After some mileage indoors or sport climbing, your rope may become fluffy, frayed and worn. Generally about a meter infront of the tying in section of rope. Look for signs on the outer sheath, and also test the core (bobbins strands) by feeling and bending the rope… it’s very unlikely any of these will have snapped, but they do become stretched/worn/twisted inside the sheath (mantle).
This kind of wear is very unlikely to happen on a trad climbing rope, because its caused by the repetitve resting or falling on to the quickdraws. Though it is very possible to get a nick or cut in a trad rope, and the same process of cutting or chopping the rope may be necessary.
I start by feeling the rope and getting the section where it becomes ‘good’ again. It’s not fluffy, bendy, and holds a nice loop as you pinch it together. This is the safe part you’re looking for.
I then tape with good quality duct tape as tightly as possible around the section I am going to cut.
Heat up a sharp knife with either a few candles or lighters, or on a gas hob… take care not to burn yourself and do it either outside or near a few open windows, as this is smelly and gives off fumes.
Cut straight through the duct tape. Then use a lighter to melt the duct tape into the shealth and into the core, so that it all welds together and won’t fray. I then roll the still hot edges on some newspaper to round them off a bit and avoid any sharpness.
Be sure to clean all the black gunk off the knife before you put it back in the draw and your non-climber wife/girlfriend/mum finds it.
After chopping the rope 3 or 4 times, take a moment to consider the state or the middle section, the rope is probably quite tired, and could do with being retired. For £150 the price per usage is negliable… check out V12 Outdoor shop in Llanberis for some great deal, and you get 15% off, if you are or have been on one of my Rock Climbing courses.