Start by getting the most current issue of Precision Trolling.Closest thing to the trollers bible that you can have. Then go practice! There are so many variables to getting depth out of a crank bait, starting with line. I’m a devoted fan of fireline. I use 10# on my 27LCs. I have heard that you can get anywhere from 10-25% more depth out of fireline then mono due to the smaller diamater. I believe that is different with every crankbait. For example, I won’t leave home without Thunder Stick Jrs. Precision trolling says with 10# Trilene XT, you can get this lure 18′ deep with 220′ of line out. You can achieve this same depth with 180′ of fireline out, but you can’t gain much more depth, regardless of how much fireline you let out, ( at 1.7-2.0 mph). I use fireline because I believe I get more hook sets than with mono. Just have to leave your drag light so you don’t pull out. Next consideration is speed. Once again, each bait is different. Some reach max depth at 1.5, (and start coming up), some at 4.0. Some “spin out” at certain speeds.
There are lots of “trick” ways to get crankbaits down to where the fish are. A lot of guys on this site love lead core. My experience is limited, although I have been using it more and more. This summer I fished Erie and caught fish over 70′ of water using 10 colors of lead core with 1/2 oz rattle tots at 2 mph. I figure the lure was running about 50′ deep, right where we were marking fish.
Personally, I like three ways and snap weights to get cranks down. Just the methods I’ve used alot and feel comfortable with. I find large flats, deep and shallow, and spend hours just running different cranks over them. Thats the only way I know to get familiar with the many variables. Like so many things, the more you do it, the better you’ll get. Hope that helps. Keep it vertical.
