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Samson Ropes: one size does not fit all

Richard Tregoweth - Monday, November 07, 2011

The metaphorical ink has barely dried on the page since our 'Rope innovation required' blog of October 14 and Samson Ropes have launched the new 24-strand, 12.7mm Vortex climbing line onto the international market.

Sure Samson Vortex is not an access rope but it does offer some new innovation for a climbing line, specifically reduced weight and a very low elastic elongation relative to ABS.

Samson Vortex is modeled on the popular 24-strand, double braid, Polyester/Nylon Velocity family - Vortex even sports the same colors.

The differences lie in the ropes diameter (12.7mm), weight per 100m (11.3 kg) and elastic elongation which is 25-30% lower than both Velocity and Arbormaster (see graph below).

The elastic elongation figures can be a little confusing.

Stats are based on elongation at 10%, 20% and 30% of the ropes average break strength. ANSI Z133.1 1-2006 8.1.8 states "Maximum working elongation shall not exceed 7 percent at a load of 540 pounds (2.402 kN)." A low elongation percentage figure is considered better but this is a matter of personal preference.

As an example, the elastic elongation percentages for Velocity, Arbormaster and Vortex are the same: 3, 5, 6% elongation when tested against 10, 20 and 30% of Average Break Strength (ABS).

But there is a big difference between the ABS of each rope: Velocity 2700 kg, Arbormaster 2900 kg and Vortex 4000 kg which at 10% results in 270 kg, 290 kg and 400 kg respectively. The ANSI elastic elongation figures are rated on a common load application of 540 pounds (approximately 245 kg or 2.402 kN)

Vortex has a much higher average break strength (spliced) than the other two. Consequently, when the same load of 2.402 kN is applied, the elastic elongation for Vortex is lower, relative to Velocity and Arbormaster - a very low elongation of 1.4% in this instance (again, see graph below).

Samson Vortex is likely to appeal to climbers looking for a low bounce, larger diameter climbing line. The 12.7mm diameter makes the line easier on the hands; a feature sought after by older, heavier climbers.

In Treetools opinion, Vortex will be better suited to knot-based climbing configurations; the 12.7mm diameter being outside the operating range of many of the new mechanical devices.

Samson Climbing Lines

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