Best Elastic for Sewing Swimwear

When it comes to sewing swimwear, clear elastic, rubber elastic and cotton wrapped rubber serve similar purposes—providing stretch and support—but they differ significantly in durability, feel and ideal application. Here's a comparison of their functions in swimwear construction:

1. Stretch and Elasticity

 

*Note: for specific stretch on styles we carry, please refer to each style on the website.

Clear Elastic:

• Made from thermoplastic polyurethane (TPU), clear elastic provides strong stretch but retains its shape and elasticity over time.
• It offers excellent recovery (returns to its original length after stretching) and maintains stretch even after exposure to water but is less resistant to chlorine, UV, and long-term tension compared to swim elastics. Also, it is not as durable as other options, see Longevity section.
• Its stretchability is consistent, offering smooth and controlled stretch, which is crucial for swimwear.
• Often comes in different thicknesses and widths which may affect the stretchability.

 Rubber Elastic:

• Rubber elastic (often made from natural or synthetic rubber) also provides a high level of stretch and has excellent elasticity.
• It can stretch very easily, which gives it a high "snap-back" effect. However, some rubber has a tendency to lose some elasticity over time when exposed to chlorine or saltwater.
• It can feel a bit more "snug" and firm compared to clear elastic, which may offer a different fit in swimwear.

Cotton Wrapped Rubber Elastic (Chlorine Resistant Swim Elastic):

• Excellent stretch and recovery, it returns to original shape after stretching

2. Durability and Longevity

Clear Elastic:

• Clear elastic is chemically resistant. Works well when used in protected inside seams and when not under heavy tension. It is not as sun or chlorine resistant as rubber options, and we prefer it in lingerie and athletic wear as opposed to swim, where conditions are harsher.

Rubber Elastic:

• While rubber elastic provides a good amount of stretch, it can degrade over time when exposed to chlorine and saltwater, which can cause it to lose its elasticity more quickly. Not all rubber is created equal. Swimwear grade rubber elastics are specifically designed to resist this and perform well over time.
• Over time, rubber elastic can become brittle or lose its stretch due to exposure to harsh elements. However, this can be said of almost any elastic. Heavy sun exposure and heat can degrade elastics faster than any other factor.

Cotton-Wrapped Rubber Elastic (Chlorine Resistant Swim Elastic):

• Offers good longevity in swimwear when specifically manufactured as chlorine-resistant swim elastic. The rubber core provides strong stretch and recovery while the outer cotton improves comfort and protects the elastic during wear. Cotton itself is not inherently chlorine-resistant unless treated, not all cotton elastics are suitable for swimming conditions.

3. Appearance

Clear Elastic:

• Clear elastic is nearly invisible when used in swimwear, making it perfect for use in areas such as along seams or in areas where minimal visibility is desired. It is less commonly used for structural areas like leg openings.
• It is especially useful for sheer or lightweight fabrics used in dance and skating costumes, as it won’t detract from the garment’s appearance.

Rubber Elastic:

• Rubber elastic, although functional, is generally more visible than clear elastic, especially in light or sheer swimwear fabrics.

Cotton-wrapped Rubber Elastic (Chlorine Resistant Swim Elastic):

• The style we use most is ½” in a natural color. It is more visible but wider elastic can also be comfortable
• It can be less discreet, which may not be as aesthetically pleasing if you are trying to maintain a clean, smooth appearance.

4. Comfort and Fit

Clear Elastic:

• Clear elastic provides a softer, more comfortable fit because it is made from flexible TPU. It doesn't dig into the skin, and its smooth texture helps avoid irritation. However, this depends on the thickness of the style. Varies significantly from supplier to supplier.

Rubber Elastic:

• Rubber elastic can feel firmer and potentially tighter, offering a stronger hold. However, this can sometimes lead to discomfort or pressure on the skin, especially if the elastic is not used properly or if the garment is too tight.
• In swimwear, it may provide a more supportive, compressive fit, but the tighter feel could be less comfortable for extended wear.

Cotton-wrapped Rubber (Chlorine Resistant Swim Elastic):

• Cotton wrapped elastic is often perceived as more comfortable because the cotton layer sits against the skin. However, cotton wrapped rubber is often constructed as a braided elastic, with lengthwise narrow ribs. It is generally considered comfortable in most applications, and our experience agrees with this.

5. Use in Specific Swimwear Areas

Clear Elastic:

• Seam Reinforcement : Clear elastic is good for reinforcing seams in swimwear to prevent stretching and maintain shape, especially in high-stress areas like crotch seams or side seams. Consider clear elastic to be light-duty or for stabilization.

Rubber Elastic:

• Leg Openings : Rubber elastic is often used in areas where a stronger hold is needed, such as tight leg openings that need a more substantial grip to stay in place.
• More Compression: It's more commonly found in more compressive designs of swimwear, such as high-performance or competition suits, where a firm fit and additional support are crucial.

Cotton-wrapped Rubber (Chlorine resistant swim):

• Used in similar applications to rubber elastic.

6. Ease of Use

Clear Elastic:

• Clear elastic is relatively easy to sew into swimwear fabrics because it can be handled gently and doesn’t require special techniques. It can be stitched directly into seams or inserted into casings with ease.

Rubber Elastic:

• Rubber elastic can be more difficult to work with because of its high stretchability. You may need to stretch it as you sew it in place to avoid puckering or uneven stitching. It also needs careful handling because excessive stretching can lead to damage or loss of elasticity.

Cotton-wrapped Rubber (Chlorine Resistant Swim Elastic)

• Easy to use.
• While you must be careful not to cut into any elastic while serging it to the garment, wider widths allow for the occasional error with no real damage to the elastic. Narrower widths can be less forgiving. Cotton wrapping may reduce reaction to those who are mildly sensitive to latex.