Matching line & rod weights...some reading material

[Andrew]

I was looking for information on converting grams to grains so I could label some shooting heads (I'm lucky enough to have access to high-tech scales here at work). In the process, I came across this article by somebody named Tom Kirkman, which is somewhere in this website (http://www.common-cents.info/). I don't particularly care too much either way about the "common cents system", in that I'm not about to go out and rig all my rods up to various contraptions. But I do think the text of the article I've pasted below, and some of the other stuff on the common cents webpage might be of interest to some of you who enjoy discussions about matching lines and rods. I happen to think the article below is spot on...

From Kirkman's article:

"I’ve been involved with fishing of some sort or another
for several decades now. During that time I’ve had the
opportunity to speak to thousands of fishermen and
rod builders from around the world. It dawned on me
long ago that perhaps the most misunderstood segment of
the tackle market concerns the numbering system used for
fly rods and fly lines. Most fishermen, and many rod
builders, have never really understood it. For those of you
who don’t understand what these numbers mean, let’s take
a quick look.
Fly rods are no different than spinning or casting rods
in that they require some manner of weight and some
amount of angler input in order to load and cast. In fly
fishing, you cast the line, not a lure or sinker. Depending
upon the fly you’re casting and the fishing situation you’re
in, you may need to cast lines of varying weights. Thus, a
system was devised to properly match these various
weight lines to the rods that would best cast them. This
system consists of a set of numbers ranging from 1 to 15,
with each number assigned to represent a specific amount
of weight (in grains). But unlike a sinker or lure that has a
fixed weight, the weight of a fly line will vary depending
upon how much of it you have past the tip. So AFTMA
had to arrive at a constant length of line from which to take
their weight measurements. They settled on measuring the
weight of the first 30 feet of line. At that point, it became a
simple task to design specific rods that would work best
with 30 feet of any specific line past the rod tip.
Let’s use an AFTMA5-weight line for an example. The
standard for the first 30 feet of a 5-weight line is 145 grains.
Thus, a 5-weight rod should fully load with 30 feet of such
a line past the tip. Now because any rod will cast with a bit
under, or over, the optimum casting weight, the fisherman
can expect that his 5-weight rod will still cast fairly well
even with a bit less or a bit more than 30 feet of that 5-
weight line past the tip. Remember, however, that when he
has less than 30 feet of line past the tip he has less than 145
grains to cast with. And when he has more than 30 of line
past the tip, he has more than 145 grains for casting. But as
long as he doesn’t go too far in either direction, he’ll be
okay. In fact, he’s most likely to find that his matched 5-
weight outfit will cast and fish nicely at distances of from
about 25 to 65 or 70 feet. And that’s a pretty good overall
range for most fishing situations.
Now what happens if he decides to fish in really close
- maybe a small stream where he’ll never get more than
maybe 15 feet of line past the rod tip? Not a problem. He
still needs 145 grains or so to get that rod to load. He
obtains that 145 grains on 15 feet of line by moving up a
line number or two. So instead of a 5-weight line, he
selects a 6-weight line for use when he’s fishing in really
close. The rod still feels 145 grains, so it casts fine.
Now let’s move out to the far end of the spectrum.
Let’s say the guy is going to be fishing at very long distances
and pushing perhaps 80 to 100 feet. He may well
carry 50 or 60 or more feet of line past the tip before his
final cast. He still needs 145 grains on that rod and our 5-
weight line at 60 or more feet is going to weigh much more
than that. But again, it’s not a problem, as he can just drop
down a line size to a 4-weight line and find that with
around 50 to 60 feet of line out there past the tip, he’s
wound up right back at 145 grains. Perfect.
This is and was always the premise of the AFTMA line
numbering system. Lines and rods of the same number
were designed to match and work well together with about
30 feet of the rated line past the tip. If you were fishing in
really close, you moved up a line size. If you were fishing
out really, really far, you dropped down a line size. What
could be simpler? Nothing, really.
But when one company rates a rod for 20 feet of line
past the tip, and another rates a similar rod for 40 feet past
the tip, well... you see the problem. We don’t even have
any consistency among the makers themselves. Many rate
their 4-weight rods differently than their 8 weight rods. Or
their shorter rods differently than their longer rods. There
simply is no single standard in use across the board.
There’s a lot of talk these days about creating a new
standard for fly lines and fly rods, something that might
eliminate the confusion which we have now. But there’s
really no need for it. The original AFTMA system made,
and still makes, perfect sense. But you have to understand
what it’s based on - 30 feet of line weighing a certain
amount and a rod intended to optimumly load with that
particular weight. Once you understand that, you can correctly
match that rod with any line at any distance or situation
you plan to fish. We don’t need a new system, we
need to understand the original AFTMA system. It’s simple
and it works. Let’s use it."

[WhipFish]

Personal joke- I'll use bigger hooks when you type smaller posts.

I tried reading it all but my narcolep [zzzzzzzzzzzzzz]

[jaybp30]

That is pretty interesting. Has anyone seen a rod manufacturer state the amount of line a rod is rated for? I have never noticed this. Also, does this imply that you will have a more delicate presentation loading a 4# with a 6# line if fishing in close? I doubt it, to me it sounds like he is saying the casting will be easier. But then again, wouldn't that translate into more control and therefore more precise casting.

[Adam Taylor]

Jay-

Some rod companies will tell you what the grain "window" for the rod is...with the growing popularity of spey rods we may see an increase in that type of delineation (sp)....it may simplify things a bit.
I rarely go by what is stamped on the rod...I usually will toss a couple of different lines until I find one that fits....

[pvansch1]

About three years ago at The Catskills Rod Makers Gathering, a gathering for bamboo rod makers, they set up a "Common Cents" board to measure out rods. They went through well over a 100 classic rods from the "Golden Age" of bamboo rods. Then they weighed out rods made by current makers based on the older tapers, plus new tapers the makers had developed.
It was an interesting study to see just how accurate the system is. The rods were available to cast with the designated line weights.
The biggest variables in casting the rods was the lines, both in weight and suppleness. Bamboo rods tend to like softer lines.

Some additiona info on line weights;

"Here is a basic rule of thumb... Say you have a WF-5-F with 30 ft.
head. It will weigh the same at 30 ft. as a DT-5-F. Beyond 30 ft. the WF
will gain little weight, the DT will gain much more. For every 5 ft. of
additional belly of the DT line it gains the equivalent of one line size of
weight. Meaning, at 30 ft. both lines will weigh 140 grains. At 35 ft. the
WF will weigh slightly more than that, the DT will weigh approx. 160 grains
(the weight of a 6 wt. at 30 ft.), at 40 ft. it will weigh approx. 185
grains (the weight of a 7 wt. at 30 ft.)
So to roughly figure the length where a lighter DT will surpass the weight
of a heavier WF is pretty simple. A DT-4 will weigh approx. the same as a
WF-6 does at a length 10 ft. beyond the head length of the WF-6.
This rule of thumb is pretty accurate as long as you don't take it to
extreme and start comparing 3 wts. to 10 wt.s, but for comparing lines 1-3
line sizes apart it is pretty close."

[MuddlerMinnow]

I wonder if my wife's kitchen scale is accurate enough to do this? 1 gram = 15.432 grains.

[pvansch1]

The sell line scales, if not the postal scales will do it.

[Andrew]

I wonder if my wife's kitchen scale is accurate enough to do this? 1 gram = 15.432 grains.

My shooting heads varied from about 10 grams to 25, so if it has that sort of resolution, then yes.

Remember, though, if you're measuring a full line, you want to weigh only the front 30 feet. (PS - don't cut it off to do this!)

[Catch 22]

A number of years back, I was fishing with a friend who was complaining that his G. Loomis GL3 5 weight was too stiff, or fast. I had the same rod, so we switched, and sure enough, mine flexed further while casting the same amount of line. I voiced the opinion that maybe it was because we had different brands of line strung up, but neither of us thought much of it at the time.

Fast forward a few years, and I'm fortunate enough to be in the Catskills casting a whole bunch of bamboo rods courtesy of a great bunch of guys (with a whole lot more money than me). One of the guys had every single rod of his (10+ rods) fitted with a line that made every rod cast amazingly. I was afraid to just hold some of them when I found out how much they were worth! But the point is that this man spent a lot of time finding the perfect line for every rod, trying all different brands and tapers on each and every rod. And the results were spectacular. Every one of them was a masterpiece.

A year after this, I picked up the bamboo rod of my dreams. Very expensive by my standards, not even on the radar by the Catskills guys' standard. I had cast this model of rod before in the presence of the maker, and it cast like a dream for me. It was perfect. When I picked it up, I fished with the maker, and it cast poorly. I realized why the next day that I had a 3 weight line on a 5 weight rod. Oops. So I took a several 5 weight lines, and a 6 out to the Farmington, to try on the rod. It was much better (duh) with the right line, but still nothing special.

I asked the maker what line he used when I cast it, and he wasn't sure, maybe a SA XPS WF5F he thought. About that time, I asked a couple of other guys who had the same rod what they used, and they both recommended Wulff lines, the Triangle Taper and the Long Belly. Well, I managed to pick up a used one of each line, and WOW!, what a difference. The rod came alive. I fished the Housatonic the next night, and while standing on a subsurface rock, threw at least 60, probably 70 feet of line out with no problem. And I am not a distance caster. I'm a stalker, I usually fish in very close, and laugh at the people trying to cast far with a fish rising 10 feet away. After a little checking around, it seems that both the SA lines and the Wulff lines are on the heavier end of the range of AFTMA line specs for their weight class, so my rod prefers something more like a 5 1/2 weight line.

Another thing that might be a factor besides the weight of the line is the person's casting stroke. Some people have a very aggressive stroke while others are more relaxed, more of letting the rod do the work.

The bottom line (pun intended) is that you should try as many lines as you can with each rod. The performance you may obtain from the rod can be worth the effort, turning a rod you thought was a dog into an excellent tool. Or better yet, turning a good caster into a great one.

Jeff

[Gary]

The guys I know that fish triangle tapers love them and will not ever go back to a WF or DT. I only own one in a 9wt. intermediate and I really enjoy it in the Salt and fresh water bass fishing. My next trout line might be a triangle taper floating line. I would need to sample it on the rod I use most before I buy.

[paddy]

I am fortunate to have my RCBS reloading scale that has grains and grams.