find and work well. However, unless the weight of the sinker itself is holding the bobber upright there is no way to be sure the bait is not resting on the bottom.