Cap And Close Post

Definition and Overview

A cap and close post is a fastening item that is inserted through textile, leather, or similar materials and fixed by deforming the opposite side. It can reinforce areas where load tends to concentrate with sewing alone, and is also used as an accessory to add a metal-like design. After installation, it is a permanent fastening part that is generally difficult to remove.

Unlike press fasteners, it does not have an opening and closing function; it is mainly used for fastening and reinforcement. While an eyelet washer protects the area around a hole, a cap and close post differs in that it fastens multiple layers or parts together.

Materials and Structure

A typical cap and close post consists of a head visible on the front side and a leg or receiver part that passes through the textile. Because the combination is determined for each product, parts with different standards must not be mixed even if their appearance or diameter is similar.

Materials include metals such as brass, iron, and aluminum, and the surface may also be plated or painted. A type with heads visible on both sides may be called a double-sided cap and close post, while a structure with the receiver part or the processed leg visible on the back side may be called a one-sided cap and close post, though the terminology varies by trading partner.

• Head: the decorative part that appears on the front side, such as round or flat shapes.
• Leg: the part that passes through the textile and deforms during setting to secure the item.
• Receiver part: the part that receives the leg and fastens it; a washer may be used together depending on the structure.

How Sizes Are Shown and How to Install

In many cases, size is indicated by the diameter of the head. However, you cannot choose based on diameter alone, because leg length, compatible textile thickness, and the part combination also affect fastening strength. Specifications should allow confirmation of the front-side diameter, color/finish, part configuration, and compatible textile thickness.

Installation uses a setting tool that matches the part and a hand press or press machine. Methods include making a pilot hole in advance with a punching tool or similar, and piercing the textile with the leg. Before mass production, perform test setting on the same number of layers as the actual textile and confirm the finish on both sides.

• Use a dedicated setting tool to prevent deformation or damage caused by a tool that does not match the part.
• Adjust the setting pressure according to the part, textile thickness, and whether interfacing or reinforcement materials are used.
• After fastening, check for rotation, looseness, pull-out, surface damage, and crushing on the back side.

Main Applications

Cap and close posts are used in areas subject to pulling or repeated force, such as pocket openings, the bases of belt loops, tabs, handles, and straps. They are often seen as reinforcement around pockets in denim products. They are also used in bags, workwear, outerwear, and costumes that make use of decorative appeal.

In addition to fastening textile, they are also suitable for applications where tape, leather, synthetic leather, or metal hardware is layered and secured together. However, on soft thin fabrics or highly stretchy textiles, force tends to concentrate around the cap and close post, so reinforcement methods should be considered as well.

Points to Note When Selecting

If the leg is too short, it cannot be sufficiently set and is more likely to pull out. Conversely, if it is too long, excessive crushing on the back side or tilting of the part may occur. Textile thickness should be judged based not only on the outer fabric, but also on the actual stacked thickness including interfacing, facing, and tape. If necessary, add pressing cloth or reinforcement interfacing.

With metal products, rust, discoloration, and deterioration of the plating may occur due to sweat, moisture, washing, or storage conditions. Products that undergo washing or garment dyeing should also be checked for appearance and strength after processing. For applications that come into direct contact with the skin, confirm whether nickel-free is required and what plating specification will be used.

For products that require needle detection, manage in advance the sections using metal cap and close posts and their impact on the needle detection process. Even if a part is labeled as needle detector compatible, it is important to confirm in the actual process whether it meets the needle detection conditions and product specifications.

Frequently Asked Questions

What is the difference between a cap and close post and a press fastener?

A cap and close post is a part used to permanently fasten and reinforce textile or other parts, and it usually does not open or close. A press fastener is a part that opens and closes by attaching and removing the raised and recessed parts. Even if they look similar, their applications, part configurations, and setting tools differ, so check compatibility before selecting.

How do you choose the leg length of a cap and close post?

Choose based on the thickness of the overlapped area, including not only the outer fabric but also interfacing, tape, and pressing cloth. If the leg is too short, fastening will be insufficient; if it is too long, it may cause crushing or tilting. Match the part and setting tool you will use, and judge by performing test setting with the same material composition as mass production.

Can cap and close posts be attached to thin fabric?

Yes, but if they are set only into thin fabric, the hole may widen, the part may pull out, or the surrounding area may tear more easily. Consider adding pressing cloth or reinforcement interfacing on the back side to distribute the load. Because the result varies depending on fabric density and stretch, confirm strength and appearance through testing.