I have a couple of reels that have line on it and can't tell what weight rod it's for !!!! Is their a way to tell if their is nothing on the reel ?

Weigh the 1st 30ft of tip section on a scale that weighs in grams (or oz., but weighing is grams is easier) (small kitchen scale). Fly line weights (in grains) are: 3wt=100+/-6=(about) 6.48oz.
4wt=120+/-6=(about) 7.78oz.
5wt=140+/-6=(about) 9.07oz.
6wt=160+/-8=(about) 10.42oz.
7wt=185+/-8=(about) 11.99oz.
8wt=210+/-8=(about) 13.61z.
Covert grains to grams. The following web site provides a calculator to make the conversion easy:
[www.itinscales.com]

You can determine the weight class by the weight of the line, thats how its determined, I think in grams. (just the fly line)

Those ounce conversions don't sound right. A 4wt line only weighs about 1/4ounce over the first 30 feet and you are showing 7.78 ounce. Could you go over these one more time and make sure they are accurate? Thanks.

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The question of determining a lines weight class by weighing it some how comes up often. In the description of the AFTMA system, you'll see something like "--the weight of the first 30 feet, excluding taper--" The main problem is that the line weight is "Calculated" by the maker given the density or weight of their particular material. To try and weigh 30 feet of a line without the rest of it affecting the scale is well neigh impossible. I spent one whole day with a scale accurate to 1/10 grain trying to devise a way to do it! If some one has found a way to get the job done, I would be very interested in how it works. There are 437.5 grains per ounce, avourdupois BTW.

According to my redimentary math, 120 (weight for 30 feet of 4 weight line above) by 16 and then divided by 437.5 comes out to roughly 4. That's 4/16th or 1/4 ounce, which would be just about right for a 4 weight and about what corresponding 4 weight rods are rated to throw.

For those of you who need a quick way to correspond fly blanks to spinning blanks, keep in mind that if you use the line weight designation as the numerator, and 16 as your denominator, you will arrive at a fairly close means of what the rods are rated to throw, in ounces. This is pretty accurate up to about an 8 weight or so.

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