The above chart shows the various line profiles and the names for each section of the line.
No. 1 Shows the sectional terms for each section.
No. 2 This would be the Weight Forward Line.
No. 3 This would be the Double Tapered Line.
No. 4 This would be the Shooting Head Taper.
No. 5 This would be the Level Line.
Level Line
The Level line designation simply means that the fly line has the same diameter throughout its total length. This line is the least expensive to manufacture and is still around but only because rod manufacturers will preload these lines onto the reels of rod and reel sets that are sold as fly rod combos. The only advantage to these lines is the economic value to the manufacturer. These lines have very poor casting characteristics and are not recommended for either long casts or delicate presentations. The long and short of it is, don't even think of using these lines.
Double Taper
The Double Taper line is center leveled and tapers out to each end equally. The advantage of this type of line is the fact that it can be reversed when one end of the line becomes worn or damaged. This line has much better casting characteristics then the Level line.
Triangle Taper
The Triangle Taper line, marketed by Wulff, has a longer distance of taper. It casts very well, rolls out smoothly and these qualities make it not only a wonderful dry line but also a much better line for Roll-Casting. There is also the added benefit of reduced resistance through the various guides for longer casts.
Weight Forward
The Weight Forward line places most of its weight in the first 30 feet of line. This line then tapers down to a fine running line, which travels thru the rods guides very easily. Because of less resistance during the feeding cast, this line can gain more momentum during the cast. The Weight Forward line allows for longer distances and more delicate presentations then either the Double Taper or the Level line. Because of progressively better weight forward profiles plus better and less resistant coatings on the line itself, the Weight Forward line has become the fly fishing standard and placed the Double Tapered line on the back shelf.
There are also several variations on the Weight Forward line. The Bass Bug Taper and the Salt Water Taper have advanced the majority of the lines weight even further towards the front and this advancement allows the heavier imitations to be cast further but still allow for a soft presentation.
The Bass Bug line carries the weight of the line to the front but the Salt Water Taper or Shooting Head line is only some 30 feet in length attached to a small diameter monofilament shooting line, and will cast much further than any other taper because of the reduced resistance through the rods guides. Weight Forward lines (WF) come in both the floating profile (WFF) and the sinking profile (WFS).
Bass Bug Taper (BBT) lines are used to cast large plugs and lures and is also a Weight Forward profile (WF).
Salt-Water Taper (SWT) lines are used to launch those large ocean flies in the heavy surf or offshore. These are also a Weight Forward profile (WF).
The front section of the Fly Line is referred to as the Head. The area behind the Head is called the Body and the rest of the trailing Fly Line is referred to as the Running Line.
Floating Lines
The Floating line has become the basic tool of most fly anglers. This line allows the techniques employed by both the Dry Fly enthusiast and the Wet Fly angler, as well. This line is both the easiest to fish and the most enjoyable to cast. The Floating Line is clearly visible at all times, including the Leader section, Tippet and finally even the fly. But the most enjoyable event that can be clearly seen is the strike itself. I can even now, remember a cool early evening on the famous Nesowadnehunk Lake (The Trout Factory), just northwest of Mt. Katahdin and I was using an Adams Dry, which was taken by a beautiful native square-tail. It was the first time that I witnessed my fly taken by a fish and will never forget the thrill, as long as a live.
Sinking Lines
There are some situations that require going deep to get your imitation to the fish and the only line that will get the fly there is a sinking line. Whenever the fish are feeding below the surface or during the real warm days of summer, when the fish will retreat to the cooler temperatures of the deeper pools is when you will need this line. The only other application is when your fishing a lake or pond.
These Sinking Lines come in a range of different line densities, which are classified as Slow Sink, Intermediate Sink, Fast Sink, and even Extra Fast Sink. The choice depends on how deep and/or how fast do you want to get the fly there. The rate in which the line will sink is usually rated in inches or feet per second and is simply cast out, allowing the angler to count off the time that will allow the fly to reach a predetermined depth and then start the retrieval process.
Combination Lines
This line is nothing more than two lines connected together. The main section of the line will be a Floating Profile and attached to the front of the line will be a section of Sinking Line. This line is frequently called a Sink Tip (F/T). The advantage of this line is to be able to present the fly below the water surface but still being able to watch the rest of the line on the waters surface.
These lines are easier to pick up from the waters surface into the Backcast, and much easier to mend the line while it's on the surface. (Mending is changing the position of the surface line in order to maintain a drag-free drift).
These sinking tips, also come in various lengths, or sinking portions. Your selection will, once again, depend on how fast and how deep you want the fly to get there. The maximum sink rate is reached only in none moving water, or when the line is moving at the same velocity of the current. Once the retrieval of line starts, the line will cause the fly to rise towards the surface.
One of the best techniques used today, is to have a loop connection placed on the end of your Floating Line and then to have similar loop connections attached to each of your Sinking Tips and all of your Leaders. This way you can have the freedom to fish only the Floating Line or you can attach a Sinking Line on at will, to cover the deeper applications, when required.
Selecting Your Fly-Line
When you purchase a fly line, it should be done on the basis of fishing to be done, the sizes and types of flies to be used and the fly rod manufacturers suggested weight range for that particular rod.
Remember that, the lighter the line is the smaller the fly, will fly! Also, the larger the line, the larger the fly, it will drag behind.
3-5 Weight Lines will give the fly a softer presentation, which will not scare the fish. This line weight has much less wind resistance and carries the real small sized flies well. The typical fly size for this line would be sizes #22 down to #28
6-7 Weight Lines are the most common and well suited to the medium fish and probably the main choice for most anglers going after the brook trout, salmon, both small and large mouth bass, as well as, smaller salt water stripers and blues. This line is used for the large wet flies, streamers and the larger nymphs.
8-9 Weight Lines are for the really large lake trout, large salmon, steelhead and larger bass, both fresh and salt-water varieties. These line will cast the large wind-resistant flies and bass bugs very nicely.
10-15 Weight Line are for the large salt water sport fish such as, Tarpon, Barracuda, Atlantic Salmon and so on, keep in mind these line carry very large streamers and plugs and this type of fishing requires long.