- Kevlar, What is it?
- Preparing the Ends of Kevlar Rope
Kevlar, what is it?
Kevlar is the registered trademark for a para-aramid synthetic fiber, related to other aramids such as Nomex and Technora. Developed at DuPont in 1965, this high strength material was first commercially used in the early 1970s as a replacement for steel in racing tires. Typically it is spun into ropes or fabric sheets that can be used as such or as an ingredient in composite material components.
IN PLAIN TEXT, for Amateur Radio Purposes: Kevlar is a very strong synthetic rope which does not stretch. Kevlar itselv deteriorates in the presence of Ultra-Violet light and must be protected. A thin Dacron cover is usually used to protect the Kevlar from UV. Therefore it is a hybrid rope consisting of a Kevlar core (typically yellow) and a Dacron jacket (usually black or olive green).
Preparing the Ends of Kevlar Rope
EXAMPLE: Spiderbeam 2mm Kevlar Rope
This 2mm Kevlar rope has a yellow-colored Kevlar inner core, and a thin black Dacron outer cover to protect the Kevlar from ultraviolet. The Dacron cover tends to fray easily on its ends, and should be properly prepared before use.
¨ Carefully pull the black Dacron cover back on itself about 2.5cm (1”), away from the end of the yellow Kevlar core, by holding the yellow tip with the fingers of one hand and pulling the black Dacron back with the other hand.
¨ While holding the Dacron cover in place, take a SHARP pocketknife and cut off about 2.5cm (1”) of yellow Kevlar protruding from the Dacron.
<<< CAUSTION – DO NOT CUT YOURSELF >>>
¨ While holding the rope with one hand about 10cm from its end, pull the end of the Dacron cover with the other hand, stretching it as far as you can. It will return to its original length.
Ø Please wear protective leather gloves for the next two steps:
¨ Using a cigarette lighter or a match, heat the end of the Dacron until it to catches fire. Allow to burn for about 1 second and blow out the fire. Do not let it burn to the point where the Kevlar core starts. Then QUICKLY perform the next step.
¨ Wearing gloves, round out the melted “bulb” of Dacron by slightly stretching it with your fingers. Instead of wearing gloves, you may also use a thin wet sponge.
<<< CAUTION: MELTED DACRON IS VERY HOT ! >>>
¨ Trim any long thin strings of Dacron that may be created with wire cutters or a knife.
Ø When completed, it should look like this: