Bar Tack
A bartack is a sewing specification that reinforces areas where stress is concentrated, such as pocket openings and the ends of belt loops, with short back-and-forth stitching to prevent fraying and tearing.
Contents6 sections
Definition and Overview
Bartacking is a reinforcing stitch that is sewn at high density in a zigzag or back-and-forth pattern within a fixed width and length range to withstand localized stress. Because the stitches appear bar-shaped, it is called bartack in English.
It is mainly done with a dedicated bartack machine, but depending on product specifications and equipment, substitute sewing with another machine may also be considered. It is a specification that affects not only appearance but also the strength of the sewn area.
- Both ends of pocket openings
- Top and bottom ends of belt loops
- Ends of zipper openings
- Ends of slits and plackets
- Attachment points such as bag handles
Process in Product Manufacturing
Bartacking is generally performed in the sewing process after cutting, after the parts have been sewn together and attached components such as pockets and loops have been installed. If it is added too early in the process, the bartack section may overlap with later sewing steps or workability may decline.
Before mass production, the position, direction, and stitch shape are checked on samples, and the approved specification is reflected in the mass-production instructions. For products that are washed or garment-dyed, shrinkage after processing, thread breakage, and puckering are also checked.
Specification Decisions and Procedure
The specification sheet should clearly indicate the locations where bartacks are to be added, the front and back sides, the sewing direction, and the finished position. For paired areas such as pocket openings, dimensions and directions from a reference point are specified to prevent left-right differences or height differences.
The stitch length, width, number of passes, thread color, and thread type are determined according to the thickness and structure of the textile, the application, and the desired appearance. Thin bartacks are less noticeable, but depending on the load and the characteristics of the textile, they may not provide sufficient reinforcement.
If the textile is thin or highly elastic, overly dense stitching can easily cause shrinkage or waviness. If necessary, consider the interlining, pressing cloth, and sewing conditions together.
Ordering and Quality Precautions
When placing an order with a sewing factory, do not rely only on symbols in the specification sheet; indicate the bartack locations in a diagram and, if possible, share a sample or approved sample. If you only instruct them to "reinforce it," the interpretation of the position, shape, or sewing direction may differ.
During inspection, check for misalignment from the specified position, uneven left and right sides, skipped stitches, thread breakage, skipped stitches, and overlapping stitches. Also check whether there is any tearing of the textile, needle holes, puckering, or significant puckering around the bartack.
For products where strength is important, it is effective to perform a tensile test assuming actual use. However, the required strength and test method differ depending on the product application and customer standards, so they must be agreed in advance.
Differences from Similar Terms
Single needle stitching refers to the basic sewing method that uses an upper thread and a lower thread, whereas bartacking refers to a sewing specification for reinforcing specific stress-bearing areas. Bartacking differs from single needle stitching in purpose and scope of application.
Overlock is a sewing method that joins fabric while preventing fraying at the edge. In contrast, bartacking is not for finishing a fabric edge; it is used to prevent the ends of areas such as pocket openings from tearing or the stitching from fraying.
Frequently Asked Questions
Where is bartacking needed?
It is used in areas where pulling or repeated stress is concentrated. Typical examples are pocket openings, belt loops, zipper ends, and slit stops. However, necessity should be determined based on the product application, textile strength, and sewing specification, while also checking the balance with appearance.
Should the bartack thread color match the textile?
In many cases, a thread color that blends with the textile or surrounding stitches is chosen. On the other hand, workwear and denim products may use bartacks as a design feature with contrast thread. While maintaining the reinforcing function, it is important to check how visible the stitches are and the overall consistency between left and right sides.
What should be done if the textile tears at the bartack?
Possible causes include stitches that are too dense, needles or thread that are unsuitable for the textile, or concentrated stress. In addition to adjusting the sewing conditions, consider changing the bartack dimensions, reinforcing with a pressing cloth or interlining, and reviewing the attachment position and part design.
