Tippet selection

[Ziggy]

This is useful information - especially the "3 times rule" coupled with the "4 times rule"


From http://www.activeangler.com/flyfishing-articles/macnair-tippets1.shtml
To help you in the decision-making process of matching  tippet to fly, a couple of aides are available. But before going further, nothing  in fly fishing is absolute except for the AFTMA standards. Any  "how-to-do-it" guide is just that -- a guide. Since I believe  something is better than nothing, try the 4-Rule.
 The 4-Rule: The  4-Rule works this way: let’s say the fly you’ve selected is a #12 Royal  Coachman. To apply the 4-Rule to tippet selection, divide 12 (the size of the  fly hook) by 4. The product, 3, suggests the right tippet to use is 3X. It’s  the same thing as saying, "tie a #12 dry fly to a 3X tippet." Don’t,  however, become confused. If logic suggests a 5X tippet is bigger or heavier  than a 3X tippet, you are dead wrong! The larger the "X" number, the  smaller the tippet. If you remember my tongue-in-cheek story about Hermann  Smuck and the giant trout, recall that Herm’s #64 Black Wasp was attached to a  "gossamer" leader. Apply the 4-Rule and his tippet is 16X.  Unfortunately, a 16X is not for us common folk. It doesn’t exist! Most fly  fishers will never use anything with a number above 6X. I can barely see a #24  fly, much less thread a tippet through the hook’s eye. Even when I succeed, I  need a magnifying glass to tie it off.
 One other thought,  what works going one way is apt to go the other when the lanes are reversed. If  you happen to have a 3X tippet on the end of your leader and wonder what size  fly might be the best, apply the 4-Rule: multiply 3, the tippet size, by 4. The  suggested fly size is a #12.
 You should understand  that the 4-Rule is highly criticized by a number of fly fishers. Many prefer  the 3-Rule. It works the same way. For that matter, you might want to use both  -- the 4-Rule for bulky flies and the 3-Rule for slender flies. Whichever you  prefer, be aware the numbers will not always come out even. When you apply the  4-Rule to a #10 fly, don’t expect to tie-on a 2.5X tippet. Half-sizes don’t  exist! What to do? If the fly is slender, go with a 3X; if it’s bulky try a 2X.  The odds are, one of the two will properly tip over the fly before it settles  to the water.
 
From http://www.orvis.com/intro.aspx?subject=2202
Most tippet sizes will support three or four fly sizes  before they either get too stiff for a lifelike presentation or too thin to  straighten a fly. In general, choose the heavier size if the water is dirty or  turbulent, choose the finer size if the water is very clear and the fish are  spooky. For average conditions choose the middle size.
 

Tippet Size	Tippet Diameter	Fly sizes:
8X	.003"	22, 24, 26, 28
7X	.004"	18, 20, 22, 24
6X	.005"	16, 18, 20, 22
5X	.006"	14, 16, 18
4X	.007"	12, 14, 16
3X	.008"	6, 8, 10
2X	.009"	4, 6, 8
1X	.010"	2, 4, 6
0X	.011"	1/0, 2, 4

[WalkersKiller]

Interesting stuff! Will mark this as a sticky, normally use 6x or 7x...

[bassbug]

very helpfull Ziggy, still holds true today.
i would like to add a very important tip for tippet length, for me it is imperitve that i have a drag free drift when dry flying, once the tippet thickness is established the length will always be the next step. once you have a length of tippet on the leader with fly, test it before fishing. a few short cast will show if the fly lands correctly and with the tell tale "s" shapes on the tippet length, if not adjust by lengthening or shortening the tippet to compensate for the density of the fly.
ps - if it's too much, it's easier to ignore this biscuit