Buttonhole Sewing Machine
A buttonhole sewing machine is a specialized sewing machine used to make buttonholes suitable for opening and closing by reinforcing the edges around the cut opening of a garment buttonhole with oversewing to prevent fraying.
Contents6 sections
Definition and Overview
A buttonhole sewing machine is a dedicated machine for sewing buttonholes, the openings used to fasten buttons. Before and after making an opening in the fabric, it covers the edges around the cut with dense oversewing to prevent fraying. It is used in mass production sewing to keep the stitch shape, buttonhole length, and oversewing density consistent.
A buttonhole refers to the opening itself used to fasten a button, while a buttonhole sewing machine refers to the machine that sews it. It is also different from a button-sewing machine, which sews buttons onto garments.
Hole Shapes and Corresponding Specifications
Typical shapes include a straight-end buttonhole with straight ends and an eyelet buttonhole with a round reinforced section at one end. Straight-end buttonholes may be used for shirts and blouses, while eyelet buttonholes may be used for thick jackets, coats, and front openings on pants.
Buttonhole length is determined not only by the button diameter, but also by the button thickness, shank height, and overlap of the garment. For shank buttons or thick buttons, more clearance is needed for passage than with flat two-hole or four-hole buttons.
- Straight-end buttonhole: a standard buttonhole with both ends finished round or straight.
- Eyelet buttonhole: a shape with a round eyelet-like opening at one end to reinforce areas subject to stress.
- Eyelet button: a type of button that uses metal parts, and a different term from eyelet buttonhole.
Specification Instructions and Size Management
In a buttonhole specification sheet, clearly state the hole shape, finished buttonhole length, oversewing thread color, oversewing density, cutting direction, and relationship to button placement. During prototyping, it is important to combine the actual outer fabric, interlining, and button to check opening and closing.
Button size may be shown in lignes or millimeters, but buttonhole length is generally specified in millimeters. Even when using buttons marked in lignes, listing the button diameter in millimeters in the specification sheet makes it easier to avoid misunderstandings with the factory.
Main Applications and Sewing Precautions
Buttonhole sewing machines are used for garments with button openings, such as shirts, blouses, jackets, suits, coats, pants, and skirts. The suitable hole shape, interlining, thread, and sewing conditions vary depending on fabric thickness, stretch, and the degree of fuzziness.
On thin fabrics or stretchy knits, fusible interlining or stay tape may be used to prevent the area around the buttonhole from stretching or wavering. On thick fabrics, buttons can become difficult to pass through, so confirm not only the hole size but also how well it opens after cutting.
Handling and Quality Inspection
The effects of washing, dry cleaning, and ironing differ depending on the combination of buttonhole thread, outer fabric, and interlining. After washing, check for fraying around the buttonhole, thread breakage, deformation caused by shrinkage, and interlining peeling. For the buttons themselves, also check for cracking, chipping, discoloration, and damage to the finish, depending on the material.
If ironing presses the buttonhole area too firmly, it may affect the three-dimensional appearance of the oversewing thread and the opening of the buttonhole. Based on the product care label and the handling conditions of the buttons and sewing thread used, perform washing tests and appearance checks before mass production.
Frequently Asked Questions
What is the difference between a buttonhole sewing machine and a button-sewing machine?
A buttonhole sewing machine is a machine that makes buttonholes for buttons using oversewing. A button-sewing machine, on the other hand, is a machine that sews two-hole or four-hole buttons onto fabric. For products with a front opening, both processes are usually required.
How do you determine the length of a buttonhole?
While using the button diameter as a reference, determine it by checking the thickness, shank height, thickness of the outer fabric and interlining, and ease of button passage. It is important not to decide based on numbers alone, but to make a prototype with the same accessories as mass production and check the ease of opening and closing as well as the appearance around the buttonhole.
When are eyelet buttonholes used?
An eyelet buttonhole is a shape with one end of the buttonhole roundly reinforced. It is generally used in areas such as front openings that are likely to be pulled, and in thick garments. However, suitability depends on the design, fabric thickness, button shape, and sewing equipment.
