Its confusing enough for a normal salmon loving, scandi-style, 2hand European caster to have to come to grips with grains, but our fly-swinging friends across the Atlantic have come up with something else in the form of a skagit-line extension called a [skagit] cheater!
One of the original ideas behind Skagit casting was to maintain a constant ratio between the rod length and the length of the line body or head. A lot has been written about this “ratio”, some time back the experts were of the opinion that 4:1 was the ideal ratio, then 3.5:1 and 3:1 appeared on the scene. Now 2.2 – 2.5:1 seems to be in fashion. Independent of the current “ratio de jour” it is important that you find your happy ratio, this may be 4:1 or 3.5:1, 3.0:1 or even 2.5:1. Lets assume for the purpose of this example, that you feel comfortable with a ratio of 3:1 (its easier for me to work out as well – but that’s just a coincidence) . So based on this a 12 ft (oops feet, yes once again its easier for me to work it all out instead of having to convert to the metric system) rod would require 36 ft of line and a 15 ft rod will require 45 ft. If you keep to this ratio you will not have to adjust your casting stroke, independent of the length of rod you have in your hands.
If you like this ratio and you use a 12 ft rod, then you are going to need roughly 36 ft of line to feel comfortable. If your Skagit line has a head of 27 ft and you are using a 10 ft sink-tip (Txyz) adding the two together results in 37ft; so this means you do not require a cheater. If however you decide to fish with a a 14 ft rod then by applying the 3:1 ratio you would ideally require a total “line” length of roughly 42ft. Using the same head/tip set up as before the total line length is still only 37 ft, so, in order to keep the same stroke length you would need to add a 5 ft Cheater (27 + 5 + 10 = 42).
The whole idea is can be pretty confusing to a humble European skagit novice, but once the concept is grasped, it is very easy to understand and enables you to use a constant stroke length , independent of the length of rod and line/tip used…
… you may prefer of course choose to ignore the whole thing and just cope with varying stroke lengths like we do.