AFTM Numbers

What’s this?
A new initiative to post some information primarily designed for novice fly anglers, if you see “The Beginners Page Logo” it means that the post is primarily designed to help novice anglers but of course everyone is welcome to read and comment. I hope that you will, it might help end up with a better product overall.

The Beginner’s Page logo is designed to show that the post is primarily aimed at novice anglers.

The Beginner’s Pages: The AFTM system, it seems logical and sensible but the system has real problems which you should understand, at least a bit.

The AFTM system is nominally a means of matching line weights to the rod and on the face of it a pretty simple and sensible way of doing that. AFTM stands for Association of Fishing Tackle Manufacturers.  

You will almost definitely be aware that at least to some degree “the line should match the rod”, that is to say that if you are casting a weighted line then you need a suitable rod to cast that particular weight most effectively.

So, the AFTM system is designed to provide at least some sort of guidance as to which line to cast on which rod. The system defines the mass of any given fly line based on the weight of the first 30’ of line (excluding any level portion at the front) by measuring that weight in grains and then converting to a simple number.

In case you are wondering, a grain is a pretty small measurement of mass; approximately 64.79 milligrams. There are a thousand milligrams in a gram and a million in a kilogram. There are then approximately 15432 grains in a kilogram. Grains are small amounts of mass, that’s the point.

Taking the lines, weighing them and giving them a number is at least objective, you should find that any line measured as, let’s say, a five-weight line, should perform similarly to any other line with the same AFTM rating. You do know at least that the first 30’ should weigh the same.  (We will see in a minute that all is not necessarily as it seems, but at least we have a pretty objective test to start with).

The second part of the equation is that every fly rod has a designated AFTM rating supposedly showing the ideal line weight to be used with that rod, again it seems pretty straightforward, except that whereas the weight of the line is at least measured in some sort of scientific manner the designation on the rod is little more than a guess. There is no standardized means of determining if a rod is a #4 or #9, so unlike the weight of the line the designation written on the rod is highly subjective, pretty much just the opinion of the rod builder.

Much of the time that will still suffice for the novice angler, and as a base point it is probably the best option to simply mate the rod designation with a line of the same designation. (It is highly recommended that if you are a novice, you get some help from the guys at your local fly shop).

Where the problems come in:

Firstly: there is a very simply issue and that is that there is no standard as to what line casts best with which rod, one angler may prefer this and another angler prefer that. Not to mention the guy on a small stream is casting a lot less line than the angler on the side of a lake. In reality you can (perhaps with some difficulty) cast any line on any rod, so the numbers aren’t set in stone. 

Secondly: The line weights as designated #4, #5, #6 etc include lines within a band of weights, so, even measured correctly two different #5 weight lines may not actually have the same weight for the first 30’. Looking at the table above you can see that the maximum variation for a #5 line to still be a #5 line is approximately 8%. Imagine if you and your mate both ordered a beer and your glass contained 8% less beer than his, you might feel rightfully miffed. 8% is a pretty large variation.

Thirdly: Even if the weight of the first 30’ of two different lines is exactly the same there is the issue of the taper. The taper, is the shape of the fly line; fly lines are universally tapered, they don’t work properly if they are not. But there are hundreds of variations of taper, usually designed for different casting or fishing situations. In essence what the taper and the AFTMA number mean is that if you are casting 30’ you should be casting the same overall mass. BUT, and it is a big BUT, if you are casting 20’ of line with two different #4 fly lines the mass most likely won’t be the same.

Fourthly: There is no clear means of defining which rod works best with which line, for a start, a lot of that is up to the caster, the way they cast, the distance they want to cast etc.
In fly casting, it should be obvious that there is no one ideal weight to be casting with any given rod. We are casting different distances all the time and as the line has mass each time we change the distance we change the mass we are throwing. So, with the best will in the world there is no ONE weight that can be said to be correct. (if lines were level and not tapered a #5 line would weigh 4.66 grains per foot. If you cast 30ft the line would weigh 139.8  grains and would behave like a  #5 weight, BUT, if you cast 35ft it would weigh 163 grains equivalent to a line designated as #6 weight. As Simon Gawesworth at RIO fly lines often explains, the difference between a #5 and a #6 line at 30’ is about the mass of a standard business card !!! (about 25 grains). The whole system, although at first glance simple, is actually complicated and confusing I admit.

MORE PROBLEMS:

The above issues are problems which are entirely built into the system as it stands, an error allowance of something like 8% and the fact that we cast different distances and therefore different mass all the time. Plus that there is no specific means of measuring the AFTM number of a rod in the first place, that all makes it more tricky that it looks at first, however there are further problems with the way it all works.

For some time, fly rod manufacturers have been driving demand for what they refer to as “fast action rods”, supposedly they recover from bending more efficiently but at the same time they are to all intents and purposes simply stiffer. Perhaps one way of doing so, although I couldn’t prove this actually happens, would be to simply take a rod that was previously designated as a #5 weight and call it a #4 weight. With a #4 line on it, it would seem stiffer when casting and this has been something of a trend now over a number of years. One equally needs to bear in mind that fly rods are flexible levers which bend in a progressive manner, the more force applied the more they bend into thicker sections of the blank, so again there is no ONE answer to what mass works best. Push that too far and the average angler can’t cast rods that are that stiff, (fundamentally because they don’t match up well to the lines being used).

So, the line manufacturers started to come up with lines which are heavier than designated by AFTM. Generally, they give them some sort of additional notation such as AFTM + or similar, but in effect they are cheating the system. Also, they often don’t tell you, so you have no idea that your lovely and easily cast #5 weight line is in fact a #6 with a different label on it. (I have to admit though that the line manufacturers have to some degree been pushed into this by the rod manufacturers, because actually few people can cast these “fast” action rods, which they keep pushing, without “overloading” them)

As a general rule, particularly if you are a novice ,it feels much easier to cast a line heavier than the one specified on the rod, a LOT of that is due to poor casting technique but one expects that with a beginner. What has happened though is that this “overloading” either intentionally or otherwise has become almost standard.

It is a bit of a joke because the rod manufacturers are all saying “people want fast action rods” and the line manufacturers are saying “overload them to slow them down”.. Who is right?

I would still say that as a general rule if you are a novice you should go with a line nominally rated the same as the rod, if you can get expert advice from a pal, the fly shop or whatever go with that. But beware, what was once a rather subjective but at least simple system has become a minefield of complexity and I might be tempted to add, dishonesty too.

As things stand, about the best that can be said for the system is that it offers a loose guideline to matching lines and rods, a very loose one. If it is at all possible you want to test out different lines with different rods before you purchase them. Equally if you are a novice, I highly recommend that you don’t get trapped by the “fast action rods are better” mantra of the marketing department. It is true that they perform more effectively when an expert caster is aiming to cast the furthest in a casting competition, but that in no way relates to what you generally want when on the water.

The top end of competition but not much good for a trip to the shops.

It may well be the case that Lewis Hamilton’s Formula One Mercedes is the quickest thing on the road, one could reasonably perhaps prove that to be true. However, it probably isn’t going to be the ideal transportation for a family of four, heading to the shops for some retail therapy. Even if you could manage not to stall it when leaving the driveway, where would you put your parcels? or for that matter the kids? The point is that what might arguably be “the best” in one situation, is undoubtedly NOT the best in another. Super fast (stiff) fly rods used for distance casting competition have no place out fishing and there is little if any reason to assume that they would be of any benefit to the angler, novice or not.

To my way of thinking this obsession with super fast action rods simply doesn’t make sense when compared to most fishing situations, after all, these things are fishing rods not casting rods. They need to provide the angler with some “feel” and control and to be able to perform at different distances with some level of comfort. In general rod and line combinations which are “slower” in action and provide more feel for the caster, particularly the novice caster, are going to perform better and feel much more pleasant to fish.

For a more humorous discussion on the subject you may also enjoy reading a post from this blog from some time back. https://paracaddis.wordpress.com/2012/03/15/an-aftma-fairy-tale/

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Fly Casting is Difficult, isn’t it?

The Beginners Pages: Is fly casting difficult?

Having become more than a little frustrated with a lot of the “fly fishing instruction” I find on-line and so I have decided to embark on a “mini-project” of addressing some issues which I hope may primarily be of interest to novice fly anglers or those simply thinking of starting out with fly fishing.
What I intend to call “The Beginners Pages”

Where a post on “The Fishing Gene Blog” is designated with “The Beginner’s Pages” logo the idea is that it is primarily about something which I hope might be of particular use to the novice. Of course, that doesn’t mean that anyone else can’t gain something from it. Hopefully, if some more advanced anglers have ideas or comments, that might help this grow into an even better resource. Novice angler or experienced expert, if you have some comment or input, please do feel free let me know in the comments section. Equally if you have suggestions for topics I would love to hear from you.

To start off I want to address this notion, which seems widely held, that fly casting is tricky, that it was somehow invented to make things harder, to frustrate us all and leave us scowling on the riverbanks with hooks in our ears and in the trees. Something far too difficult for mere mortals to so much as attempt. I have, sadly, known more than a few fly anglers who delayed their start in the sport because they always thought that it would be too difficult to learn. Later, as accomplished anglers they bemoan the years of opportunity lost simply because they thought they would never manage something that now gives them endless pleasure. Fly fishing isn’t fly casting, but of course, you can’t be proficient at the former without mastering the latter. It is something that puts a lot of people off where it shouldn’t. Perhaps understanding a bit about how fly casting evolved helps, it wasn’t invented to make things hard, it was invented to provide a solution and anyone can learn to do it.

“Why is fly-casting so weird?”

The apparent origins of fly fishing came from some ancient Greek guys tying bits of red wool on a hook and tempting the fish to eat it in the belief that it was food, specifically insect food.

Whether the Greeks imagined this more effective than other forms of fishing or if they were just tired of getting worm guts all over their nicely starched togas isn’t clear. But certainly, even back in the times of the Ancient Greeks, it would be pretty obvious, to even the casual observer, that some fish, particularly trout, eat insects. One can easily watch a hatch of flies on a river and see the fish intercepting them. If you were up for some sport, or simply hoping for a bit of protein to add to your olive oil and eggplant supper after swinging swords and throwing javelins all day, trying to imitate the flies that the fish were quite obviously eating would seem like a pretty cunning plan.

Even the casual observer would realise that fish eat flies.

So, with that idea, came more than a few problems, one of them, but far from the most difficult to address, is how to imitate tiny insects on a hook? Another, in fact more problematic consideration, how are you going to “throw” that imitation far enough to catch a fish, given that it has no weight?

Flies, both real and artificial don’t weigh enough to be thrown

In essence, those two considerations are the exact reason that even today fly-fishing gear and fly-fishing techniques look very different to almost any other form of angling. It is important for the novice to understand however that fly fishing isn’t more clever or more difficult than any other form of angling (I might add that a lot of us do find it more rewarding, but that’s a different discussion).

The, “how to imitate an insect on a hook” problem was initially solved by the very simple “cheat” of attaching real bugs to the hook. Even today this form of fly fishing is practiced, with live “Daddy Long Legs” or “Mayflies” in a style known as “Dapping”.

But in time the need to imitate insects on hooks so as to fool those feeding fish in the river gave birth to the “art” of fly tying. If you are a novice, you can comfortably skip this step, at least for a while and simply purchase the flies you want or need. In time you will no doubt wish to start making (tying) your own.

The bigger problem, both for the Ancient Greeks and the modern newcomer is to find a way to “throw” these diminutive flies far enough to catch fish. That is the idea of fly casting, and there seems to be some sort of fear of it, that puts off numerous anglers from ever even trying, but in reality, it is simply another way of casting and fishing. Not unlike perhaps the difference between driving, what the Americans refer to as a “stick shift” and an automatic transmission vehicle. Just another way of achieving the same goal.

Now to start with, nobody came up with a better solution than having longer and longer rods, from which they might dangle their flies over the water. In Europe, at the time, rods were made from wood, usually Greenheart and they were heavy. The longer they got the heavier they were so there was a limit to how much of a rod a normally muscled individual could manage.

Interestingly in Japan the rods were made out of bamboo, a far lighter material and with that the length of the rods could be considerably greater and reach more distant fish without effort.

With the length of the rod being quite a severe limitation eventually the idea was born (and I have no idea by whom), that perhaps you could put the weight into the line rather than the lure (as is the case with almost all other forms of fishing and casting).

Over time the materials to manufacture weighted lines for fly casting have varied from horse hair to silk and on to modern plastics, but the only really important part is that now, with a weighted line, one could, with a different technique, cast near weightless flies some distance.

(Do bear in mind that weight and density are two different things, so that one can have a relatively heavy line that might still float if constructed to do so).  So, anyway, with the birth of the weighted line; fly casting was born. Back in Japan, with lighter and longer rods the need for weighted lines was less and the method of “Tenkara” became standard practice for “fly anglers”.

Tenkara Angler, there is no reel or rod guides, just the line tied to the end of the pole, that is very close to the original origins of fly fishing, before the invention of casting and special lines.

(Incidentally, Tenkara has seen a rise in popularity in recent years, the main difference being that the rods are long and light and the line is only attached to the tip of the rod, there are no guides or a reel in the setup, ).

Now the rub is that if the weight is in the line, and not at the end of it, you need a different means of “throwing it”. (Don’t ever use the word throw amongst fly anglers, they get upset about it, the correct term is “cast or casting”). That is the only real difference when it comes to fly fishing tackle, the gear is designed to cast the line and pull the fly along as a passenger, in most other forms of fishing the mass is at the end of the line and the line gets pulled along as the passenger. That’s it! The only REAL difference and this certainly shouldn’t be enough to put off any aspiring fly fisherman from starting out. If some ancient guy in a worm-stained toga can manage it then so can you!

It isn’t as though someone dreamed up a “more difficult” means of fishing just to annoy us all, but rather that a different technique is demanded by the mechanics of how fly-fishing gear works.

So, the real point here is that the mechanics are different to other forms of fishing simply because of the physics involved, but there is absolutely no reason for that to put anyone off fly fishing, don’t get hung up on it, if you can walk and chew gum you can learn to fly-cast.

Of course, as with any new skill, it is a huge advantage to get some proper tuition from a certified instructor as early as is practicable. Learning the correct technique from the outset will save a lot of frustration later on. There are several organisations which certify casting instructors in various parts of the world. The one I belong to: Fly Fisher’s International provide an on-line resource to find a casting instructor near you on the following link: https://www.flyfishersinternational.org/Get-Involved/Connect-with-FFI-Members/Casting-Instructors

Some additional fly casting posts on “The Fishing Gene Blog”:
https://paracaddis.wordpress.com/2015/09/27/casting-about-2/
https://paracaddis.wordpress.com/2015/12/09/more-casting-about/
https://paracaddis.wordpress.com/2016/05/17/casting-accuracy/