A suitcase zip always sticks at the worst moment: when everything is packed and the taxi is pulling up. It is a common problem, because a zip is made of small moving parts whose gaps collect dust, sand and crumbs. Over time the dirt builds up on the teeth and slider, and the zip starts to jerk.
The good news is that in most cases the zip does not need replacing. Cleaning and lubricating it properly is usually enough.
What you will need
Important: Cover the fabric or leather next to the zip with paper before applying. On light-coloured fabric and leather, test the product on a hidden spot first.
Step 1
Check the zip's condition
Before applying anything, make sure the zip is not physically damaged: look for bent or missing teeth or a cracked slider. Most often, though, the problem is dirt. Brush out crumbs, dust and sand with a soft brush or blow the mechanism clean. A household vacuum with a crevice tool also works.
Step 2
Lubricate the mechanism
Protect the surrounding surfaces with paper and use the straw to apply a small amount of WD-40 Specialist Silicone to the slider and teeth. Silicone lubricant is safe on plastic teeth, leaves no greasy marks and does not attract dust.
For metal zips and fittings, WD-40 Multi-Use also works: it penetrates stuck parts, displaces moisture and protects metal from corrosion. The straw lets you aim the spray exactly where it is needed.
Step 3
Wipe off the excess
After applying, wipe the zip with a dry cloth. This keeps it clean so it does not pick up new dirt on the road, and keeps lubricant off the clothes inside.
Step 4
Test the zip
Open and close the zip along its full length several times so the lubricant spreads evenly inside the slider. If it still feels stiff, reapply at the problem spot. While you are at it, lubricate the wheels and telescopic handle if they squeak.
Step 5
What to do without a can to hand
On a trip, a few temporary tricks can help. Rub the teeth with an ordinary pencil, as graphite reduces friction. You can also rub them with plain white candle wax or a dry bar of soap, then run the slider up and down a few times. These fixes do not last long, so clean and lubricate the zip properly once you are home.
Tip: Never drag the suitcase by its zip pull or force it shut over bulging contents: an overloaded zip is the one most likely to split. Repack a few items or use a luggage strap instead.
What next
Lubricate your suitcase zips before each travel season. For wheels, locks and metal fittings, WD-40 Smart Straw is handy to keep alongside your travel care kit.
These uses come from the experience of WD-40 users in many countries. Always follow the instructions and warnings on the product label.
More guides in «How to use».