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Dyneema net edging

This is the first row of continuous half-hitches to secure the net to the boltrope.

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Comment by kim whitmyre on May 31, 2012 at 11:09pm: The Net Systems web site does say this:"Ultra Cross netting is available in high-tenacity polyethylene, Dyneema®, and nylon." I have no idea of the cost of the polyethylene or nylon knotless net unfortunately.

Comment by Hans Hammig on June 11, 2012 at 1:35pm: This is very interesting. I just followed the latest rope tests comparing knots and bends in dyneema. braided and 'normal' polyester. Only splices deliver a good strength. Otherwise there is nothing to connect dyneema with a strength of more than about 30%. Knotless connections amount to a bend, which is notoriously weak. Knot strength in polyester is much higher (but only with the correct knot). In the end the result with polyester is the same as with dyneema, as the weakest link is in the know or bend. As I am lashing a lot on Phefo, I am faced with the same dilemma. As an example. If you have a 3 ton dyneema rope, the knot will break at 1 ton, and the connection should not be exposed to more than 200 - 300 kg load. On the other hand, a proper splice will hold 2,4 tons, but it might be difficult to apply. If you loop 2 splices together, then you are again down to a breaking strength of 1 ton. So what is the solution?

Comment by kim whitmyre on June 11, 2012 at 2:39pm: Hans, here is a comment from Colligo Synthetic Systems :

"...meet Hampidjan's recomended minimum 5/1 bending ratio for Dynex Dux. This is essential for long term durabilty of Heat Stretched, Dynex Dux, UHMWPE line as the work hardening makes the line much stiffer and tight bending radii cause compressive stresses that weaken the line considerably."

The regular, that is, non-heat stretched dyneema, has much less of a tendency to work-harden than dux, but the 5:1 radius guidelines will insure the strength of the line is maintained.

With dyneema or dux, the strength of the line is normally so much stronger than anything else that, with a little care, you should be fine. The line is very slippery, so you do have to use different stopper knots:

stopper knot for dyneema

And here is a good lashing method:

lashing using dyneema

Comment by kim whitmyre on June 11, 2012 at 2:41pm: The knotless connections in the netting are actually a form of crocheting, which allows the individual strands to remain straight.

Comment by Hans Hammig on June 13, 2012 at 10:44am: Thanks, Kim. I have saved the file with the 'double-eight' stopper knot. You are a star!

Comment by kim whitmyre on June 13, 2012 at 11:01am: Just a geeky gearhead, actually... ;-)

Comment by Roger on December 19, 2012 at 2:31pm: Hi Kim,

How is your new net construction holding up to use? My front net is failing and I have to do something soon.

Roger

Comment by kim whitmyre on December 19, 2012 at 5:32pm: Roger,

The net is holding up very well; when my front tramp ever goes (no signs as of yet!), I'll use the dyneema netting for it. The netting is comfortable to lay on, and easy to walk on. Recommended!

Comment by Roger on December 20, 2012 at 11:51am: Hi Kim,

My front net gets a real beating with jib changes and anchoring etc. Do you think that your stitching method will hold up to the heavier use on the front too? I'm planning on copying your method, but using (cheaper) nylon knotless netting.