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General Climbing Discussion

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Cordalettes 26-Sep-2003 At 2:27:15 PM dodgy

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I have a Gemini cord version 5.5mm, it is a combination of spectra and kevlar, the advantage being a higher melting point than spectra alone (spectra softens at 100C and melts at 147C). Gemini was made by Black Diamond but is no longer produced. Spectra/Gemini is lighter and more compact than nylon for more strength, but a bloody sight dearer. If you want spectra at the right price try yachting shops, it's about half the price of (us) outdoor retailers!
5.5mm Spectra or Gemini has a breaking strain of about 1800Kg from memory, 7mm accessory cord is about 1000Kg, so doubled we are looking at 3600 and 2000Kg respectively. A 10.5mm climbing rope is about 1800Kg (from memory) so the anchor is stronger, but the strongest cams (larger camalots) are about 16Kn anyway, and a nut or hex only 2 to 12Kn in an ideal (one that can't break) placement, what is the rock rated at anyway? In short they are plenty strong enough and there are more variables than this anyway.
Remember it is critical to use a TRIPLE fishermans knot in spectra because it is slippery...