May I recommend using Kevlar rather than Spectra / Dyneema for pull-pull systems. Although Spectra / Dyneema (different brand names for the same fibre) has a slightly higher strength to weight ratio than Kevlar it tends to 'creep' under load, causing loss of tension. That is why on some super high-performance unlimited budget dinghies you'll find Kevlar used on the forestay and shrouds, because they are always under tension, and Spectra for the trapeze wires as they are only temporarily under load. Ths is probably also why we don't see Spectra used anymore in composite layups. On the other hand, Spectra displays better fatigue properties than Kevlar. In tests on rock-climbing equipment it was found that Spectra lasted longer in a test where a rope emerging through a hole in a piece of equipment was repeatedly bent 90 deg. the one way, then the other. I forget the exact results,but it must have been thousands of cycles. Braided Kevlar line in several thicknesses is available from fresh-water fishing stores. The whole point may be moot, depending on how close to the load limit of the fibre it has been tensioned. Regards Richard Knott Bell Equipment Co. South Africa Wheeled Loader Marketing, Specials & Aftersales Support +27 (35) 907 9325 (ph) +27 (35) 907 9611 (fax) +27 (0) 82 775 8061 (mobile) ********************************************************************** This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error please notify the system manager. This footnote also confirms that this email message has been swept by MIMEsweeper for the presence of computer viruses. www.bell.co.za ********************************************************************** RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]
