Invisible Zippers

It is hard to imagine a world without zippers but they are a fairly recent invention. Whitcomb Judson came up with the idea of a slide fastener that could be opened and closed with one hand. He patented the “clasp locker” on August 29, 1893. Their use was limited because they weren’t considered practical.

Judson’s employee, Gideon Sundback, improved on the idea and patented the “hookless fastener” in 1913. The US Army was one of Sundback’s first customers. They used them on clothing and gear in World War I. Zippers didn’t come into popular use until B.F. Goodrich decided to use them in galoshes. An executive is said to have named the device a ‘zipper’ because of the sound it made.

Todays zippers work on basically the same design. The biggest change has been in the materials that make the interlocking teeth. Modern zippers of metal, nylon and molded plastic are much thinner and easier to work than the original model. Metal zippers are used primarily for jeans, heavy jackets, men’s trousers and camping equipment. They are strong but if one tooth is lost the entire zipper must be replaced. Molded plastic zippers are taking the place of metal zippers in many places, particularly in outerwear. They are strong and come in a wide variety of colors but if a tooth is lost the zipper fails. 

The most common zipper in use today is the coil zipper. They are designed for garments and other less bulky applications. Todays zippers are thinner, more flexible and self healing. Invisible zippers are a type of coil zipper.

Invisible zippers are used in many of the finest garments. Look closely at the garments in the Vogue pattern book and you will see they always use invisible zippers. The finest couture houses of Paris, London and New York use invisible zippers in their creations. An invisible zipper in the back of a square dance blouse or bodice will look smoother and neater than the traditional lapped zipper. They can also be used in skirts for the closure or to make a sealed pocket.

Invisible zippers have been around for years, but some experienced needle workers are afraid of them because they require a different application and a special presser foot. They are actually faster and easier to put in a garment than other type of zippers once the technique is learned. The invisible zippers today are thinner and more invisible than they were when first introduced. The very thinest are the Coats & Clark brand. If your machine does not have a specific invisible zipper foot you will need to get a universal invisible zipper foot. 

Invisible zippers do not come in as many colors as regular zippers. They don’t have to be an exact match because they don’t show. Just choose one that is closest to the color of the fabric. The instructions inside the Coats & Clark package are very clear. Please take the time to read them over very carefully.

To improve the appearance of any zipper, first stabilize the seam. Cut two strips of very light fusible interfacing about two inches longer than the zipper tape and one inch wide. Pellon 906 is a good weight. It is best if these are cut with pinking shears or a wavy edge rotary blade. Iron the interfacing to the wrong side of the garment along the seam line where the zipper will be applied. This will give the fabric more body to support the stress of the zipper and prevent the zipper from showing through on the right side. The reason for the pinked edge is to prevent it from making a line impression on the right side. This is one of those little steps on the inside of the garment that will greatly improve the finished appearance.

Pressing the zipper is the place where most people have trouble. The are afraid to really press the zipper with a hot iron because they think the plastic coil will melt. Zippers are made of a type of thermoplastic that can stand the heat of the dryer and the iron. Set the iron on 'synthetic' and use a good spray of water. Press firmly with the tip of the iron.P1020476 P1020472

 The coil needs to be pressed open and uncurled very flat so that the stitches can be made close to the teeth. The left side of the tape has been pressed. Do not close the zipper after pressing.


One change in the Coats & Clark© instructions is using Wash-away Wonder Tape® by Collins. It must be this brand. This 1/4 inch wide double sided tape can be sewn through then it washes away. Apply Wonder Tape to the front side of both halves of the zipper. Rub it down so it sticks firmly to the zipper tape. Leave the paper on until ready to sew.

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Peel off one side of the tape and stick the zipper to the right side of the fabric. The stitching line is right at the base of the teeth and should be 5/8 inch from the edge of the fabric. Most tape measures are 5/8 inch wide.

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This is a picture of the PFAFF brand invisible zipper foot. Some machines have brand specific invisible zipper feet or you can use generic invisible zipper feet that are sold at the fabric store near the zippers. All of them work the same way with two tunnels that fit over the teeth of the zipper. The newer feet will not work with the older zippers because the teeth on the older ones are too thick and the older feet will not do a good job on the new zippers because the tunnels are too big to guide along the zipper teeth properly.

Position the zipper foot so the tunnel is directly over the edge of the zipper tape. Increase the stitch length to 3.5 mm or 10 spi. This longer stitch length will reduce puckering. Sew until the zipper foot touches the zipper pull. Then back stitch about 5 stitches, cut the threads and pull them to the back.

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The stitching should be right in the groove at the base of the zipper teeth. Place the other half of the project right sides together with the zippered section. Peel the paper off the Wonder Tape and stick the zipper in place. 

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Sew the other side of the zipper. The stitching will be near the middle of the interfacing on the wrong side.

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To finish the seam, close the zipper and fold the project right sides together. Pul the tail end of the zipper out of the way. Change to a regular zipper foot. This picture shows a PFAFF brand foot but the idea for all zipper feet is the same. With the presser foot up, bring the needle down into the last stitch at the bottom of the zipper. By bringing the needle down first it holds the fabric in place. Then bring the presser foot down. 

Shorten the stitch length to 1 mm or 20 spi. Back stitch one stitch and sew about 1/2 inch. Increase the stitch length to 3.5 mm or 10 spi and  sew about two inches. Switch to the regular presser foot and finish the seam. Do not sew the entire seam with the zipper foot because it does not hold the fabric properly for regular sewing and tends to pucker.

For a final finishing touch sew down each side of the zipper tape along the very edge. Stitch the zipper tape to the seam allowance. This last step will make the zipper and seam allowance lay flatter. Sew the entire length of the tape to secure the bottom of the zipper and prevent it form curling.

This is a light green zipper sewn into blue fabric with red thread and all that can be seen is the zipper pull.

                                P1020526           Don’t be afraid to try new techniques and products in your sewing. Someone is always coming up with a change that makes sewing easier/faster/better. P1020527