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I have just received a PM message asking about hunting, so I decided to post my answer: Hunting In my early days on TU, I too found old threads on hunting, and I was very intrigued. The message then was that it was not a designable feature, but more pot-luck. There was even talk about harnesses made from brass wire produced more hunters. But, as an engineer, I knew all the above was nonsense, and so I set out to explain the cause of hunting and solve the riddle of building hunters with consistent success. This took many years and became an obsession. All lipped crank-baits are capable of hunting. It is just a case of finding the speed at which this occurs. I am sure you have noticed when you rip the bait through the water, sometimes it deviates to one side. You would probably dismiss the anomaly as a quirk, a water current issue, a fault in your lure build or it must have struck a bit of weed or a leaf and was thrown out of kilt. All these explanation, although plausible, were unlikely. You probably touched the transition speed briefly were hunting occurs. Hunting (zigzag motion) is a function of lip length, lip angle and retrieval speed. Theory 1 - The angle at which a lure swims in the water at a constant speed is determined by a balance between the lip and the back of the lure, all pivoting around the tow eye. Forces above the pivot point (eye) balance the forces below the pivot point and result in a swim angle and balance. 2 – The forces over the sharp edges of a lip are stronger than over a blunt or round surface. As speed changes, the forces over the lip change at a different rate to those over the blunt back of the lure. This difference in forces changes the swim angle of the bait; as the lure moves faster, the lip forces increase more than the back forces, this results in a steeper swim angle. 3 – as the angle of the lure increases there comes a point where the lip is perpendicular to the tow direction. The forces on the lip are now at their maximum. Any further increase in speed would try to force the lip beyond perpendicular and the effective lip exposure would be reduced. The reduced lip force has to balance the back force and results in a smaller angle. And so the lure ‘nods’ or ‘porpoises’ up and down. 4 – as the lure approaches this critical angle it just does the occasional nod. This interferes with the waggle. Think of it as replacing a single waggle motion with a nod motion. When you lose one waggle say the left side, then the lure receives a double waggle on the right side. This forces the lure to change direction. 5 – Now the lure is now swimming at an angle to the tow direction in plan-view. The forces on the edge of the lip facing forward are stronger. When the lip once again reaches the critical angle, the strong side triggers the nod and so the weak side gets two waggles and so the lure changes in the opposite direction, hence the zigzag motion. Design 1 - If the lip length is short, the transition speed will be high, and you may well never observe the hunting phenomena. 2 – If the lip angle is too shallow, the whole lure would be swimming perpendicular to the tow direction. The lure would likely blow out before the transition is reached. In any case, the swim angle would be beyond the optimum dive angle and the lure would swim shallow but with a large thump due to the large diving lip fighting against the water. And so, hunting lures are shallow to medium depth lures only. The trick is to design the lure so that it hunts at the speed that you want to retrieve the lure. Retrieval speed – I like 2-cranks of the handle per second as a comfortable speed. Keep in mind that the hunting is only going to occur at one speed. Slower and the lure will give the regular waggle, faster and the lure will porpoise continually and possibly blow out. Lip angle – I design my hunters with a lip angle of between 45° and 60° to the horizontal. A steeper lip angle will reach the transition sooner than a shallower angle, but the depth of swim will be shallower. If you want a slow, sub surface hunter, then a 60° or even higher will do the job. If you want a little more depth, a 45° or even less will give you say 4’ – 6’ but you may have to retrieve faster. Build Obviously a test tank large and wide enough would be ideal for testing, but a battery powered Dremel at the lakeside will do the job. Make the lip too long, so that there is no waggle. If you look closely enough you will observe the porpoising effect. Gradually trim the lip length back until the hunting starts. There is a lip length tolerance for the hunting effect, the trick is to stop trimming at the maximum hunt, but the only way to know what is the maximum is by trimming more and losing the maximum. I build my lures 10 at a time. I waste the first one to find the maximum hunt effect and then trim the rest accordingly. The trim operation must be on the final assembly; with hooks and topcoat. I suggest one or two lures without the fancy paint job, but they must have hooks fitted and the same top coat. Dave