Bottom Stop

Definition and Overview

A bottom stop is a stopping part attached to the lower end of a zipper. When the slider is lowered, it catches that movement and prevents the slider from coming off the left and right tapes. It is a counterpart to the top stop, which prevents the slider from coming off at the upper end.

In general, a zipper with a bottom stop is a closed zipper whose lower end does not separate. The bottom stop itself is not a tooth, but it is an important part that fixes the end of the row of teeth and establishes the opening and closing range as a zipper.

Structure and Relation to Zipper Specifications

A zipper is mainly composed of teeth that engage to form the opening and closing section, a slider that engages and separates the teeth, zipper tape that supports the left and right sides, and top and bottom stops. The shape and attachment method of the bottom stop vary depending on the type of teeth, such as coil, resin, or metal.

In a closed zipper with a bottom stop, the slider does not move past the bottom stop. On the other hand, an open zipper is a specification in which the lower end can separate, and a separator is used instead of a bottom stop. A separator consists of a box and pin, and its function differs from that of a bottom stop.

• The larger the tooth size of the zipper, the more thickness and stiffness tend to appear around the bottom stop as well.
• When processing a chain zipper for a product, a bottom stop is attached at the specified position to make it a closed specification.
• Even with a two way separator zipper, a bottom stop may be used when the lower end does not open.

Main Applications

Closed zippers with a bottom stop are used in places that do not need the lower end to open, such as the front or side opening of pants and skirts, the back opening of dresses, pockets, and pouches. Depending on the application, choose the type of teeth, tooth size, slider shape, and tape color.

In apparel, concealed zippers are chosen for thin fabrics or openings that should not be visible, while coil, resin, or metal zippers are chosen for areas that require strength or design appeal. However, if any of these are closed specifications that do not separate at the lower end, the bottom stop becomes the endpoint of opening and closing.

How to Choose and Sewing Precautions

When selecting, confirm the intended opening use and required opening length, as well as the fabric thickness and stiffness, whether washing or garment washing will be done, and the tooth size. Since thickness tends to concentrate around the bottom stop, it is important to check in a prototype whether it shows through thin fabrics or creates sewing difficulty due to steps in thick fabrics.

Zipper length is often indicated based on the openable section from the top stop to the bottom stop. However, the notation method and overall length including the tape ends vary depending on the specification, so when ordering, confirm the required opening dimension and the measurement standard in the product specification sheet.

In sewing, avoid sewing directly through the bottom stop with the needle, and be careful not to let the stitching come too close to the row of teeth near the bottom stop. For products that will be washed or garment washed, evaluate in advance the waviness caused by fabric shrinkage, the load around the bottom stop, and slider operation.

Differences from Similar Terms

The top stop is a part that prevents the slider from coming off at the upper end of the zipper, and its attachment position differs from the bottom stop, which is attached to the lower end. The teeth are continuous parts that interlock on the left and right, and the slider is the movable part that opens and closes the teeth; both have roles different from the bottom stop.

A separator is a part that makes the lower end of an open zipper detachable. A bottom stop is a part that fixes the lower end and stops the slider from moving, so for uses such as front openings on blousons that need to separate all the way to the hem, a separator is usually used instead of a bottom stop.

Frequently Asked Questions

Can a zipper with a bottom stop open all the way to the hem?

A closed zipper with a bottom stop cannot separate left and right at the lower end because the slider stops at the bottom stop. For a front opening that opens completely from the hem, choose an open zipper with a separator instead of a bottom stop.

Where is zipper length measured from, including the bottom stop?

In general, the length of the openable section from the top stop to the bottom stop is treated as the zipper length. However, the overall length including the tape ends and the measurement position vary depending on the specification, so please confirm the same measurement standard in planning, ordering, and sewing.

Is it a problem to sew near the bottom stop?

If the needle hits the bottom stop, it can cause needle breakage or sewing defects. Set the stitching line in a position that avoids the bottom stop and the row of teeth, and for thick materials or materials with large steps, it is important to verify by test sewing, including the presser foot and sewing sequence.