During the dog days of summer walleyes tend to relate to deep structure or scatter across basins and flats as they chase the bait fish. With scattered fish, locating them can be challenging and frustrating. When faced with this situation, I like to cover as much water as possible which means lead core trolling is the name of the game. Many think lead core fishing is a complicated process, but it is a relatively easy thing to do.   For those unfamiliar with lead core, it is a line with two parts, an exterior sheathing that is woven around a lead wire core. The main advantage and the reason I use lead core during the middle of summer is it allows me to get crank baits down to any depth I would like without having to use heavy weights, deep divers or down riggers. Well now your probably thinking how do I know how much line to let out? Well, lead core changes colors every 10 yards allowing you to gauge how many colors to let out in relation to water depth. The rule of thumb is 4-5 feet of depth to every color of lead core, so about 3 colors if you are fishing in 15 feet of water depending on lure, leader length, wind, and trolling speed. Lead core comes from 14lb to 45lb test, but due to its visibility a fluorocarbon leader 10 to 20 feet is used to attach the artificial baits.   When it comes to a good lead core rod I like the St. Croix Eyecon trolling series rod. This has a tip that is sensitive enough to ensure the bait is running properly, a soft tip to absorb strikes, yet is backed by a strong durable backbone allowing you to land a fish of any size. For the states that allow two rods to be used I use the combination of 5' rods off the back and 9' off the sides. Paired with my Eyecon rod I like to use Cabela's DepthMaster reels to hold the lead core. These reels are extremely durable and come standard with a line counter allowing me to get my bait in the sweet spot time and time again.   As far as the rest goes, use your locator to find those deep structures, basins, or expansive flats. In these areas you should see bait fish at various heights in the water column on the screen of the locator. By using this tactic you should be able to pattern walleye's on any lake you are fishing, learning the magic color and the perfect depth to be running. With a little trial and error you will become a proficient lead core fisherman. So try this tactic out and you will be impressed with the results.  Good Fishing.