Fly reels, or fly casting reels, with a few exceptions, are really little more than line-storage devices. In use, a fly fishermen strips line off the reel with one hand while casting and manipulating the rod with the other. Slack line is picked up by rotating the reel spool. Even today, the vast majority of fly reels are manually-operated, single-action reels of rather simple construction, with a simple click-pawl drag system. However, in recent years, more advanced fly reels have been developed for larger fish and more demanding conditions. These newer reels feature disc-type mechanical, adjustable drag systems to permit the use of lighter leaders and tippets, or to successfully capture fish that undertake long, powerful runs. Many newer fly reels have large-arbors to increase the speed of the retrieve and to improve drag performance during long runs. In order to prevent corrosion, saltwater fly reels often use aluminum frames and spools or stainless steel components with sealed bearing and drive mechanisms.
Some reels with simple click drags are designed to be "palmed" when a fish runs with the line. Palming allows the angler to add additional drag with a light touch of the palm to the rim of the reel. On some reels, palming is difficult or impossible because the spool is fully skirted. With such reels, the only drag that an angler can apply to the line is with one or more fingers directly pinching the line.
The fly line can be retrieved using either hand. Most modern fly reels can be converted to or from left-hand or right-hand retrieve. Many fly anglers who have come to the sport after spending some years as spin casting anglers are more comfortable with a left-hand retrieve. Right handed "big game" fishers may find the right hand retrieve more efficient. In either case, modern large-arbor reels can be retrieved with fair efficiency using either hand to retrieve.
Fly reels are often rated for a specific weight and type of fly line in combination with a specific strength and length of backing. For example, the documentation supplied with a reel may state that the reel can take 150 yards of 50 pound-test backing and 30 yards of fly line. An angler should be able to "load" the reel with the specified length of line and backing and still have sufficient room between the line and the spool's edge. As well, many modern reels are designed to take interchangeable spools. Such spools can be quickly switched, thus allowing an angler to change the type of line in a matter of minutes.
A few knots have become more or less standard for attaching the various parts of the fly lines and backing, etc, together. A detailed discussion of most of these knots is available in any good book on fly fishing. Some of the knots that are in most every fly angler's arsenal are: the improved clinch knot which is commonly used to attach the fly to the leader, the overhand slip knot or arbor knot which is used to attach the backing to the spool, the albright knot which can be used to attach the fly line to the backing. Often, a loop is added to the end of the fly line using a braided loop or by attaching a monofilament loop to the fly line using a nail or tube knot. A loop can be added to monofilament line using a double surgeon's knot or a perfection loop.[4] A loop can be put in fly line backing using a bimini twist.[5] Finally, a tapered leader can be attached to the fly line using a loop to loop connection. The use of loop to loop connections between the fly line and the leader provides a quick and convenient way to change or replace a tapered leader. Many commercially-produced tapered leaders come with a pre-tied loop connection.
Some traditionalists create their own tapered leaders using progressively smaller-diameter lengths of monofilament line tied together with the blood or barrel knot.
References
Rosenbauer, Tom, The Orvis Fly Fishing Guide, The Lyons Press, Connecticut, pp.41-43, 2007
Flycatcher, www.flycatcherinc.com/flywiki/index.php?title=Rigging
