I recently tested the knots I have been using for many, many years. I discovered that the knots Ive been using were not as strong as they could have been. The three knots I tested were the three knots that I use most frequently: the improved clinch, the blood knot and the duncan loop. For my test I used 5X Umpua tippet material for the improved clinch and duncan loop knots. I used 4X and 5X Umqua for the blood knot. My goal was to determine the number of turns for each knot that maximized the breaking strength. For the improved clinch knot and duncan loop knots I would tie a fly (Tiemco 3769, #16) at one end with, say, 4 turns and a similar fly at the other end with 5 turns. I would then pull the flies apart to see which knot broke first. For the blood knot I would tie one knot with 5X at one end of the 4X and another knot with 5X at the other end; I would then pull the line apart to see which knot broke first. I would repeat each test several times and systematically compare knots with different numbers of turns at each end. By doing so I determined the number of turns for each knot that produced the strongest knot. Here are my results:
Using Umqua 5X, with flies tied on a Tiemco 3769 #16 hook:
The strongest Improved Clinch knot was tied with 4 ˝ turns
The strongest Duncan Loop knot was tied with 3 turns
Tying Umqua 4X to Umqua 5X:
The strongest Blood knot was tied with 4-4 turns (i.e. 4 turns on each side of the knot)
Notes:
1) The turns required for the strongest knot can vary by brand of tippet material. For example, Rio tippet has a slicker finish than Umqua. The little testing I did with Rio tippet suggested that its strongest knots may require more turns than Umqua.
2) Hook size and diameter can influence knot strength. Remember that dry fly hooks are made with fine wire while many nymph hooks are made with 2X heavy wire. The thickness of the wire can influence how many turns are needed in a knot for maximum strength.
3) My tests were not scientific in any way. There were done at the kitchen table. I did try to be "fair", however. For example, I would reverse the flies after each test in order to ensure that an imperfection in a hook was not causing a weak knot. Also, obvious bad knots were rejected before testing.
My suggestion: Use my results as a starting point and do your own simple tests. Use your favorite tippet brand and the fly sizes that you use most frequently. In this way you can satisfy yourself with what knots work best for you. In all honesty, I wish I had done this testing a long time ago.
. Q. were you wetting down the line prior to dressing the knot?.and im willing to bet when using the 5xflouro tippet and tying the blood knot with 4 turns did it have a curve at the end of the break?meaning it broke in the actual knot and not at the hook eye?and if that was the case the knot was actually slipping out of itself priror to breaking. I have found that when tying 5x flouro in a blood knot after wetting the knot priror to dressing that 6 turns or wraps is most effective. anything less you get the curved or bent end of the break.signifying that the knot slipped befor it broke. I only say this because I love knots and have taken a few classes on them,Mandated classes of course. but I instantly fell in love with knots and how they react under stress.
My tests were done with mono, not fluorocarbon tippet. I don't use flourocarbon tippet at Putah so I didn't run my tests with it. That's the reason why I suggested that each person run his own tests. Every tippet tests differently. I did wet each knot before drawing it tight.
You may be right about the fluoro. I tend to use a lot of tippet material at Putah since I try to fish it every week. Thus, at $13-$15 a spool, it would get a bit expensive. I rationalize by telling myself that the water in Putah is a bit off-color so fluoro tippet isn't necessary and, generally, I have had pretty good success. Eventually, though, I will probably break down and start using the stuff at Putah. When I do make the switch, I will retest my knots again. Thanks for the input.
I never use flouro. simply because i just burn through spools of 4, 5, and 6x tippet material likes its going out of style. It would be too expensive and i beleive the cost is not justified, Mono has worked just fine for me.
Shon, i think your right that theres not that much of a difference between mono and flouro (other than the sinking rate), assuming the line size is the same for both. For example, someone fishing 5x fluoro would probably do just as well as someone with 5x mono. However, the real difference is the freedom to down size your tippit and keep the same success rate you would have had with the lighter mono. For example, instead of fishing 5x mono, i can throw 4 or 3x fluoro. This is a huge advantage, your line sinks just as fast as a higher tipit, its just as less visible as a higher tippit, and its stronger than a higher tippit. Also, I think if you try fluoro you will find that you dont go through as many spools of tippit as you would using mono, simply put, its much stronger, and more durable.
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all of a man's addictions end and begin when he learns to fly fish
Drifter, you make a good point about being able to use heavier tippet and still have the same success rate. When my supply of 5X starts getting low and the stream starts to clear up, I will buy some 4X flouro and try it. But, as I said before, I will have to do some more knot testing to find out how to best tie the three knots I use the most. There's no use in increasing the strength of the tippet if the knots are not as strong as they should be.
