lipless swimbait, but...
35 replies to this topic
Posted 12 July 2007 - 10:26 PM
I watched the video, and I somewhat got what you were saying. I think it definitely helps explain baits like crankbaits and chatterbaits, why they wobble side to side. I just don't think it pertains to live fish movement.
Your theory does satisfy every condition, as long as you're talking about the same things happening. You yourself are imparting action to gliders and spooks. The physics of a bait that's simply being pulled through the water and physics of the water itself are mostly what controls the movement of a crankbait. You can make a glider or spook or straight plastic worm do A LOT of different things depending on how you impart the action. With a crankbait, as long as it's balanced so that it doesn't blow out at high speeds, will only do two things unless it hits something, unless you jerk the rod or stop the retrieve. It can speed up or slow down. The speed of the wobble of the bait will be proportional to the speed of the lure itself, but it'll be the same wobble.
That's how your theory satisfies every condition it applies to. I think, however, that it may not apply to them all.
OH, and BTW, this thread has been officially hijacked!!
Posted 13 July 2007 - 12:09 AM
The thread is not hijacked, JR asked the question. But, on the subject, if the lure lies flat, it is probably the ballast drilled too far in, or if a dense wood has been used and the shape of the section is wider at the bottom, the ballast might not be significant enough to bring it to the vertical.
Beautiful lures, would be a shame to have to put a lip on them.
Clamboni, what you say is true, but the rules have to apply to all or the rules don't work. The other theory available is aerodynamic theory. It still applies in water. Example, if one side of the body is curved more than the other, the curve will draw that side further out and the lure will swim a diagonal, but it will never switch direction. I have never managed to work aerodynamic theory to get the lure to oscillate.
In the case of gliders and sliders not having a sharp edge to form a vortex, it is fairly probable that a good vortex is not formed, but a pressure difference will still be generated due to turbulence, having a similar effect, so the vortex theory would at least serve as a good analogy.
In fact both theories are the same. In aerodynamic theory we talk about turbulence. This is just a collection of random eddies or vortices. The difference is that a flat plate will produce a well defined pure vortex, which will in turn provide a predictable outcome, ie vortex shedding (video clip).
On the other hand, vortex theory gives a good explanation for an oscillating condition (vortex shedding). But to be brutally honest, it is not you guys that I am trying to convince, it is myself, so I am very happy to be challenged. I feel that some good will come from this discussion.
Posted 13 July 2007 - 05:27 AM
Vodkaman I think u are obsessed with vortices anyway, I'm positive that the gliders movement is caused by the pressure , while the front of the lure oppose to the water , being heavier and bigger , the tail will move side to side cause it resisting to the pressure caused by the water dislocated by the head, the movement being controlled by the weight of the lure. The use of the lead in the back of the lure could cause a discreet movement (more lead) or a "noisy" movement (less lead), it is all about the tail opposing or not to the water. While the head moves towards one direction, the water flows to the tail which will resist it (more or less depending on it's weight), forcing the body to move in the opposite direction. Just a thought
Posted 13 July 2007 - 05:32 AM
P.S. referring to the first post , doesn't anyone notice that the lure is jointed? I think u can't obtain a glider from a jointed lure because it has an S shape in the water, the "walking the dog" technique is a must for obtaining a movement similar to a glider
Posted 15 July 2007 - 07:31 PM
You are right about the obsession, it's really annoying at times. I used to play both darts and pool, now I only play pool as there are no vortices to think about.
You covered the tail moving from side to side in one sweeping statement. You have to ask 'what makes the tail move from side to side?'. This is the key question. You mention the pressure, if the pressure was constant, why should the tail wag?
Posted 15 July 2007 - 10:25 PM
Noone ever said the pressure was constant. When I posted, I mentioned that I didn't think vortices applied much to a walking/gliding bait. I do think though, that they almost have to have something to do with tail movement on a lipless swimming bait, similar to a crank but with different effects on the bait. LOL Now figure out how they apply to a lipless swimbait so we can make better ones.
When I said that your theory does apply to everything by the way, what I meant to say exactly was that vortices may be present in a walking bait, but they aren't the forces at work that cause the action. So the theory works, as in the bait movement causes a vortex, but the vortex that is caused isn't the reason that the bait walks.
Pikeman, the pressure differences on each side of the bait are caused by the vortices. I don't think that's the reason they walk. I think the reason they walk is that when you pull on the line, you cause the bait to both turn and move forward. Momentum does the rest.
Posted 16 July 2007 - 12:15 AM
Clamboni. The momentum idea is entirely reasonable. It would tie in with the tail weight, adding momentum to carry it past neutral and zag the other way.
I still have not had a chance to view the posted video's, I am presuming the motion under constant retrieval is a slow 'S' action.
Posted 16 July 2007 - 02:01 AM
Clamboni, the question remains why the bait turns when you pull on the line, presuming that the bait is in line it will still turn, I was assuming that when the bait moves forward , the water dislocated by the head flows on the rest of the body putting pressure on it, maybe this pressure is created by Vodkaman's vortices the tail being lighter will become unstable. The problem is controlling this instability for obtaining different types of action, it is a matter of shapes and weight, I think Vodkaman remained without lip material and now is studying gliders as a substitute for cranks:p:twisted:
My first glider : http://www.rapitori....php?pic_id=2930 it was ok, but it worked only on fast retrieve or trolling (the one in the right, the left lure is a popper frog)
Posted 16 July 2007 - 06:56 PM
Above is a link to another video clip sent to me by Clemmy (thank's Clemmy). It is another visual explanation of vortex shedding. I have posted it because it demonstrates that the effect is present without swirls of vortices being present.
Pikemans point about, the lure still turns, even when it starts in line (zero angle). In this instance only vortex shedding could start the side movement. As many members have stated the importance of the rear portion of the ballast, I must conclude that the walk the dog action must be the result of a combination of effects as both the vortex theory and the momentum theory are working in the same direction.
Reading back to the numbered points made by Riverman (page 2), points 2, 4 & 5 all basically refer to the same feature, there must be significant width at the front. This is required to forcefully part the water and initiate the vortex shedding.
Point 1 increases the momentum for the walk the dog and point 6 would resist movement like trying to push a flat plate through the water. These two points would appear to contradict each other, but the rear mass creates momentum, once created, it takes force to stop it. A bit like pushing a truck, once it is moving it only takes a fraction of the energy to keep it moving. A fat rear end would provide that resistive force and dampen the action. I have always found that a fat rear end dampens my action!
Point 3 is interesting. Vortices have a minimum speed of about 0.5 meters per second. Any slower than this and laminar flow occurs and the lure travels in a straight line. A longer lure would be heavier than a shorter lure, thus it has more forward momentum and would thus glide further.
Posted 16 July 2007 - 06:58 PM
The swim baits are interesting beasts. I think the key other than proper weighting ( up / down) is the type of pivot that is used. I believe that a very free swinging pivot makes the job alot easier.
I keep thinking to try one with a thru cable and bead system but something tells me that it would be to rigid. Thus a stiffer action similiar to a glider.
Many people have used door hinges and the standard interlocking screw eyes. They seem to work the best. Even an interlocking wood joint and a thru nail. It worked great also.
I keep thinking that there is a way to tighten the links between segments for a more realistic look but that is a hard nut to crack with the wood body's
The mystery of the swim bait lives on! LOL
Jed your bait has really nice action!
Posted 16 July 2007 - 08:03 PM
have been using a hinge for my jointed baits that works very well, but i'm expiermenting with a new multi-jointed bait with string epoxied through the body segments, very flexible and a lot faster to install than a bunch of metal hinges. oh, before you all jump on me about material fatigue, it's Kevlar string, should hold up pretty good.
Posted 16 July 2007 - 08:30 PM
JR, did you find any problem with the epoxy travelling along the string, a bit like capillary action. I found that it soaked along the thread a couple of millimeters. Not a big deal, I just needed to compensate the application.
I made some five segment baits hinged with a nylon thread. I cut a knotch in the top and bottom of each segment and epoxied the thread in the knotch. I held the thread in place by superglue prior to epoxy.
Although successful, I decided that it was too time consuming and fiddly and moved on to one piece lures.
Posted 16 July 2007 - 09:58 PM
no problem with capillary action. the line channel is through each section in line with the other sections. i'm making the lure from PVC so no problem with having to waterproof anything. i used just a spot of epoxy in the center of each section then epoxied the sections together. just tank tested the protype and runs with the head stable and the tail wags. its a floater and runs just a few inches under the water. think i'm on the right track, will see after the finish is on it. will let you know.
Posted 29 August 2007 - 04:45 PM
Wow, some GREAT reading in this thread guys! I've also made a number of jointed lipless swimbaits and have noticed that if my tails are warped (I make them from wood) even a little, it causes the bait to come in like a stick.
Mine are only jointed once in the middle then have a wooden tail attached with a screw eye and split ring.
I'm curious as to how best epoxy wooden swimbaits? I put all my baits on a rotating rack to ensure no runs in the epoxy. Problem is that it gets into the joints and is a pain to remove. How do you folks epoxy this type of bait?
Posted 29 August 2007 - 07:21 PM
I don't know how well it is going to work, but I am going to use twisted stainless eyebolts and anchor one side with epoxy permanently, the other side with a little woodglue, paint, then take the bait apart to epoxy so that I can get good coverage without gakking up the joints. I'll let ya know how it goes.