sidewinder resistance and sensitivity

Another thread on resistance vs sensitivity has got me thinking...

Suppose I'm feeder fishing with a quivertip, there's no tow, I have a straight line (braid so we can ignore stretch) from tip, and the tip is about 90 degrees to the line. If a fish takes the bait and moves away from the rod 1cm then this will cause 1cm of movement on the tip.

Now imagine the same setup but with the rod pointing directly at the feeder (zero angle at the tip) and a sidewinder style indicator attached between the bottom two butt rings. Again a fish takes the bait and moves away from the rod 1cm. How many cm movement will this cause at the sidewinder? The answer is it depends. A sidewinder holds the line _away_ from the rod and the shape of the triangle formed determines the number of cm's movement. Viz it depends on

1) how far apart the two rings are

2) how near the middle of the two rings the sidewinder eye is

3) how far from the rod the sidewinder eye already is.

You can use pythogoras's theorem to work it out: if 1) is 80cm and 2) is exactly in the middle and 3) is 20cm then 1cm pull by the fish creates just over 2cm of sidewinder movement. And if 3) is 6cm then 1cm of pull by the fish gives an amazing 6cm of movement at the sidewinder! If you move the sidewinder eye further and further from the rod you get to a point where 1cm of pull by the fish will equate to 1cm of sidewinder movement. If you then move the sidewinder eye further away still (assuming it's long enough) you get _less_ than 1cm sidewinder movement for 1cm fish pull. Sensitivity on a sidewinder is variable!

Clearly the closer the sidewinder eye is to the rod the greater the sensitivity but the greater the resistance (since the sidewinder is bent more and is pulling back more). What I'm struggling to figure out is how the resistance for the sidewinder compares to the resistance for the quivertip. In short, does the different way the sidewinder works mean it can be more sensitive than a quivertip for the same resistance?

It depends how much of an angle you have it set at. The side winder's top ringmay be 3cm from the line between the butt rings but could be shaped like a horseshoe because the winder's anchor is closer to the mid way point. Or if the anchor is set further away then the shape of the winder will be a gentle arc. And various angles in between.

The beauty of the side winder is that you decide how sensitive you need it and set it accordingly.

Another point (and this is nothing to do with sensitivity or actual amount of movement, but the perception of it) is that the movement on the sidewinder will look like a bigger movement due to it being closer and because of the angle at which you're looking at it. So although the sidewinder may give a smaller movement the perception of it may be much better for the angler.

That's a good point Scott. But doesn't this just gives you an alternative way to get the same effect? Viz suppose I have a stiff sidewinder set with a gentle arc and it moves the line Xcm from the rod. If I have a 2nd much softer sidewinder set with a big horseshoe shaped bend and it also moves the line Xcm from the rod then aren't both sidewinders exerting the same force on the line? Viz it won't be affecting the sensitivity...?

Graham. Nice one. Hadn't considered that.

Still trying to understand if the sidewinder can be more sensitive than a quivertip for the same resistance...

if it is worth catching, you should know when it bites, haha/forum/smilies/wink_smiley.gif

that was quite in-depth thinking about indication jon.

I asked a clever friend - he thinks the answer is yes - a sidewinder can be more sensitive than a quivertip for the same resistance....

Suppose a fish performs an amount of work W by exerting a force F as it pulls the line 1cm (work = force x distance). At best this will move a quivertip 1cm. On a sidewinder setup, if a fish exerts the _same_ force F, as it pulls the _same_ distance 1cm, in the _same_ amount of time, then it performs the _same_ amount of work. The difference with a sidewinder is simply that you can choose (within limits) the amount of movement this translates to on the sidewinder by choosing the angle at the sidewinder. Less movement at the sidewinder means greater force at the sidewinder; more movement at the sidewinder means less force at the sidewinder. This matches experience too - to move the sidewinder a small distance from the rod (where you get a lot of movement) requires less force than moving it a larger distance from the rod (where you get less movement).This suggests you should fish with the sidewinder eye closer to the rod rather than further away from the rod...

I think you are over complicating things Jon, the sidewinder is more sensitive than a quivertip, by how much doesn't really matter does it? If you don't put tension on then it is even more sensitive but won't register drop backs, if you put just a little tension on it will register both.

I am only trying to find one thing out. Namely, if a given pull by a fish causes greater movement in the sidewinder than in the quivertip then has the fish necessarily had to pull harder? If the answer is yes then you have to ask whether it's a price worth paying. But as I say, I do not think this is the case. The sidewinder is more sensitive and there is no price to pay!

Then in short, IMO Yes.

Why speculate when its easy to try it out for yourself with a quivertip rod and a sidewinder.

My money would be on the sidewinder, like any butt mounted indicator, needing more force to generate the same movementas its tip mounted equivalent due to friction caused by the line passing through the eyes.

As usual I have got things the wrong way round. Sorry. My clever friend assures me his explanation of work = force x distance was to try to convince me that the resistance the fish feels DOES increase as the amount of sidewinder movement increases. He says that if the sidewinder pulls with a force of 1 (I think he said the units were newtons) and 1cm of pull by a fish equates to, say, 4cm of movement at the sidewinder then the work at the sidewinder will be 1x4 == 4. So the work done by the fish will also be 4. But since the fish has only moved 1cm the force it will have to exert will be 4. Shame.


Great advice Andy. Been away working. Home now. Will do some experiments in the garden tomorrow.