Zippers are a commonplace part of our clothing and bags that we scarcely notice until they break. One of the most common zipper malfunctions is misalignment. When this happens, the zipper moves freely back and forth, but does not join the two sides together. This most often happens with closed-end zippers such as those found on purses and duffel bags.
To understand how to fix a misalignment, you need to know the parts of a zipper. The piece that you move back and forth with your hand is the slider. The teeth are the little metal or plastic pieces that lock together. The square piece at the end of the zipper is the stop bottom.
Things You'll Need
Completely unzip the zipper.
Examine the teeth of the zipper. When you zip up a zipper, the teeth on either side lock together. Sometimes, missing teeth can cause a misalignment in the zipper and prevent closure. It is difficult to replace zipper teeth and you may need to replace the entire zipper.
Check to see that the zipper is not misaligned. When you unzip the zipper all the way, you may notice that one side of the zipper bunches up a little between the slider and the stop bottom. If this is the case, the zipper is misaligned. Even if you zip the zipper up and it seems to stay closed, over time the teeth below the slider will work their way apart.
Spray or rub lubricant on the teeth. YKK, the world's largest zipper manufacturer, makes a lubricant specifically designed for zippers, but mineral oil works just as well.
Pull the misaligned side of the zipper through the slider until there is no bulge and both sides are even. The lubricating spray will allow you to do this without putting too much stress on the teeth and possibly breaking one of them. Return the slider all the way down to the bottom of the zipper so that it is flush against the bottom stop.
Hold the two rows of teeth that feed into the zipper close together. Trying to use a zipper with the rows of teeth stretched far apart is the cause of many zipper problems. A good example of this is when you try to zip up an overfilled bag and the opening is practically bulging apart. Holding the teeth close together reduces the risk of malfunction.
Slowly zip up the zipper. If you see the teeth join together starting right at the stop bottom, then you have fixed your zipper. If not, try Step 4 again.