“Overlining” a fly rod refers to the practice of using a fly line that is rated higher than the designation on your fly rod. Eg using a 6wt fly line on a fly rod designated as a ‘5wt’.
Underlining a fly rod is the reverse I.e using a 5wt fly line on a fly rod designated by the manufacturer as a ‘6wt’ fly rod.
This all gets a little sketchy these days because:
There is no standard to label the intrinsic power of a fly rod. And many fly rod manufacturers produce fly rods that would normally be stiffer than would be a fair designation in their pursuit to sell “fast fly rods”. For some reason the perception is that faster is better and consumers go for this as being some sort of benefit.
It's important to know that overlining or underlining a fly rod will not change it’s intrinsic properties. It will, all things being equal, make it bend more or less for a given amount of line out the rod tip.
Overlining a fly rod:
Why you might wish to overline your fly rod.
Casting short distances in windy conditions
Picking up and turning over very large flies
Lots of roll casting in confined spaces / no backcast room
Loading (Bending) the rod with a short amount of line out the tip
You have a stupidly stiff fly rod that the manufacture has underrated in order to make it feel “fast”
Keep in mind that many fly lines are now over the AFFTA recommended weight for the specification - so in many cases you are already casting an “over-lined” fly rod by default
Underlining a fly rod:
All things being equal - a lighter line will deflect / bend the rod less for a given amount of line out.
Result in tighter loops
Allow a longer carry
Give a more delicate presentation than a heavier line.
If you look at the actual weight stated on fly line specifications above, you’ll see that many fly lines areheavier than the highest limit of the specification.
The problem then is that unless you’re aware of that when you buy the fly line, you might be overlining a fly rod that is already effectively overlined.
The AFFTA system, is not perfect, but if line manufacturers kept their products in line with the standard specificationsthere would at least be a “standard” and all our lives would be made much easier. Then, you could adjust up or down for your rod type without having to double-check that the specifications of the line matched the standard.
Our Glassline fly lines- produced for us by Scientific Anglers USA match the sweet spot for a given weight exactly. Epic Glassinefly lines - True to weight fly lines
Our fly rods are rated against the AFFTA standard for each line - and are, to the fullest extent possible - true to weigh. Epic Studio Built Fly Rods - True to Weight Fly Rods
BEARHAWK LIMITED EDITION FLY RODS The Bearhawk Limited Edition* line of fly rod building kits and fly rods are inspired by fishing trips in my friends Bearhawk airplane. We always get there fast and can land in a places where most planes simply can not go.
The slim beauty is one of the most popular fly fishing knots in use today. It is a great knot for connecting class tippets to shock tippets as well as tippet sections to butt sections. This knot is strong, easy to tie on the water, and has a very low profile.
It is the end of the fishing season in Patagonia Argentina. Two of my buddies, Marcos Hlace, Diego Soto and myself decided to fish for the mighty migratory trout at the upper Limay River, a must to at least once in a life time.