Since man began tying pebbles to his fishing line, there has been a quest to get lures and baits deeper and deeper.
Years ago, this was mainly accomplished by adding lead, and lots of it. Lead weights of over a pound certainly take the lure down, but they do leave something to be desired as far as ease of use. First, the lead must be reeled in with the fish, losing any fight the fish may give. Second, the depth achieved by lead corresponds directly to the speed, line out and size of the weight.
Over the last few decades, there have been major advances in getting deeper.
The most popular inline method of achieving more depth is the Luhr Jensen Dipsy Diver. Since its introduction years ago, the Dipsy has produced fish around the globe. This diving plane is also directional, allowing the disk to take the lure to the side as well as down. This allows the angler to run several rods off one side of the boat. All Dipsy Divers, with the exception of the #3/0 size, have a release to ease retrieval. Dipsy Divers are available in sizes 3/0 (cookie) #0 (small), #1(large), and #3 (magnum). Dipsy Divers pull hard, and anglers who use the larger sizes rely on medium-heavy to heavy rods to handle the strain.
Big Jon offers Mini Diver Disks and Deep’r Diver Disks. These are smaller diving planes that dive to 30 or 45 feet depending on the model. Since they do not pull as hard as the larger disks, they can be used with more traditional gear. They can also be trolled behind planer boards.
The Jet Diver from Luhr Jensen is popular, particularly when fished from planer boards. It is unique in the fact that it floats at rest. This prevents snags on inside turns where traditional divers will sink to the bottom. The Jet Divers are not directional and troll straight behind the rod tip or planer board. They are offered in 10, 20, 30, 40, & 50 models, each designating the depth they will achieve with 100 feet of line out.
All inline diving planes are designed for use with lures that dive little on their own. If a deep diving lure is used, it can ruin the balance of the diving plane, actually causing a loss of depth. Diving planes can be used with monofilament, but super lines such as Berkley FireLine and PowerPro are becoming more popular. This is due to the fact that the smaller diameter braids allow the diver to dive much deeper. Also, because the super lines have very little stretch, they transmit bites much better than the higher stretch mono. Stranded wire, such as SurfStrand, is popular when trying to obtain maximum depth from a diver. Wire is even more sensitive than super line, however, it is a bit more difficult to use and protect from kinks.
Lead core line, such as FishUSA’s Stealthcore Lead Core, has recently shown a surge in popularity. Lead core is simply a lead wire encased in a sheath of braided Dacron. The line changes color every 30 feet. Typically the line will add 5-6 feet of depth for each color let out. 10 color lead core line is known as a full core and 20 color is known as a double core. Lead core is offered in many pound tests. All sizes dive to a similar depth, but the difference is in the strength of the Dacron sheath. Lead core can be used with diving plugs and crankbaits, or with spoons and other lures that do not dive on their own.
Copper wire has also recently become popular. Its use is similar to lead core, but it dives approximately 30% deeper. Copper has become especially common for salmon fishing on the Great Lakes where the need to get deeper is more important than ever.
By using these methods to achieve greater depths, anglers are now able to efficiently troll at depths their grandfathers could have only dreamed of, and with much less strain.