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Posted 18 February 2007 - 10:33 PM
OK..I am coming out of the closet. Yes, I have a problem! Upon my old post searches it seems like wiggle,wobble,etc, are used to define everything going on behind the bill? So I would like help with terminology. Having looked down on a crankbait my whole life I can see the action between the Head and Tail and somewhat understand it. What words can apply to this action? I am more curious in the action that I can feel but can't see. The action between the Back and Belly. What terms would apply to this action? I can allmost understand this. But my Peon Brain can not put both of them together! What are some things I could look at to change the action between the back and the belly? With the baits that I have built it is either there or not. So I obviously still do not understand what I am doing to cause it. Thanks for the cool site!
P.S....I was going to hang it up and then I stumbled on this site and saw Maddox Bays Divers...Awesome!
Posted 19 February 2007 - 02:41 AM
I to am a newbie at crank bait making and am curious about the action you mentioned between the back and belly. I didn't know it existed.
Posted 19 February 2007 - 03:23 AM
Their are three movements available to the lure designer, as in aircraft design and submarines. These movements are called yaw, roll and pitch.
Like you, I am totally confused by the terminology used on this site. I am convinced that people are referring to diferent interpretations. A standard needs laying down, but why create a new standard when the world outside lure building has got it covered already. Here follows industries definitions and what I think the tu word is (but could be wrong on the latter).
x axis represents a horizontal line from nose to tail.
y axis represents a hirizontal line from side to side.
z axis represents a vertical line from bottom to top.
Yaw is rotation movement about the z axis. Looking down on the lure, it 'waggles' or 'wiggles' from side to side.
Roll is rotation about the x axis. Grip a pen between finger and thumb and roll it, this is 'roll'. TU members refer to this motion as wobble, but very often people use the word wobble when they actually mean waggle.
Pitch is rotation about the y axis. Looking at the side of the lure, holding the lure between finger and thumb at the centre, raise and lower the nose so that the lure rocks like a see saw, this is pitch. TU does not have a name for this motion, in fact I have never read a single word about it and yet it is a valid movement, easily achievable with the correct lip design.
As for what lip generates each shape, Horisontal lips produce near pure roll action. Vertical lips produce near pure yaw action. Lip angles between these two produce a combination of roll and yaw.
I hope this basic introduction to the movements helps. I would be interested to hear everyones interpretation on wiggle waggle and roll so we can all talk about the same thing without confusion.
Posted 19 February 2007 - 02:58 PM
Vodkaman, very interesting, about four months ago, I started trying to make crankbaits, I must have made 30 to 40 of them and all were scrapped because they were either unbalanced, wouldn't yaw or waggle or worse, some of them the whole lure just spun like a spinnerbait blade. A couple of the early ones ran straight but did what you refer to as pitch. I was pretty excited about it because I had never seen a crankbait do that before. I called it porpoising. It was very rythmic and made your rod tip pulse. I told one of my friends about it and he said to throw it away that it wouldn't catch anything. He said several years ago one of the bait companys had out a crank that did that and it just wouldn't catch fish.
So I trashed them too.
It took me almost four months make a crankbait that runs true and waggles correctly. It really cuts (waggles) a very nice X in the water and I can't wait to take it fishing to see if it will catch a (hopefully some ) bass. I am also trying to learn the art of airbrushing. I am getting better at it but nothing fancy like I see posted on TU. I went to the fishing expo here in Knoxville a few weeks ago and met JawJacker and saw his cranks up close. Beautiful Work!
I look forward to the day that I can paint and carve like him.
Anyway, thanks for all your posts I've learned a lot from them.
Posted 19 February 2007 - 03:01 PM
"z axis represents a vertical line from bottom to top."
Vodkaman where would the Z axis line be on a typ. crankbait? The line tie or the weight? What about double weight insertion points?
Posted 19 February 2007 - 04:51 PM
All the rotations are through a centre point which is the sum of all the loads affecting the lure. A major piece of this is the centre of mass of the lure and the ballast. Another is the centre of buoyancy. As you retrieve the lure, the line will also be trying to keep the lure central.
This last weekend, I built some lures with rear mounted ballast as I am working on the 'cast-ability' of my design. Looking down on my lure revealed all the above. The extreme rear mounted ballast caused the crank to yaw or waggle from the rear end, the reverse of what we are traditionally looking for. It was shaking its head quite dramatically, as the lure has a very wide yaw or 'waggle'. I was surprised that the line load did not limit the movement more, in fact the line effect was hardly noticeable. I digress, enough about my project, back to the point.
It is easy to accept that roll occurs about the x axis and quite easy to imagine the pitch or porpoise effect happening about the centre of the bait at the y axis, rather than at the line tie. But for some reason, the yaw action is much harder to accept. I think a lot of it is wishful thinking or hoping that it waggles about the line tie, we think that this would be more fish like.
A lot of discussion has gone on about ballast position and its effect and its importance, some of it quite heated or enthusiastic! The fact is that ballast plays many rolls in the action or movement of the lure. It determines whether the lure is a sinker or floater. If part of your fishing strategy is to pause the bait, the ballast position will determine how it sits in the water, if you want it to sit horizontally then it must be directly under the intersect of all three axes, roughly, the centre of gravity of the wood as this is also the centre of buoyancy. The distribution of the hardware will affect the location of this position.
If the ballast was placed at the axes centre, the lure would remain still in the position you placed it (in theory) as the lure no longer has information as to which way is up. My own, rear ballast casting lure points to the sky, that is my choice. At the end of the day, you have to decide what properties are important to you and design your lure accordingly, the hard part is getting it to do what you want it to do, rather than saying, ‘that’s nice, I like that’.
But no matter where you put the ballast, at one metre per second retrieval, it will have virtually no effect on the angle that the bait swims. The slower the retrieve the more the ballast plays. This is because the effect of the weight of the water on the working surfaces of the lure are far greater than the ballast. The distribution of surface area above and below the line angle is far more important. The sharp edges of the lip have a much more pronounced affect due to the strong vortices generated behind the lip, which create the action of the lure and totally destroy any ideas you might have of calculating the areas to reveal its secrets.
As for multiple ballast positions, if you split the ballast in two and move one forward, the other rearward equal amounts. The resulting centre of forces will still be in the same place but the action of the lure will be reduced. To demonstrate this, take a thin stick, attach two equal weight sinkers at the centre, grip it in your hand and twist your wrist back and forth. The stick moves easily with little resistance. Move the weights to the ends of the stick and repeat the experiment. The action is much harder to perform even though the balance point has not moved.
The explanation is inertia, the reluctance of the body to move. It is not just the amount or weight of the ballast, the distance from the centre of forces makes things worse. In calculations, it is called ‘taking moments’. The mass is multiplied by the distance to give a true representation of the load, balance or inertia. Surface area has a similar effect on the action of the lure and will be affected by the distance of the centre of the surface to the centre of forces. If you are looking for a wide yaw or waggle action then deep, flat sided lures are not the way to go, same applies to roll. Deep, flat sides would be a good shape for pitch or porpoise action.
Not every lure designer is looking for maximum action, most are looking for something a little more subtle. Personally, by searching for the maximum, I have learnt how it works and what effect each component of the lure has on the result. You could argue that my lure is more likely to scare the fish away rather than attract them, but rest assured, each lure will have its day. You can really get in to the science and mechanics of lures, for me it is the most enjoyable part of the design process. Are my lures any better for it?
The fish will be the ultimate judge.
Posted 19 February 2007 - 06:08 PM
That’s nice, I like that! Should be in a sticky thread for all to see and read, until the knowledge base is restored. Excellent!
Posted 19 February 2007 - 06:27 PM
is there something special about the place in which the axis meet?just wondering
Posted 19 February 2007 - 06:32 PM
On minnow type lures , I have found distribution of weight throughout the "keel"/bottom of the lure to be very effective. The lure that is properly "balanced" is often the one that I reach for first.
Posted 19 February 2007 - 07:07 PM
Posted 19 February 2007 - 09:43 PM
Thanks Everybody. I had not really paid attention to other movements until I started with a deep belly flat side design. And.. Yes I got what you are calling the X thing going on. It was the hardest thing to control that I had come upon. It may not be a fishcatcher but it is fun (Frustrating) to play around with. Now I have some other movements to look at I had not even thought of. The tweaking goes on! And since I said the action behind the bill...Is the bill doing the same thing the body is doing but in a much tighter fashion? I guess it is since it is attached to the body. Why have I not looked at it that way before? Thanks Vodkaman for waking up my brain!
Posted 20 February 2007 - 06:52 AM
Placing the weight in the keel or the lowest point of the body is my preferred choice. It gives good static or motionless stability as the centre of mass and the centre of buoyancy are kept as far apart vertically as possible, the lure will stay upright. This is also a good arrangement if you are looking for yaw action or 'waggle'. The ballast centre is lying on the z axis, therefore their is no moment distance to hinder the motion (re the stick experiment in my previous reply), the towing and water pressure forces prevent the waggle from becomming unstable. However, if you are looking for roll or wobble action, a low slung weight will reduce the wobble due to its offset distance from the wobble axis (x axis). If you move the weight up too far ie close or even in line with the x axis, the roll will become unstable and turn over.
Once the action or movement has started, their has to be a force to stop it or it will continue. In the case of yaw or waggle and pitch or porpoise, it is the pressure of water. In the case of roll, it is the vertical stability caused by the distance between the centre of buoyancy of the wood and the centre of gravity of the ballast.
Instability As with the ballast instability, for each type of movement (yaw, roll and pitch) their is a point of no return, an unstable condition. Unfortunately, if you are searching for a maximum effect, this occurs just before the unstable condition takes over. At this point, the lure no longer returns to centre but continues its movement and rotates about its particular axis, out of control. The point at which all these instabilities occur is at the centre of forces, where all the axes intersect.
Yaw and pitch instabilities are most unlikely ever to be experienced unless you position the line tie half way down the back. At which point the line tie would coincide with the z axis and the yaw or waggle would become unstable. The line tie would be at its closest to the y axis, therefore the pitch or porpoise effect would be at its maximum, close to instability.
Roll instability This is the biggest cause of lure failure. The lure spirals out of control. Some call it 'death roll' and to be brutally honest, I am still trying to get my head around it. Explanations have been posted but I have yet to be convinced of a good explanation. In keeping with the previously discussed instabilities which are easy to picture, including the ballast instability, then the roll instability must be tied in with the intersecting axes, the centre of forces.
Unfortunately, this majic point takes on a new life of its own once the lure is moving as more forces are acting on the lure, therefore its position moves accordingly. At this point the brain starts to hurt. By far the main force that changes everything is the weight of the water acting on the lures surfaces. Another force to join the mix is caused by curvature, the same type of force that allows a wing to lift a 747 off the ground and is not to be ignored.
So, after all the technical research, prototype experiments and discussions, I am no closer to predicting roll than when I started all of this, several months ago. But when I find a lure that rolls, I get a little excited, an opportunity to search for the explanation why. I would like to collect everyones 'rollers' and continue the search.
I would definately like to hear everyone elses opinion on roll over.
Posted 20 February 2007 - 06:02 PM
So...x-ing is half roll and half yaw? A Bagley B or square bill would be mainly yaw? I have taken the tail and moved it up above the x axis and it seems to have knocked alot of the roll off. Does that make sense? I was allready maxed on weight. I still may have to change the bill angle. Trying to tweak it so it runs at all speeds. I guess it is better to have too much roll and come down from there than to start with none at all. Thanks for the last post, that has the information I need. Maybe no anti-depressants tonight!
Posted 20 February 2007 - 06:24 PM
With a lure shape like that, it is dificult to know exactly where the x axis ran. If it had good roll before the mod and the roll reduced after, then the axis probably ran through the tail. This would be good design.
By raising the tail, you have pushed it 'into the wind' as far as roll is concerned. You have introduced a side load with a distance from the rotation axis and stifled the roll action (re-the stick and weights experiment). Unless I am misunderstanding your modification.
Posted 20 February 2007 - 06:29 PM
Where do you measure the z axis from?ehat points on the lure?
Posted 20 February 2007 - 09:38 PM
I think another part of the roll equation maybe the fact that a lure acts somewhat as an airfoil. The airfoil is "unbalanced" by the lip as you begin the retrieve, creating lift on side of the bait. When the lure begins it's motion to the right say, you need enough "lift" in the body of the lure to counteract this right motion and send it the other way. If the body does not have enough surface area, or the lip creates to much pressure, the lure will simply continue to spiral.
Posted 20 February 2007 - 11:05 PM
Vodkaman, I'm no physicist, but your explanations make some sense if you read carefully. In the near death roll I've seen, it was a combination of factors.....
1) Balsa wood....very bouyant, but used too little weight to offset the flat side design. If you throw a piece of wood into water, it will float flat side up.
2) Jointed bait....not really sure how much the jointed action made it different. But this was different from any I've seen.
3) What I call "obtuse" lip angle. The lip angle was near "vertical" on the Z axis. Basically near the angle of topwater, but slightly skewed out to dive angle. And the lip was too long for that design. Trapezoidal shape rounded at corners.
Bottom line, near death roll. This bait will swim normally at slow speed, and then kick on it's side and flounder on the top of the water at higher speed.
A failure by our standards, but just the kind of thing that might trigger a huge fish to strike.
Posted 07 July 2016 - 09:51 AM
Seems like the "y" & "z" axis should switch places as far as knowing which is which. Lol
I can't help but think of a coordinate plane with its horizontal & vertical number lines...thinking of an "x" axis (horizontal)immediately signals my brain to think that that the "y" axis should be perpendicular to the x axis.
Are these axis you listed defined by TU or is there an engineering background behind them Vman?