Line Comparison

[Gressak]

Fujino Straight Line, Moonlit Tachi, Spiderwire, Nissin PALS LL#3

The first three are multi strand and the last is flourocarbon.

A lot of concentration of lines is on weight, but I wonder if anyone has weighed these lines. The multi strand lines are thicker but they also have a bit of space and air between strands, where the flourocarbon has none.

The Fujino and spiderwire are about 25% thicker than the PALS LL#3 but is not 25% denser. Perhaps equal or even less than the PALS LL#3.

Just food for thought and yes I am being a devils advocate.

I have been fishing the 65# spiderwire invisibraid my last few outings. It is highly visible and casts very well. Normally I cast a 3.6 m line, but as an experiment, I fished a 4.5 m line on the river and it casts perfectly. Visible, No memory, and cheap…You can buy 125 yards of the stuff for 12 dollars at walmart.

[Peder]

Thanks for sharing @Gressak. Do you have a gram scale or some other scale that can measure really light weight? It would be interesting to see how much equal lengths of each line weigh.

What rod were you using with the 4.5m line?

[Gressak]

I do not own a scale. I agree it would be interesting.

Sato. Out of curiousity, I fished it at all three of the lengths. 330/360/390. It fished well at all three, which sort of surprised me. What also surprised me is that 4.5 m was not two awkward in the larger pool I was fishing. It has been a while since I have fished a longer line. Perhaps my casting skills have improved.

I have been curious on the 50# line weight. thinned diameter… I might try to find some to try.

There is something about these braided lines. When new, they are stiffer and more rigid. I think this a positive quality. When they break in the fibers spread out a little and the diameter enlarges slightly. It should be interesting to see how they perform long term, but from what I recall this particular line does not fray out as much as spectra lines do.

The interesting thing is this line is made from dyneema, which is used in camping, sailing, and outdoor sports…

http://www.coastalwindsports.com/WhoseLine.html

Dyneema (DCF) Technology + Hyperlite Mountain Gear

The thinner diameter, texture, and and density of the LL probably has less wind resistance on cast. How much is hard to say. The spiderwire and the Fujino are close to being smooth but not as smooth as the LL.

I might be a fool but I really cannot tell the difference between how these lines fish. I probably do adjust my casting stroke, but I do not feel that one line out performs the others by a considerable margin. There are tradoffs…

Fujino - excellent visibility, no memory, multi strand, medium density, smooth texture, low water absorbtion, two diameters, one color, predefined lengths - no recoil post snag

Moonlit Tachi - excellent visibility, no memory, multi strand, medium density, smooth texture, medium water absorbtion, wider diameter, multi colored, predefined lengths. -recoil post snag.

Spiderwire- excellent visibility, no memory, multi strand, medium density, smooth texture, low water absorbtion, reasonable diameter, single colored, variable lengths - no recoil post snag

LL - poor visibility , memory coils, single strand. high density, smooth texture, zero water absorption, range of sizes/weights, range of colors, variable lengths - no recoil post snag

I will take pics of all the different lines I own. I will get nylon and a bunch of moonlit lines I own in a lineup.

I really like the moonlit lines. The biggest negative is that they twist/knot up post snag. The diameter and water absorption can also be issues, but that can also be a feature. on windy days. Cost is also a factor. They are not cheap, but considering they are hand made, I think the price is very fair.

[dwalker (David Walker)]

Someone who reloads ammo would probably have a scale capable of weighting line weights of different types of lines.

I’ve misplaced my tenkara notebook that I’ve filled with information over the last few years. In it I had the line weight for a spectra furled line from Oleg’s Tenkara Times website. It is no longer there as far as I can tell.

It also I had some ballpark weights for FC lines.
Weights I had figured out from the information on the Yoz-ami website. Line information that was on their website before they updated the site a couple of years ago. It’s a shame they did away with that information.

Anyway, because measuring the diameter of small threads is difficult manufactures measure the line weights instead. Using either denier (x grams/ 9000 meters) or dtex (x grams/ 10000 meters). If the denier value is correct then the entire 9000 meter of line should have the same average diameter. Within manufacturing tolerances. Fortunately in a post I did on the TUSA forum four years ago (Understanding the Japanese 号数 line numbering system) I found some FC denier values from the Yoz-ami website:

1号 = 340 Denier, 2号 = 680 Denier & 4号 = 1360 Denier. So you can see a 2号 line weights 2x the weight of a 1号 line, and a 4号 line weights 4x the weight of a 1号 line.

The 1号 line is the reference value. But beyond that there is no real industry standard. It’s more or less up to companies honor to show they have excellent QC standards. And of course each line manufacturers’ line weights will be a little different, and each type of line from the same line manufacturer will vary a bit due to different materials used to make each formula of line, and just plain old manufacturing tolerances.

But those yoz-ami denier weights should give you a ball park estimate of FC line weights. Just use the denier value to calculate the weight of 3.6m or 4m line or whatever length you want to calculate the weight of. Probably even different sample lengths of line off the same spool of the same length will probably vary a little bit. Just remember that a 4号 line will be 1.333 x the weight of a 3号 line when comparing similar lines from the same manufacturer. At least in theory.

Dyneema from what I have read was originally developed by the Dutch for making commercial deep sea fishing nets. And later found it’s way into being used for sports equipment. I think Spectra line is about the same thing, just a different manufacture’s trade name for a very similar product.

But to compare the weights of different types of lines of the same length an accurate scale might be the only way to determine it. A gun powder scale might be close enough.

I am always amazed at how people figure out stuff. I recall reading a story about how an envelope addressed with ink was weighted, then they added a missing dot over one of the letters. Re-weighted the envelope and determined the weight of the dot of ink. However, bright guys like Amedeo Avogadro figured out a long time ago how to measure the number of very small things.

[dwalker (David Walker)]

Gressak, you might find this information provided by Kevin Kelleher (aka Softouch 333) interesting. He provides some gr. weights of a few different lines. Rigs floating T-line , RIO Running line, etc. And the TUSA 10.5 foot furled Kevlar line I have weighed 15.5 Grs.

http://tenkarausa.com/forum/viewtopic.php?f=4&t=4945&sid=0afe50a097149841220f5ce2da887cea#p30685

You might even contact him for more information. Depending on how deep your interest is. His curiosity about line weights of different lines might still be a topic holding his interest.

[Gressak]

Dang David…you are a beast.
Thanks for sharing…and although i am a half decade late to the party…its good to know i am not alone in my thoughts.

Rehashing hash.

As noted in that thread weight is only one factor in how a line fishes. So i am not driven much to dig into exact weights.

This thread was driven by the notes on the fujino lines and LL in other recent threads.

Sometimes working out this stuff in the forum really helps solidify choices when picking tools in the field.

[Peder]

EDIT: I’ve updated the images (and added more) to make more sense.

I think I would need seem hard evidence to necessarily agree with all of your analysis @Gressak. I do agree that if you increase the length of a line by 50%, that the weight of the line increases by said 50%. Where I’m not sure that I agree, is whether the drape (otsuri) necessarily increases by the same amount.

Here’s an interesting thought for a potential experiment, although one would need to have enough space to do it. I think it may be easier to explain it via bullet points (at least it is for me), so pardon me if this seems oversimplified and/or too long. For full disclosure (and the sake of expediency), I gratuitously took and embellished the following drawings from @Paul_Gaskell and Discover Tenkara from here and take no credit for creating the image, only bastardizing it.

1. This part may need help from a second person (unless you’re really creative). Take your rod of choice and hold it at the proverbial ideal of 90°.
   

   

2. Measure the vertical distance between rod tip and an estimated point where the surface of the water would be. (See image.)
   

   

3. Next, measure from rod tip to where fly/kebari would touch the water for your given line length. (See image.)

4. Now you have the math to determine your triangle (should you want). Next part will be a little more difficult unless you have the space.

5. On a wall, mark the spots you just measured with a small nail or thumb tack or something similar.

6. Take 3 or 4 (or some number of your choosing) of different types of lines. Just make sure they are all the same length.

7. Tie one end of each line to the nail or thumb tack that represents the tip of your rod.

8. Tie the opposite end of each line to the nail or thumb tack that represents the surface of the water.

9. Repeat the whole process with a different length of line and tack it up close to the first set you did.

I could be out of my mind here, but I think it could be an informal way to test the drape of different lines under identical circumstances aside from their length. For example you could take 3.5m of fluorocarbon LL, a furled line, some braided mono, some nylon LL, and a tapered line. Right next to it, you could take all of the same lines but at 4.5m (if you have that many lines) and put them up with your new measurements.

If you wanted to get more technical, you could draw a line on the wall between the two tacks that represent the tip of your rod and surface of the water. Then from that line, you could measure the depth of the otsuri for each line. Though, this would be slightly complicated by the fact (this is a presumption) that the otsuri drape profile of each line will fall at different points. We could quickly get into some more complicated math and some geometry if we really want to.

I have no idea if this even makes sense to anyone outside of my own head and I have not tried it myself, but it seems like an interesting experiment to me.

Thoughts? Ideas? Suggestions?

[Gressak]

The reason for the drape is not just a factor of weight…no matter the line. It is also presentation angle.

Consider your rod the hypotenuse of a triangle. the water the next long edge and the line the shorter edge at a right angle from the water.

The short edge no matter the line weight does not have drape. The more the force of gravity aligns with the presentation angle the less the drape. Gravity causes more drape as you move from perpendicular to parallel of the water’s surface…no matter the weight of the line.

With a longer line you are moving to an angle where gravity has more force on the line itself.

Going to a stiffer lighter line is one way to help reduce drape.
One can also reduce drape by fishing a shorter line and reducing presentation angle.

Consider a spider web thread…no matter how light it is …it will still drape under its own weight.

LL is much more rigid than furled leaders. It is slightly more rigid than nylon. Rigid lines help reduce drape, as more gravity force is required to overcome the stiffness. That dyneema line is also strangely rigid…and unlike a lot of furled leaders, seems to hold less water. That combo has me reaching for it recently. I also need to get my hands on the 50# version of it. It could be a winner or looser…as currently i am pleased by my mr magoo discovery of the 65#. I have 50# spectra, but have not cast it…it just seems too light and flexible. Might try this weekend.

[Gressak]

I also believe that this thread is both therapeutic and entertaining.

A lot of this discussion is in nuances and highly relative to skill level and fishing style.

As I noted, I do not notice any change in productivity not matter the line I fish, and lately it has been a mixed bag…even using 2.5 LL.

I feel like I can adapt, and my grotesque approach to fixed line fishing is not refined enough care a ton about finer details. I do not have the casting skill to have my tippets mended correctly on touchdown. I cannot cast to the center of a desert plate. I do still have fun and catch my share of fish. I guess when my skill is ready for those refinements perhaps I will have a more refined preference.

What I find interesting though is that people no matter the topic or discipline get easily caught up in trends. Full flex rods, ultra light line presentation, short line, long line. All this stuff is good for the industry and it is good for us in discovering what we like…but it is also has attributes of a wild goose chase.

I am digging the dyneema line becuse it works and I do not have to straighten it. I am finding that even with the tips in removing memory with LL I am still not able to get the memory completely removed to my satisfaction. The dyneema stuff is also cheap enough that I feel like I can experiment with it a bit more.

[Peder]

@Gressak

I also believe that this thread is both therapeutic and entertaining.

A lot of this discussion is in nuances

Completely agree! Regardless of whether we discuss and debate or not, and whether we like it or not, science still impacts our fishing. Besides it’s fun to learn new things and be pushed to refine our own thoughts.

and highly relative to skill level and fishing style.

I’ll need to think about that a bit more.

[Gressak]

@Peder

and highly relative to skill level and fishing style.

I’ll need to think about that a bit more.

This statement is sort of like that offlined conversation we had.
The difference in approach and philosophy, from angler to angler.
There is so much stress on things that spook fish and drag free drifts.

Although a traditional fly fisherman is concerned with drag…they are utimately always employing more
drag than the worst tenkara angler, yet they still can be very, very, sucessful.

I have a buddy who I converted to a fixed line flyfisherman, and who employs no stealth and does not follow or read any tenkara resources. Yet often he out fishes me. Me, a guy who follows a lot of tenkara rules. I know he would laugh at most of these technical discussions. Sort of like how we may tend to laugh at the focus of a literal “Match the Hatch”.

[dwalker (David Walker)]

It is not to difficult to calculate the theoretical maximum horizontal casting distance for any combination of: rod length, line length, height of the butt end of the rod, and angle of the rod. If you assume perfectly straight lines. The actual casting distance in practice would be shorter. To figure out the actual casting distance, accounting for line sag, would require a lot more information about line weight and a lot of dealing with centenary curves. More effort than most people would be interested in doing. Then on the stream wind would introduce new factors.

However, a lot of people, from time to time, do get interested in thinking about the idealized maximum casting distances. Or even the shortest and longest effective fishing range. And giving it a little thought can provide some insight into what changes to your system will really do for you. I myself got interested in this short of thing six years ago. I think one of my major insights was discovering a 2 foot longer rod, will not let you cast 2 foot farther away. You only gain about half the distance as the increase in rod length. For example a zoom rod going from 3.9m to 4.5m. Is about 24inch extension.

Here are a few links from people who have given this kind of thing some thought in the past.

tenkarakebari blog Line Lenght

The above webpage has this interesting table. But all the combinations of rod length and line length use lines longer than the rod. From 1.28x for the 5m rod + 6.4m line at a height (h) or 1 m. to 18x for the 3.5m rod + 6.3m line at h of 2m.

Where:
h = height of rod butt above ground. See the diagrams on the webpage.
Column 1 = Rod Length (竿長)
Center Column = Flying/Flight Distance (飛距離) , aka casting distance.
Right column = Line Length (ライン長)
Units (単位) = m, meters.

The most interesting thing is if you calculate the ratio of casting distance ÷ (rod length + line length). Almost all of them come out close to .71.
iow casting distance will be about 71% of the total length of rod length + line length.
Regardless for the h value. At least for all the combinations the author used. And notice that he increased line length as h increased.

The author also wrote something I am not sure I agree would work with other combinations of rod length + line length.
That casting distance or the horizontal distance on the water, (水平距離) = 1.414 * z + h.
Where z = rod length, and h = height of rod butt above ground. And 1.414 looks like the square root of 2 , to me. 1.41421

For example, on this next website, which sadly is now missing one diagram, the above formula doesn’t work. However he is using a 3.6m rod + 7.2m line. At an h of 1.5m. The above formula gives a horizontal distance of 6.59m, But his diagram shows 8.5m. Or 78% of the sum of rod length + line length. A little higher percentage that the previous table. Maybe this only happens when line length is 2x rod length. I doubt many people fish with a line that long. 1.375x is as long as I am comfortable fishing. Occasionally a little longer. But most often 1.25x.
https://plaza.rakuten.co.jp/tenten2005/diary/200711050000/

And of course my own explorations from six years ago. Done in public where some people gave the same reaction that Gressak mentioned. wth?
TUSA Forum Daniel’s Article on long lines

One of the more interesting casting diagrams was on a website that has disappeared off the web. However, I can find it on web archive wayback. But it lacks the diagram, that included some practical considerations. Such as at what distance do you hit a red zone where the fishing efficiency would be poor due to too much line on the water making the kebari move unnaurally. Fortunately, I also saved the diagram. And my explanation or understanding of it.

archive of Master of Tenkara Line System

This diagram is intended to show the effective casting & fishing range when using a 3.6m rod with two different lengths of line, a 5.5m line and a 6.9m line. Assumes casting distance to surface of water, from full height of fisherman, ie not wading. So a more practical or common setup used by more people.

Rod height 1.7m (5’7”) with 3.6m ( 11’10”) rod.

Red/Blue diagram line for fising lines of either of two ratios, - total length of 5.3m ( 17’5”)
a) 3.6m line + 1.7m tippet = 5.3m ( authors preference is to use long tippet)
b) 4.5m line + .8m tippet = 5.3m ( author says a beginners set up )

Black dot or Red dot lines
Both are 6m ( 19’9”) + .9m ( 36” or 3’) tippet = total length 6.9m (22’9”)

Basic summary is you can effectively fish over a range of 2.25m ~ 7m ( 7’ 5” to 23’) when using a 3.6m rod + 5.3m line.

You can effectively fish a range of 5.5 ~ 8m ( 18” to 26’) when using a 3.6m rod + 6.9m line. But if you lower the rod to 10:00 , 30 degrees, with the same line you hit the red zone from 8m to 9m and the line will be to slack with to much line on the water , resulting in unnatural movement of the fly and you can not fish this range well with this set up, the fish will ignore the fly.

If using a 4.5m rod + 6.2m line the effective fishing range is longer, extending from 4.3m to 9.5m ( 14’ to 31’3.25”) The bottom rectangle box below the graph.

This is fun stuff only if you’re into this sort of thing. But not to long, Then there’s this

Schrödinger's Rooster starring Foghorn Leghorn

Some things are just not understandable.
After a while pondering, it is best to just go a fishing.

[Gressak]

Thanks again David for all the data. Very interesting stuff.
I was able to read it and some of the off shoots.

I found a link in one of those links. On tuck casts.
hahahahah…oh the horror. Standing out in the open with all that line darting
around and splashing on the water. A Barbarian.

How to Make a Tuck Cast | MidCurrent

Just the same, I bet that guy outfishes me…hahahahaha.
That video does put some of this discussion into perspective.

The nuances we discuss… are all technical considerations but may not factor as much as one thinks.

Some fish are just wired with a hair trigger and no matter your stealth will be alert of your presence. Some you can stand over waving your arms around and still they will take your offering.

[Gressak]

made an illustration.

The longer the line, the increase in the necessary presentation angle,
the greater the affect of gravity, the more pull on the fly.

[dwalker (David Walker)]

I think probably the case can be made that if you want to fish at a longer distance it would be better to use a longer rod with a line that is not over 45% longer than the rod. Rather than using a longer line with a shorter rod. That as you point out in your drawing keeps a higher rod tip, with its advantages.

Another thing that should be considered that affects or ie it effects?, line sag is river current pulling tension in the line from drag of kebari, No effect on the amount of line sag in still water, but only in moving water. The point being that if fishing still water use a shorter line, if fishing moving water you could maybe get away with a longer line and have less line drape.

Another interesting thing can be deduced if you think about the previous casting distance diagram. This one:

Which is the total area that can be fished with different combinations of rod length and line length.

The two shaded rectangles below the x-axis are for two different combinations,
The upper box is for a 3.6m rod + a line of 5.3m. Or 1.47x rod length.
The lower box is for a 3.6m rod + a line of 6.9m, Or 1.91x rod length.
They represent the distances that can be cast to and fished, Except for the red shaded are, which the author concluded could not be effectively fished, rod tip to low for the 6.9m line, to much line on the water, and not enough line slack to effectively drift the kebari in a natural manner.

Of course you don’t spend your whole day fishing in only one direction. 270˚ west for example, You can fish a 360˚ circles. If you take a bird’s eye view and swing the diagram 360 degrees, you end up with concentric circles. You can calculate the area of those circles, subtract out the area next to the angler that can not be fished, and find the square meters area that can be fished.

The 3.6m rod with 5.3m line can be fished at rod angles of 10 o’clock (30˚ from horizontal) to 11:30 (75˚), and be fished from about 2.3m out to 7.3m, without to much line on the water or to much line sag, This give an area of about 151.5 m^2,

The 3.6m rod with 6.9m line can be fished at rod angles of 10:30 (45˚) to 11:30 (75). And over a range from about 5.5m out to 8m. The author regarded that area beyond 8m as the red zone, not effective area to be fished, though it could be cast to. So that area is excluded, This leaves a fishing area of 106m^2.

Surprisingly, a 30% smaller fishing area than the shorter line combination could be effectively fished, Not a bad choice, I recall reading somewhere that some researcher determined that most fish are caught when fly fishing within 27 ft, (8.2m) of where the angler was standing.

Taking the author’s concept (perhaps with other assumptions about the range of effective fishing distance) and applying to a different combination of a longer rod, with a line not over 1.47x rod length might reveal other surprises about rod angle and line sag, and effective fishing area.

Or just go fishing and not think about such things to long.

otoh, other people make different assumptions about good rod and line combinations.

If you have seen the video, Tenkara in the Land of Little Rivers, which included Dr. Ishigaki’s tenkara presentation in 2009 at the Catskills Fly Fishing Center, you may recall his recommended 4 listed line and rod combinations. 4 m rod with 4m, 5.5m , 7m , & 9.5m line, The last one later revised to a 4.5m rod with 10m line. So clearly other people have other ideas about that.

Tenkara in the Land of Little Rivers p.2

Or you can see a slightly different version of the same combinations from 2013 on the tenkarakebari blog
Tenkarakebari blog テンカラ三昧

Personally I don’t like fishing a line longer than 5.5m with a 4m or 4.5m rod. But more often 4.5m to 5m line. Though I’ve seen enough videos of Japanese tenkara anglers to realize that fishing with a 4m rod + 6m line + 1m tippet seems to be a more common popular combination when fishing on bigger rivers. Though I do try it, just to see how it goes, now and again.

Longest rod you can get away with, plus a not too long line and tippet seems to be the best way to go, to keep high rod tip, and line off the water. And maybe a little analysis of the chosen combination might reveal a surprise about which combination allows you have the largest fishing area.

[Gressak]

It depends on the water you want to target.

I often target and catch fish closer to me. Sometimes the foliage and terrain is such that shorter line is better. It can also be preference.

In the diagram…imagine a bank of bushes and overhanging trees behind the angler.

The longer line can not be fished effectively in the non overlapping blue area. Yes can you can catch fish, but hookset is a problem. A short line can fish both areas if the angler uses his/her legs.

[tvdavisid (Tom Davis)]

Not very scientific, but here’s a line comparison I did a while back:

Tenkara Line Sag (drape otsuri) comparison-- Soft Tenkara 3.3 v. #4 v. #3 fluoro level lines

-Tom

[Peder]

So, here’s some playing around that I did today. I know it’s not 100% scientific and there are numerous variables in here, but I was doing the best I could with my available time and materials. If I have more time, I may play around with it a little more to level things out and make more specific comparisons. This would include:

• Identical line lengths
• Same size tippet rings
• No line cards

As I’m sure you can likely see, my little scale here can measure as low as 0.1gr, which I think is important to note in relation to the specific weights below.

1. 4.5m spiderwire invisibraid (0.40mm diameter) with 3.5mm tippet ring = 0.8g
   

   

2. 5.5m spiderwire invisibraid (0.40mm diameter) with 3.5mm tippet ring = 1.0g
   

   

3. Empty line card = 2.8g
   

   

4. 5m 3号 nylon LL (0.285mm diameter) & 2mm tippet ring = total weight - line card = 3.3 - 2.8 = 0.5g
   

   

5. 4.5m 2.5号 fluorocarbon LL (0.260mm diameter) & 2mm tippet ring = total weight - line card = 3.3 - 2.8 = 0.5g
   

   

6. 4m 3号 fluorocarbon LL (0.285mm diameter) & 2mm tippet ring = total weight - line card = 3.3 - 2.8 = 0.5g
   

   

7. 5m 3号 nylon LL (0.285mm diameter) & 2mm tippet ring = total weight - line card = 3.3 - 2.8 = 0.5g
   

   

As you can see, my scale is not specific enough to measure the differences in weight between 4m, 4.5m, and 5m lines and possibly the minute differences between nylon and fluorocarbon or the different line weights.

One interesting thing to note that I’m curious to investigate further with some of the variables removed is this. The 4.5m invisibraid is 40% heavier than the 4.5m 2.5号 fluorocarbon LL (in fact than either fluorocarbon or nylon regardless of length or size). It also has 46% bigger diameter. One question I have (amongst many) is what about density? How does the density of the invisibraid compare to fluorocarbon or nylon? I think it is rather curious that the various LL materials, lengths, and sizes all equaled the same weight. That was completely unintentional in this little experiment. I just grabbed some lines out of my fishing bag.

[Peder]

@Gressak

The reason for the drape is not just a factor of weight…no matter the line. It is also presentation angle.

Absolutely. Although, that is why I reference the proverbially perfect 90°. Obviously, so much of hypothesizing is about removing as many variables as possible and presuming ideal conditions. That being said, there will never be ideal conditions when we’re out fishing; but, it’s fun to think about and experiment with (for me at least, maybe not someone else). I do think, though, that the type of line that we use does have a huge impact on our fishing.

Consider your rod the hypotenuse of a triangle. the water the next long edge and the line the shorter edge at a right angle from the water.

Ahhh, here’s one assumption that I made and I see we looked at it differently (I’ve now updated my earlier post to make more sense). I presumed that the surface line of the water was the hypotenuse and the the “ideal” 90° was between the rod and line (and I’m still sticking with this ) as seen in the bastardized image below.

@Gressak

Going to a stiffer lighter line is one way to help reduce drape.

I don’t know if I agree with this. I don’t think it reduces drape; rather, I think it simply changes the shape of the drape. This is because gravity is a constant.

One can also reduce drape by fishing a shorter line and reducing presentation angle.

Completely agree with you here. I think the keiryu “lantern fishing” attempts to do this, with really long rods and short lines (not to mention split shot); I digress and get away from tenkara here.

It does indeed depend on the type of water you want to target. I think we’d have to agree on what variables we’re going to cut out or allow in our hypothetical scenario to consider the drape/otsuri of the line. I presume you’d agree with this @Gressak (though I could certainly be completely wrong), that we cannot reasonably compare the drape of 4m of line fished on a 5.3m rod with 5.5m of line fished on a 4m rod. That would be like comparing the drape of a banana with that of a string bean .

@dwalker I agree with you that river current (and wind) both have an effect on drape. I was simply removing them from consideration for a more simplified analysis.

@dwalker

The most interesting thing is if you calculate the ratio of casting distance ÷ (rod length + line length). Almost all of them come out close to .71.
iow casting distance will be about 71% of the total length of rod length + line length.

This is interesting. I wonder if this is at a specific angle or not? Unfortunately, I don’t have the time to look into it further at the mo’.

It is not to difficult to calculate the theoretical maximum horizontal casting distance for any combination of: rod length, line length, height of the butt end of the rod, and angle of the rod. If you assume perfectly straight lines. The actual casting distance in practice would be shorter. To figure out the actual casting distance, accounting for line sag, would require a lot more information about line weight and a lot of dealing with centenary curves. More effort than most people would be interested in doing. Then on the stream wind would introduce new factors.

This is also interesting to think about in reference to the overall drape of different lines. I think you also make a very important point here. Almost all of this entire thread (at least from my perspective) is assuming straight lines and not factoring in wind or water velocity. Within the context of this discussion at least, maximizing casting distance would be a side benefit of the reduction of drape.

I’d have to pull out my compass and pencil (which aren’t too far away), but in reference to your diagram here; I wonder at what lengths a longer rod/short line would overlap with a shorter rod/longer line for fishing area? Undoubtedly, each would pose positives and negatives and each would have its supporters and naysayers.

I have to say, this thread is why I loved teaching science (for the few years I did it). Because you can apply science to real life and real things that people love. Then in the end you can just say, “hell with it, I want to catch some fish” and use whatever rod and line you have and have a good time.

[dwalker (David Walker)]

@tvdavisid

here’s a line comparison I did a while back:

Interesting comparison. There was a drawing a guy did trying to compare ideally the difference in line sag between lines of weights and show how that also changed rod angle, but I can no longer find it. I think it may have been the drawing now missing on the link I posted earlier. Onthe tenten 流れのままに blog.

I fish with #3 FC LL fairly often, #2.5 when wind allows, occasionally #3.5. And despite the soft tenkara lines being nylon. The taper seems to cast well for me on windy days. The great irony is spring is often the best fishing, but also the most windy. On days when my line is like a flag in 23mph or higher winds, I go hiking.