Repairing zips and buckles on the move

Inside the slider there is a channel shaped like a Y. At the top the two rows of teeth come in separately; at the bottom they come out joined. When closing, the channel guides the rows towards each other at an angle and presses them together so that each tooth engages in the gap opposite. When opening, the central divider inside the slider separates the rows again.

The slider is made of two plates, top and bottom, joined by this divider. Through frequent use, strain on the fabric or sand in the zip, the plates bend apart very slightly over time. Even a tiny extra gap is enough for the teeth no longer to be pressed together firmly. Gently squeezing the plates restores the original gap.

A side-release buckle does something much simpler: it joins two strap ends so they can be opened quickly. A knot in the webbing or a cord loop takes over the same tension connection – it is just more awkward to open and adjust.

Before you reach for the pliers, look closely. If the zip jams, fabric or a thread has often been pulled into the slider. Pull it out carefully instead of forcing the slider onward – otherwise the fabric tears or the slider gets distorted.

If the zip runs stiffly, there is often sand, dirt or salt between the teeth. Rinse it with water and brush it clean with an old toothbrush. That alone solves some problems.

Only if the zip is clean and still opens behind the slider is the slider usually worn. If, on the other hand, teeth have broken off or the tape the teeth sit on has torn out, squeezing will not help – then you need a stopgap and later a proper repair.

Run the slider all the way down to the start of the zip. Put the pliers on the rear, open end of the slider – where the separated rows of teeth come out – and squeeze the two plates together very slightly, evenly on both sides. Then test. If the zip still does not hold, repeat the step with just a little more pressure.

Small steps are what matters most. With too much force the slider breaks, especially if it is plastic or thin metal, or it jams so tightly afterwards that it will not move. A squeezed, worn slider will not last forever either; but it often buys you time until a proper repair.

If the pull tab is missing, thread a piece of cord, a key ring or a paper clip through the eye on the slider. If nothing helps, you can close a zip from the inside with safety pins or sew it shut with large stitches. On a jacket this at least keeps you warm until it can be repaired.

If a side-release buckle on a hip or sternum strap breaks, join the two straps with a water knot, also called a tape knot. It is the usual knot for joining flat webbing. Pull it tight firmly and leave the tails good and long, because webbing can slip in knots over time.

Alternatively, fix a cord loop to one strap end, thread the other end through and tie it off. Remove broken buckle remnants so they do not chafe or dig into you.

For the future, a spare buckle in the repair kit is worthwhile. There are clip-on replacement buckles for common strap widths that can be fitted without sewing. Measure the width of your straps beforehand.

For anything that protects people there is one clear rule: buckles and fastenings on climbing harnesses, helmets, child seats, life jackets, avalanche equipment and other protective gear are never repaired by improvisation. Such parts must withstand tested forces. If something is broken there, the equipment is retired and replaced.

When working with pliers, the slider can slip or break. Work calmly, keep your fingers out of the way in case the pliers slip, and do not squeeze in a jerk.

A permanent zip repair means a new slider or a whole new zip, for example at a tailor's or through the manufacturer. For sleeping bags, tents and expensive jackets it is almost always worth it.