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Topic Date User

Old but unused rope - still okay or not? 31-Oct-2003 At 9:01:51 AM Mike

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As I understand it, after five or six years, even a rope that never gets used will have lost some elasticity, simply due to age. You might not want to take a serious leader fall on it, but it should be fine for abseil/top rope.

Here's a little cut and paste to stir up some conversion....

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Conference on Nylon and Ropes for Mountaineering and Caving
21.10.2002 10:00
The Club Italian Alpine Club under the auspices of the UIAA organized this conference in Turin. While it was known that wet ropes lose much of their capacity, the rapid degradation of ropes in abseiling and top roping is surprising.

A SUMMARY OF THE CONFERENCE ON NYLON AND ROPES, TURIN, MARCH 8/9, 2002

Several scientific papers were presented, including mathematical modeling of belay techniques and analytical models for the analysis of textile ropes. Water absorption in polymers is much better understood now than over 30 years ago, when tests established that a wet rope loses much of its dynamic performance. Today it is known that water causes the nylon to plasticize, drastically changing its mechanical and physical properties.

5. When to retire a rope; a study of rope wear:
- it is hardly any news that the principal factors of rope wear are the combined effects of rubbing against rock, mechanical reduction (rappelling and belaying devices), dust and microcrystals that penetrate the sheath and the number of meters climbed (not the time used),
- the enemy of rope wear is friction - most intense in abseiling and top roping, made worse by dirt, and the inevitable rubbing against rock,
- some abseiling devices produce much more wear damage than others,
- after only 50 descents with a figure-eight, the dynamic resistance of a rope is reduced by one third (number of drops). The descents were undertaken with extreme care - slowly and without impact,
- rappelling with a Robot (a multi-use device manufactured by Kong) does not appear to compromise the dynamic resistance of the rope. The device functions like a carabiner brake,
- not surprisingly rope wear is much more severe on granite than on limestone,
- rope degradation is approximately proportional to the number of broken textile yarns of the sheath,
- current work confirms previously published information. After climbing approximately 5000 meters, the dynamic resistance of the rope is reduced to half and after an additional 6000 meters it is down to 30 % (UIAA Bulletin # 146, June 1994, in German),
- see also The Journal of the UIAA #3, 2000, pp. 12 - 13, available on the Internet under http://journal.uiaa.ch/edition.asp?id=114.