O.K., since I make my Living at Flyfishing (hence my moniker is "flyjunkie") I will explain some basics of Tippet/Leader nomenclature..
Monofilament & Fluorocarbon Tippet is measured not only in breaking strength but diameter. the Diameters are given soo that Anglers who build their own tapered leaders can match diameters closely as they build their leaders. all top quality spools of tippet/leader material will contain both breaking strength and Diameter measurements on the label.
There is not, unfortunately, any standardization of Diameter verses Breaking strength.. in fact as the technology improves in exuding Mono or Fluorocarbon. we've seen a reduction in Diameter verses breaking strength.
Monofilament breaks down / rots at a quicker rate then fluorocarbon does.. average "shelf Life" is 11/2 ~ 2 years from date of purchase.. this Breaking down / rotting is the result of exposure to UV rays, oxygen, gasoline, dirt, etc... rotten Monofilament looks Flat, Opaque, remains coiled and feels dry and rough, it also snaps with little or no pressure. Fluorocarbon breaks down/rots a much slower rate.. lasting up to 10 years..
Fluorocarbon also will be of a thinner diameter per breaking strength then Monofilament...
Also, the stated breaking strength / Pound test is just a estimate, often lower quality lines break at less then stated pound test and quality lines often break at a higher then stated pound test. Exception is when the line is stated as meeting IGFA standards.. the I.G.F.A. is the International Gamefish Fishing Association. they keep the World records of largest Fish caught, Line class records as well.. their rules state that a Line in a particular Line class must actually break at the stated amount.. soo any line that claims it is IGFA certified will break at the stated pound test breaking strength, not below and not above the stated breaking strength..
don't know if any of this is helpful to Model building, but I think it might be....

DEAN ~~~
