Bombproof

Nobody writes about backing, and it's more important than you think. For beginners, backing is the dacron or synthetic line that lies between the fly line and spool. It has two functions: 1) to give you line in case a big or powerful fish runs out further than the length of the fly line, and 2) it allows you a faster rate of retrieve by making effective spool diameter larger. No one pays any attention to backing, and they should.

The first problem you face when choosing backing is "how much, and what strength"? This is sort of done for you in a general way in that a lot of reel manufacturers have published information on their web sites or in the reel booklet that will tell you about what the reel can hold. Most of these estimates are inexact in the sense that your results may vary, and if it is a large-arbor reel the manufacturer is lying through their teeth. I worked in a fly department at a sporting goods store, and it was a constant joke. Large arbor reels would have about half the advertised backing capacity.

First, let's talk about strength. Most backing sold today is either 20 lb. or 30 lb. test dacron. It comes in colors. Stick with white, it never bleeds color onto your fly line. The choice is obvious: it's a tradeoff between capacity and strength. You can fit more of the stuff on your spool if you go lighter. I am a biased proponent of the heavier and less of it school. This is a bias because most of my fishing is in freshwater. I rarely have a fish that runs into the backing, and when they do it is generally a salmon or steelhead in a river where the next bend is much closer than 100 yards away. So I have that much line out I am hosed anyway. In that case the 30 lb. test is easier to handle and I think that it increases the odds of getting my fly line back if the fish gets into the wood and I have to put the pressure on. The other extreme is saltwater bonefish flats. My experience with them is limited, but they make you feel like your fly has hooked an F-18 Hornet on a carrier deck and the little dancing guy next to the catapault has just done the launch gesture. There, they can and will spool you and the 20 lb. is preferable. The problem is based on the fact that I read that most fly lines have about a 25 lb. breaking strength. So thirty is better if you have the capacity.

There is a foolproof way of installing backing. Have they fly shop do it and let them deal with getting the right amount on the spool. If the guy has to cut off thirty yards, that's their problem. The only foolproof way of doing it yourself is to wind the fly line on the reel first, attach the backing, and then wind backing on over the line until the reel is filled. Then pull it all out and wind the backing on first. Filled is when you still have enough room to crank the reel without the fly line rubbing on the reel pillars. One thing to note- if you have multiple fly lines for that reel and no extra spools (my situation still) set it up with the heaviest line. It is surprising how much more space a WF-8-F line will need compared with even a 7 weight. And double taper lines are way thicker still. That way all your lines will fit without rubbing.

There are lighter and heavier strengths of backing. Gel-spun is very strong but thin for its strength. It's pretty specialized stuff and you see it mostly on big saltwater reels used for monstrous fish like marlin. There, every yard they can pack on counts. Gel spun is thin and much more likely to cut you so I don't use it. But I don't fish for marlin. At least not yet. One sort-of-forgotten backing is 12 lb. dacron. Joe Brooks (a famous fly fishing writer and columnist) recommended it for light freshwater fishing. I can't believe it isn't more popular because it is the perfect way to get a useful amount of backing on 1 through 4 weight reels. But you don't see it much in the catalogs, maybe because modern reel designs have smaller arbors. But it is worth considering.

One of the most overlooked bugaboos in fly fishing is the fly line to backing connection. There are a bunch of ways to do it, but whatever method you choose it needs to be smooth and strong. I think the most traditional connection is a nail knot, followed in popularity by a loop-to-loop connection. These are great, but you need to be sure that your knots slide though the guides and tip-top smoothly. If they don't, you face a broken tippet (sad), lost fly line (sadder), or a popped guide (end of fishing unless you have a backup rod).

I have my own system, and I have never seen it used by anyone else. This one has been tested on Chinook salmon on Michigan's Muskegon River, and it has never failed. On that river, you will see your backing more times in one day than you will in several years of fishing anywhere else.

I start with a nail knot and attach the backing to the fly line. I leave a very long tag end, about two feet. I then go up about 6 inches and put in a second nail knot. Then, I do it again. The end result looks weird- a series of nail knots connected by 6 inch lengths of dacron that are sort of loopy. It actually looks stupid until you watch it go out the guides. It rides smoothly, and the fly line stretches it tight. It is secure, and acts as a shock absorber at that critical connection.

At this point, you are thinking "that sounds reasonable, but what about changing fly lines?" Well the answer is simple and only slightly out of the box. Cut the dacron about 5 feet from the fly line, and put your loop to loop connections in the dacron. Loop to loop? I make the loops using a double surgeon's knot. Yes, I can tie a bimini twist, but I would argue that a well tied surgeon's knot is better than a badly tied bimini any day, and the strength difference is not worth worrying about. This setup does look silly, but nobody sees it unless there is a big fish thrashing about and they are looking at that and not your rigging. And it is far sillier to be seen chasing fly lines down the river.