Triple Fold
Triple fold is a sewing specification that finishes hems and edges by folding the fabric edge inward twice to enclose the raw edge and stitching near the fold line.
Contents6 sections
Definition and Overview
Triple fold is a method of finishing edges by folding the cut edge of the fabric once, then folding it inward again and stitching it. The raw edge becomes less visible from both the front and back, creating a relatively neat hem or perimeter while reducing fraying.
It is used for shirt and blouse hems, skirt hems, and the edges of handkerchiefs. Because it refers to the structure in which the fabric becomes three layers when finished, rather than the number of folds made, the fold width and stitch position vary depending on the product specification.
Position in the Process
In general, after cutting, any necessary interfacing is applied and the main seams are sewn, then the hem opening and similar areas are triple folded and stitched. Whether seam allowances at side seams or the center front and back are pressed to one side affects the thickness and appearance of the triple-fold area.
In mass production, besides the method of pressing in the folds with an iron before stitching, there is also a method in which a fold guide called a folder is attached to the sewing machine so folding and stitching can be done continuously. Process settings are adjusted to the fabric thickness, stretch, and degree of curve.
Procedure and Practical Points
Specifications should clearly state the finished fold width, stitch position, whether topstitching is visible on the front side, and the stitch type to be used. It is important to distinguish between pattern dimensions including seam allowance and finished dimensions, and to set them so the product length will not be insufficient after folding.
While straight sections are stable and easy to sew, strong curves and corners are prone to puckering and distortion because of the difference between the inside and outside. Adjust the fold width according to the curve, and if necessary make clips or ease in fullness, then check the appearance with a sample.
- On lightweight fabrics, check for sewing shift or waviness.
- On heavy or firm fabrics, check the thickness at the folded layers and needle penetration.
- On patterned fabrics, check that the pattern does not tilt or break at the hemline.
- On stretchy knits, feed without pulling to prevent stretching during sewing.
Ordering and Quality Considerations
When placing an order with a sewing factory, share not only the name triple fold but also the fold width, number of stitches, sewing thread color, stitch width, and finishing position with samples and specifications. Because foldability and sewing conditions change when the fabric changes, confirm a production approval sample using the actual fabric before mass production.
During inspection, check variation in fold width, raw edge protruding beyond the stitches, puckering, skipped stitches, and distortion at curved sections. For fabrics that shrink or twist after washing, also evaluate waviness at the hem and deformation of the stitches.
Differences from Similar Terms
Edge finishing refers to any method used to prevent the raw edge from fraying, and triple fold is one specific method. Overlock is a method of finishing the cut edge with an overcasting stitch, and its structure and appearance differ from triple fold, which folds the fabric edge inward twice.
Triple turn is sometimes used with the same meaning as triple fold, but it may especially refer to finishing that rolls in the edge with a narrow fold width, or to stitching using a dedicated folder. When ordering, do not rely on the name alone; confirm with a finished sample and dimensions.
Frequently Asked Questions
How do you determine the seam allowance for a triple fold?
Based on the finished fold width, set in the pattern enough seam allowance to fold twice. The required dimensions vary depending on fabric thickness, curve, and whether a folder is used. Since insufficient seam allowance can lead to the raw edge protruding, confirm with a sample made under the same conditions as mass production.
How do you choose between triple fold and overlock?
Triple fold is suitable for hems and edges where you want to hide the raw edge and achieve a neat appearance on both the front and back. Overlock is a finishing method that overcasts the edge to prevent fraying, and it is also used for seam finishing and areas that require stretch. Select it based on the application, appearance, and fabric thickness.
What causes hems to wave with triple fold?
Causes include sewing while pulling the fabric, excessive sewing thread tension, and uneven folding. This is especially likely with stretchy fabrics and on bias sections, so adjust the feed conditions, presser foot, stitch settings, and ironing process using a sample.
