This dyneema lines, any good?

Could you enlighten us how to do it properly, please ? :)


If you imagine lines like knitted, that's how they are. It is the last few meters when you roll your lines what matters. Sometimes just hell.

My new 5 and 4 lines kite never tangles like this...If my doing is the same, than must be the lines or swivel.

So loosing 15min to untangle for 20 sessions = 5 hours lost time:(((((

OK, "the truth" speaks some, Spectra and Dyneema are HMPE, the same thing with different brand names and manufacturers between US and EU markets. Few corrections...

There's a difference in the size of spinnerets used to make the individual fibres, Dyneema (16um+/-5) is a much smaller cross section that Spectra (spun to order but generally 20-60um). This has pluses and minuses; basically Dyneema is slightly stronger and creeps less, Spectra is slightly more durable. At the end of the day,
1) Very few people realise what the difference is and most claims of them being different or the same are often ill informed
2) It'll be flip a coin if you hooked the same size Dyneema and Spectra together and pulled until it broke.
3) Use the terms interchangeably because only a serious rope nut is really going to know what the difference is.
4) The only real way to know what you're getting is to trace back the rope source.

Climbers don't use HMPEs because you don't want to take a 10m fall and be stopped instantly, you want a nice slow deceleration so they use extremely high stretch rope. Abseilers don't use it because it does not play well with heat (140 upwards is game over but you will see annealed HMPE, taken up to about 135 degrees and slowly cooled back down, makes the molecules bond together for additional strength but no longer as pliable).

Creep is a function of the fibre itself and as well as braid. The creep is occurring across molecular chains because they're imbalanced. The closer you are to breaking strain in terms of your load the faster you creep is going to be. Going from 15% to 30% of breaking strain results in a 6 times increase in creep rate. Creep is actually a really good way of avoiding broken lines, about 8-10% creep from purchase and it's time to throw them away (those are SK60 type numbers the worst case I think you'd see).

HMPE isn't just HMPE, there are different grades. They will have a designation which describes the quality of the fibre used. SK60 Dyneema is about Spectra 900, SK75 is around 1000, SK90 is the latest and greatest. The different designations are simply a function of improvement in manufacturing process producing better creep/strength characteristics.

There's a number of problems with the way kiters use HMPE...
1) Insanely low breaking strength v's working load, we all want the lowest drag possible meaning thinnest rope, meaning lowest break strength.
2) Connection system, the sheath and stitch method just makes a rigger cry, it completely messes with the fibre loading, and I suggest thats where a lot of the creep comes from.
3) Block diameter, the rope needs about 20 times it's diameter to retain something approaching full breaking strain otherwise fibres get imbalanced loading. Putting 3mm HMPE through a 20mm block results in about 75% of breaking strain.

The reason HMPE is used? Strongest thing around (only one fibre stronger, Zylon a PBO, and that's completely unstable in UV, completely useless with abrasion and sinks), floats, UV resistant, chemically inert.

To the OPs question. By "monofilament wound" we instantly know that it's Spectra because they're using a insanely large diameter fibre. What doesn't make sense is this a weaker rope (by breaking strain) and can only assume the plan was to try and eliminate creep. Either way Cabrinha recalled them at the end of '10 because they couldn't control creep and went back to a normal braided line. The only reason I could see for this to be easier to manage is less fibres = less things to catch on.

Hope that helps.

NB All of this is written with very limited kite experience.