It seems like a question only I might ponder 🤔
Especially in a sideways world 🌎
With the equation of the depth C. and the line diameter being a constant, will adding weight A be the equivalent of the sum of A & B if the desired B weight was needed to be a larger number?
As a parody stated in the earlier paragraph?
I'm only focusing on keeping the jig down in this question and not jig action and more ideals.
Seems that water flow resistance and mass may be greater at first thought 💭, Butt keeping the bow out of the line is my first thought. (12 is greater than 8). How much does the water drag around both A and B when compared to a similar size G (which is the sum of A and B). Just wondering 🤔🎣
Hahaha, I don't fish like that and I am not a scientist so don't really know.
Just instinctively some thoughts;
A will probably not exert the same amount of downward pull (I think that will be weight) on the line as it would when hanging straight down. Caused by some lift created from current or the position of B
Two lures of combined weight equal to one single may have a greater surface area and more susceptible to the effects of the current?
The density of the material used will have a significant effect on this, like 5 flat pieces of stainless steel of equal weigh to one pure lead weight will have a much greater current effect.
Is lure B actually sitting on the bottom? It may then act like an anchor, or reduce the combined weight of the two lures.
I think the effect of the current on the line may well be greater then the effect of the current on the lure(s) obviously depending on the lengths, diameter and type of line.
I am sure our resident scientist will comment ??? ???::)
I think there are just too many variables in this question. Sometime we fish using the boats fish finder and can see the target is at say 60 meters below the boat. It then becomes important to change to a heavier jig to get it down to the fish as soon as possible but you quickly notice that the lure rate of decent slows down as it goes deeper.
I am trying not to take the bait, but cannot help myself :) My science fanboy opinion:
The problem with answering the OP question as formulated is that it makes it a bit difficult to get to the answer I think we are looking for. Jigs will generally not drop straight. They should have some sort of action, and the action will vary based on line tension. You have to look at the action in addition to the density and the resistance as the jig drops. Jigs not having identical sink rates and synchronized actions will also fight each other, further slowing the drop rate. I would expect that if both are reasonably close in drop rate and dropping action, the freefall drop rate might end up slower than the fastest dropping jig, and possibly slower than the slowest dropping jig in the pair.
Getting back to the question as posted: Unlike sliding friction (like in a reel drag) where surface area does not matter, friction is a fluid is a function of surface area. More surface area for the same amount of mass by using two jigs with the same combined weight as one big jig starts you out on the wrong track. But the more line that you let out, the more of the friction is along and across the line, and line friction will eventually become the biggest issue. Thinner line is the key for deep drops.
Cornelius is on the money IMHO. Tying multiple jigs in a series is just a faster way to lose more jigs faster while screwing up the action.
There are so many things that will most likely go wrong that the chances of things going right are pretty limited. For example, assuming the mess reaches bottom. you will be fighting against the resistance to lift the top jig before anything will happen on the bottom jig. A good way to go if you don't like much jig action and enjoy getting snags...
Ya neverknow, but I would take a pass.
just my opinion.
-J
I didn't understand the question nor the answer. Then again I get numbers mixed up all the time. :D ;D Dominick
I'd just use common sense, trial and error to figure that sort of stuff out, and document it for later reference. The heck with equations, calculations and science, they all give me a headache. ;) :D
Somebody is going to get a hook in their arm.
Thanks for your replies, I know it's a less than ideal question. ???
Sometimes the inquiring mind is a terrible thing said Wilburs mother to Orville. :'(
First:
Thank you J for not letting me down, I had every faith that you would have to respond and you did not let me down.
Second:
Although I've never seen it with these specific jigs, there are lots and lots of fish caught on in line jigs. I'm not certain why we don't think this will work?
The Man
Quote from: Ron Jones on December 21, 2021, 11:12:17 PM
First:
Thank you J for not letting me down, I had every faith that you would have to respond and you did not let me down.
Second:
Although I've never seen it with these specific jigs, there are lots and lots of fish caught on in line jigs. I'm not certain why we don't think this will work?
The Man
Glad you are entertained. In addition to being a science fanboy, jig design has been a hobby of mine for awhile now. This was right in my wheelhouse.
The original question was about how the combo would sink, not how well it would fish if/when it made it to depth.
To reiterate on the sinking part, the top jig will help by pulling against line friction on the/sink, but it will hurt when it flutters, darts sideways etc., as it will be sinking slower than the top jig and providing resistance of its own. Here is a thought experiment: if you tied the jig to a lead core or weighted line, the jig would not sink any faster unless the lead core got below the jig and pulled it down.
Getting back to your question of whether the combo would fish better once it got down there: the top jig is going to add resistance that works against your attempts to lift the bottom jig. On the drop, the top jig will arrest the dropping momentum of the bottom jig at various strengths and various intervals. It is possible that this would make some kind of magic action on the bottom jig that the fish find irresistible (more likely on the drop than on the lift) but you are mostly suppressing the a full action of the bottom jig. The fish get the deciding vote, but I would vote no.
I am assuming that we don't want the top jig to get bit, as it would be hookless. So the risk of getting bit on the top jig is a downside as well.
I agree that there are times when a tandem setup can work better than a fishing a single lure. For vertical jigging, you need a heavy jig and a much lighter lure (like a fly) hung above on a short leader. This will minimize tangles and not interfere much with the jig sink rate or action. That is why a jig and a shrimp fly is such a common tandem setup for vertical jigging. But you can actually tie some pretty big flies and get away with it. I have used the big fly technique to go for doubles on the lingcod when I though that I wouldn't be able to get many productive drifts that day. It worked a couple of times, but not enough to know whether a plain old shrimp fly would have worked just as well.
In summary, the best thing to do when the guy next to you on the rail ties on a rig with two weighted lures is to move as far away as possible. Whatever you do, don't encourage them.
As Wilbur said to Orville, "I'll let you try this first". :)
-J
Thanks for you civil comments and truth serum , this was not the greatest example of my experiments, it was a hypothitical situation of some everyday folks. I have been the scape goat here many times to not only learn things, butt to help others here that might read our comments and learn as well...... Everybody is different in abilitys, experience, monitary advantage, and time to make their dececions to hopefully fish as this is kinda a fishing forum, Ive learned a lot from this forum and can only thank Alan again for inviting me in.....
Thanks for your replys, Pease to owl world . :'(
I didn't realize that the top jig was hookless and tied in line. If it was hung on a loop I bet it would get bit, but as J says probably not enough for you to tell if is better or not.
Most important part of this reply: Wilbur was a wimp, DON'T BE A WILBUR!!! :)
The Man
Hey Gary,
I thought it was an interesting and worthwhile question. I was pretty sure that it did not work from seeing tangles, but never thought about specifically why until you brought up the subject.
Quote from: Ron Jones on December 23, 2021, 01:11:35 AM
Most important part of this reply: Wilbur was a wimp, DON'T BE A WILBUR!!! :)
On the other hand, don't forget that saying about the early bird getting the worm, but the second mouse getting the cheese. I wonder if they flipped a coin, or if Orville was more of the "hold my beer" type.
-J
I started off by laughing at myself for trying to answer something about which I actually had no experience or knowledge or did not even understand.
I am sure many a time some will think "duh,......what's he on about" but I don't mind that, after all it takes all kinds to make up a forum and we do need a good laugh from time to time. :) :) :)
I could be way off-base here but I'm about 80% sure these jigs are used as glorified sinkers, I don't think there's a whole lot of jigging that goes on. Just add more lead.
Thanks for your reply. Maybe I should have asked the question differently.....
Plane and simply. Wood adding a little more weight as shown in the diagram, help, and almost be equal to helping the bottom jig stay down?
It's a pretty easy question, Butt maybe out of the box 📦?🤷♂️
Thanks for your interest, time is short. Drop back down.😁
It's complicated. But largely, yes. Until the lower jig actually hit the bottom, at which point I guess it has done its job anyway?
But using a jig for the top weight is probably inefficient as compared to just using a large oval or pyramid lead weight, unless you want the attractant factor of the jig. Jigs have to have some shape to them so they have "action", a lead weight is generally the most hydrodynamic shape that will still achieve the end goal.
EDIT: I'm loosely assuming you're fishing reasonably deep water here as well, around 250ft+. Let's throw a bit of maths at it...
If we make the (flawed) assumption that braid is more or less round, and ignore the profile/surface area of it and focus solely on the cross-sectional area (I'm going to call this the vertically aligned "slice") that faces the tide...
For argument's sake, I'll use the example of 0.35mm braid (roughly 80lb in modern braid) and we'll say there's 100m (100000mm) of it in the water (I'm going to chop and change between metric and imperial a bit here, sue me).
That's an area of 35000 square mm for the tide to act against, or 350 square cm, or about 0.38sq.ft in the old money.... or a really, really big jig that weighs almost nothing.
Some of my stoutest jigs have a cross-sectional area of maybe 20 square cm but are only 10oz. As compared to a boring old lead weight which is roughly twice as heavy for the same cross-sectional area...
Also worth noting that when the tide gets going, streamlining all parts of your terminal rig help you to stay in contact with the bottom - long, thin baits, and minimising decorations that add drag such as squid skirts etc.
Anecdotally, I've seen a roughly linear relationship between braid diameter and the amount of weight required to stay in touch with the bottom. I've fished two rods on either side of the boat and the one with 50% thicker braid requires more or less 50% more weight to stay on the bottom, funny that...
Quote from: gstours on January 12, 2022, 04:08:22 AM
Thanks for your reply. Maybe I should have asked the question differently.....
Plane and simply. Wood adding a little more weight as shown in the diagram, help, and almost be equal to helping the bottom jig stay down?
It's a pretty easy question, Butt maybe out of the box 📦?🤷♂️
Thanks for your interest, time is short. Drop back down.😁
You guys keep changing the question. :)
The original question was relative effectiveness of two jigs vs. one for not getting bow in the line. The answer was (and still is IMHO) that the biggest problem is going to be on the original drop as the actions of the jigs cause the descent of each to to slow and speed up independently, causing the top jig to intermittently slow the bottom jig's descent. This was discussed in more detail earlier in the thread, so I will not repeat here.
I suspect that the mass to surface area of the two similarly shaped jigs vs. just one larger jig will not be the controlling factor. The ratio should be similar anyways, although there is a hydrodynamic advantage for larger shapes.
But NOW if we are talking ONLY about holding near bottom, the jigs will not be fighting each other as much, and now the main question will be differences in mass to surface area, which I previously claimed should not be consequential.
Now we are getting into fluid dynamics which is crazy complicated, but to my totally untrained simple brain, I think it works something like this:
Boon makes a good point about friction on the line, but estimating it well enough to get something useful gets way more complicated. On the drop in zero current, the friction is along the entire surface area of the line (friction in a fluid is a function of surface area). If you have ever towed some unweighted line behind a moving boat, you will have seen this effect of (longitudinal?) friction, and it can be substantial.
But after the drop in zero current, there is no movement of the line, and therefore no friction. Add a simple continuous (same from surface to bottom) horizontal current to the hypothetical simplest case of the line being perfectly round and straight from rod tip to jig) we now have fluid across a cylinder. But even friction across a cylinder is a complicated function involving viscosity, laminar flow, surface texture, blah blah, blah. If you are interested if you search on Reynold's number and friction, there are lots of online resources. But to get something accurate, I would suspect that this has to be modeled in software, or examined live in a wind tunnel or tow tank.
In real life, once the jig is descending or stopped, the jig will be affected from the friction both along and across the line. And the currents (yes more than one) can be moving in multiple directions ( north, east, south, west, up, down) in multiple speeds throughout the water column.
This is a long winded way of saying that the surface area of a slab jig cannot be compared with with the surface area of the line attached to it when it comes to comparing the effect of each on the drop or holding bottom.
While I disagree on using a comparison of relative surface areas, I do agree that line friction is the most important component when it comes to dropping and staying in touch with a jig in a current and at depth. I like to make fun of the new wave vertical jigging acolytes (cultists :P ), but they are right on the money when it comes to using the thinnest diameter line practical.
Whatever the actual line friction and lifting force turns out to be, you will probably cut it roughly in half if you can fish line of half the diameter. We non acolytes all seem to all use 65 to 80 lb braid where we used to use 30 lb mono for vertical jigging. Why not use 30 lb braid plus maybe a bit of chafing leader?
Just for fun, I checked Boon's math. At 0.35 mm diameter and 100 m length, I got a cylinder surface area of 1178 cm
2 , about 1.27 ft
2. I regularly get the math wrong, but I got the same number plugged into a couple online calculators. That is a an impressive amount of surface area.... I am curious as to what portion of the surface area Boon is using in his calcs, or if I just got some basic math wrong again :)
-J
I didn't use the surface area of the braid as facing the current (half the circumference), just the "silhouette" as it were of the braid, as if it were a flat plane. So literally just the diameter - hence the different maths. I figured it got almighty complex if you used the surface area, because the varying "angle of attack" would mean considerably different drag figures across the "face" of the braid. And then you presumably get some sort of eddy effect behind the braid (like a golf ball) that reduces the effective overall cross-section... or if the flow curves outward, you would get an exaggerated effect... it all makes the head swim, although I'm sure with the right software you could probably model all of it. I just wanted a sort of relative idea of the cross-sectional area facing the tide.
Long story short, a second jig (setting aside fluttering action etc) would help to reduce line angle/stay in contact with the bottom, although probably less efficiently than a single larger jig, however if you don't need the abrasion resistance (aka you're not fishing on a party boat) then lighter braid on a lighter rod and reel with a lighter jig is all in all more enjoyable to fish with.
Also the cult of the vertical jigger is going to hunt you down and teach you the ways of Yoichi Mogi :D :D
Thanks everyone again for sharing your information and thoughts 💭. When this topic was about ready to post, It was apparent that the wording needed to be spacific about holding bottom. Maybe the title science and friction?🤔
Both of you have done well to school us on what's going on down there.
I've already switched from 80 to 65# for my heavy jig setup. And 50# for the medium.
You have convinced me that even lighter is in order, It's going to be more fun and I,m in for that.
Thanks again. Gs.
Quote from: boon on January 13, 2022, 01:31:26 AM
I didn't use the surface area of the braid as facing the current (half the circumference), just the "silhouette" as it were of the braid, as if it were a flat plane. So literally just the diameter - hence the different maths. I figured it got almighty complex if you used the surface area, because the varying "angle of attack" would mean considerably different drag figures across the "face" of the braid. And then you presumably get some sort of eddy effect behind the braid (like a golf ball) that reduces the effective overall cross-section... or if the flow curves outward, you would get an exaggerated effect... it all makes the head swim, although I'm sure with the right software you could probably model all of it. I just wanted a sort of relative idea of the cross-sectional area facing the tide.
Gotcha. A cross section along the length of the line. Don't know how well this pans out as a rough estimate, but I guess that your point is that there is a lot of fluid friction on the line, which I totally agree with. It is just the science nerd in me that needs to drill down a bit deeper. Sorry. It is my nature.
I think that what you are describing with the eddies is the vortex stream. And then there is laminar flow where the some of the fluid sticks a bit and and follows the surface around the object inward, past the widest point, which contributes to the vortex stream. Fascinating stuff.
But don't discount the simple friction involved along the entire line surface. For example, if you lift the rod tip two feet in 1/8 second, if the jig actually moves that much, it would be moving an average of 11 MPH. Tow 100 meters of of braid + leader (no jig) behind the boat at 11 MPH, and you will get an idea of the amount a friction along the line that is happening when you are trying to lift a jig in perfect conditions. This is in addition to the effect of current or jig. Now if you tie your jig on and tow at 11 MPH, you might lose faith in the need for finely tuned jigging rods, but I will save that for another thread.
Quote
Also the cult of the vertical jigger is going to hunt you down and teach you the ways of Yoichi Mogi :D :D
Beware of getting what you ask for. A loss of faith in the face of harsh reality can be kind of a bummer to witness, especially for the acolytes. It could turn out like the walrus and carpenter scene in "Dogma" :)
-J
Quote from: jurelometer on January 13, 2022, 06:06:10 AM
Quote
Also the cult of the vertical jigger is going to hunt you down and teach you the ways of Yoichi Mogi :D :D
Beware of getting what you ask for. A loss of faith in the face of harsh reality can be kind of a bummer to witness, especially for the acolytes. It could turn out like the walrus and carpenter scene in "Dogma" :)
-J
We should start another thread for this, but I did some not-terribly-scientific testing on the weekend with a 100g jig, PE3 line and 230ft of salty water and it largely agreed with the cult's version of events, do I need to go deeper?
Deeper? That's why I never ask? ??? There's a lot more we can learn while we are waiting for the problems of the reel world to heal over.
Like in the original post, what happens down there when you drop a jig? Crazy stuff.
Last year I asked a question, kinda, like does the weights , circumference and shape matter much? Or is the line drag/ bow the main or only thing that keeps the jig down?
Let's go on to add , On contact with the bottom.... In the mid water you really don't have a way to know, Except maybe sonar or ?
In my fishery there is almost always a current. Quite unlike what a lot of the mid equater folks call norm.
I'm glad some comments are keeping us in a helpful mode. The next post will start a new question.🎣
The shape... is an interesting beast. In terms of both falling and staying. It makes an enormous difference in the falling/sinking of the jig, a tail-weighted jig will sink more or less directly whereas a mid- or top-weighted one will flutter and dart and sink much slower.
Once it's down though... in terms of not angling out with the current? To a small extent it will relate to the shape of the jig, but I honestly think the prime factors at that point are the weight of it and the diameter of your line.
✅ ok, there might be some more parts to the equation that have not yet been discussed. With everything being constant for this equation, When the line angle changes from vertical to flat (parallel with the bottom) I,m thinking 🤔 that the line area has greatly reduced its drag (water friction?) and the weight (lure) will be more able to stay on the ocean floor.
Let's talk about this question, considering what was discussed earlier as does gravity have more to do with the weight as the line flatter may have lessened its ability to lift the jig/weight?🤷♂️
Think of holding a plank in a river. If you have the plank parallel to the current, the force on the plank is low; it is only the friction of the water against the surface of the plank. If you force the plank into an upright position, the force is hugely increased; you now have the hydrodynamic drag of the water having to go around the plank.
Quote from: gstours on January 18, 2022, 12:37:50 AM
✅ ok, there might be some more parts to the equation that have not yet been discussed. With everything being constant for this equation, When the line angle changes from vertical to flat (parallel with the bottom) I,m thinking 🤔 that the line area has greatly reduced its drag (water friction?) and the weight (lure) will be more able to stay on the ocean floor.
Let's talk about this question, considering what was discussed earlier as does gravity have more to do with the weight as the line flatter may have lessened its ability to lift the jig/weight?🤷♂️
What you are getting into now is the whole enchilada of the physics of jigging which is a combination of gravity and fluid dynamics. The answer is a bit long, and nobody reads long posts on the internet :)
So let's just get our toes wet for now.
Assuming the jig is off the bottom, not being dropped or lifted, and tied to a line going up to an anchored boat:
1. Gravity is pulling the jig downward.
2. The current is moving against, and then around the jig. causing a low pressure zone on the back side, so the jig will be pulled/pushed toward the low pressure. The amount of force from the current on the jig will vary as the jig twists back and forth. Jigs are usually designed to be unstable. That is what gives jigs a wobble. If the jig can swing and lay out flat it will have the least resistance, so without the effect of gravity this is what would happen, like Boon's plank example.
There will be a couple points of equilibrium between gravity and the force of current that will determine the orientations of the jig as it wobbles.
3. The same thing happens with the line, but the line is light, round and flexible. Gravity will have much less effect than any decent current, and instability will be minor. Without the jig, the end of line would end up almost parallel to the current. If the current is strong and all the way to the surface, the whole line might end up laying out flat just beneath the surface.
4. So what we have in combination, is the effect of gravity on the jig pulling both the line and jig down, duking it out with the combined effects of current pushing both presumably horizontally. Somewhere in between straight up and down, and laying out flat, equilibrium is achieved.
5. If you are fishing 150 feet plus depths in strong currents like you would see in the Pacific Northwest, line diameter is really key, as at that depth, diameter is going to have a major effect. The smaller the line diameter, the lighter the weight and the stronger the current you will be able to fish.
6. Now since most jigs are designed to be unstable when moving though water, as the jig wobbles, the equilibrium between the effect of gravity vs. current will change and the jig will drop into a more vertical orientation and rise into a more horizontal orientation, sort of bouncing between several different points of equilibrium. This is why some jigs get bit well when fishing deep in a strong current. At enough depth and current, your jigging action at the surface is not adding enough force into the equation to change the movement much. But some jig designs will still be using the line tension, gravity and current to do the work for you. Or mebbe some combo between your jigging action, and what the jig is doing without you.
7. On the initial drop, and later as you attempt to move the jig up or down, things get more complicated, and we have to start adding in the effect of jig action, friction along the line (as discussed earlier in this thread), and the compound effects of multiple elastic components (the rod and the line both behaving like springs), further enhanced by the spring-like effect from any bow in the line, plus what happens on the long drop if the current catches your line and adds in a "reverse" bow. But nobody is reading this far in, so I am going to stop typing :)
-J
Thanks everyone for their added comments to this crazy post. Some one even said " this science stuff makes their head hurt ". I,m hear to learn and will let you do the math.💻
In my experience with fishing bait with a weight from an anchored boat the depth has a lot to do with the amount needed to stay in contact with the bottom.
Secondly I,m sort of new to jigging, and my fishery is solely a bottom thing, not mid water. Bottom contact is very important.
So for this let's leave jigging out of the question.
Thirdly, we have large tides compared to most places and at times the same location is "unfishable".
Most of the time the water velocity is changing, so misjudgment can be costly in time , wasted energy, and possibly gear.
Lead weight ( cannon ball type only for this question) has no real action unlike the jig discussed earlier, So if a weight (wa) is too light to hold bottom sufficiently, and another weight, this time 2 weights (wa+wb) added a few it
does seem sufficient, Does the increase in weight and area (2 diameters) of the pair of weights cause more drag, water friction, than if one only weight (wc) was used? Weight (wc) being the sum in ounces of wa+ wb =wc. .?
If this question is not worded correctly, my thoughts are that like in sectional density, a co efficient could be assigned to find a n answer? We can easily give the spheres a,b,and c a value, Butt that's where I'm dead in the water......🤦♀️
I've been under the superstition that using one large weight is more effective in the above hypothesis.
As it's " possibly more efficient " ? Just wondering?🎣
Basic geometry really.
The weight (mass, really) is a function of volume.
The hydrodynamic drag, all things being equal, is a function of surface area.
If we're working with a spherical weight...
Volume = 4/3(pi*r^3)
Surface = 4(pi*r^2)
For a volume of 1, r = 0.62, giving a surface of ~4.84
Doubling the volume gives r = 0.78 and surface ~7.68
Because 4.84*2 is larger than 7.68, we can confidently say it is more efficient in terms of drag to use one large weight than two smaller ones.
1. If you are holding bottom, the shape of the weights buried in the sand won't matter much. Even if resting on a hard bottom, the friction on the line is going to eclipse any difference in the hydrodynamics of the sinker.
2. When dropping, you want the best hydrodynamics for a given amount of mass - generally surface area, but also shape. One torpedo or teardrop = best, five lead frisbees with a hole in the middle = worst.
3. If the payload consists of three salmon heads, a whole humboldt squid and a side of beef, the shape of your sinkers, and how many you use is the least of your hydrodynamic problems.
Hey Boon,
I think that Gary might be not be vertical jigging. He may be trolling, and we are taking the bait :). Every time we answer the question, the question changes. ;D
-j
A window sash would work best. Actually that is a joke; who would want to reel up a window sash. I think using down riggers at anchor would work best. Let the downrigger weight touch bottom then come up a few inches so it does not bounce. I think it is worth a try. Dominick
✅ ok, just when it may have been suggested, no one reads these scientific long winded answers?....
My fishery is different. The math answers this last question. There's going to be more.....
At first I thought it was an easy answer...... butt like a good mentor might say, It's how you ask the question.
Thanks for sharing, 🎣. And helping all of us to learn some things mabee no one's going to ever ask us the question of.....🤷♂️
Quote from: Dominick on January 19, 2022, 11:41:38 PM
A window sash would work best. Actually that is a joke; who would want to reel up a window sash. I think using down riggers at anchor would work best. Let the downrigger weight touch bottom then come up a few inches so it does not bounce. I think it is worth a try. Dominick
I know of people using cast iron sash weights for deep dropping to Swordfish in 1600ft+ - but they break the weight off once they're at target depth, with just a relatively small (24oz say) weight to keep it there.