The Welded Age: Advantages of Welded Seams

Bill Hartlieb, product designer, tester, and mastermind behind Stoic, gives us a quick lowdown on one of the brand’s signature technologies: welded seams.

Welded or bonded construction is not easy to do. If were easy, every company out there would do it. However, at Stoic, we’ve found the advantages of welding seams far outweigh the challenges of manufacturing.

Superior Waterproofing

First of all, welded jackets and pants have outstanding waterproof qualities. By welding materials together, you create a more waterproof seam than traditional sewing, which is done by top-stitching and then taping the seams. A welded seam contains no wicking materials in the seam, unlike sewn seams, which have 1000s of tiny holes and wicking threads that can absorb rain or melting snow.

Welded garments’ flat shear seams act like a roof: with the seams overlapping so rain and moisture drip over the seam and shed off the jacket, rather than soaking into the seam.

After much testing of true garments in the market, it has been found that seam tape can only support 3 psi of water pressure, while welding can withstand up to the material waterproofness, more like 14 psi of water pressure. For more information on waterproof ratings and seam taping, see the article Waterproof Ratings Demystified

Superior Comfort

A bonded seam is flat, with minimal extra layers added in. This creates a smooth, comfortable surface on the inside of the garment. This is in contrast to traditional sewing and seam-taping, where the manufacturer overlaps at least three layers of materials, sews them together with thread, and then backs it all with seam tape.

Also: welded seams are malleable and can stretch. Traditional sewn seam, with seam tape over the top ? Not so much. There is little to no stretch in this construction.

Simplicity

This isn’t rocket science: any welded jacket, pant or welded glove is made without stitching. Nada. No seam taping. Welded outerwear looks and feels lighter. Simple with less bulk.

Strength

Traditional stitches create stress points at each stitch. This is often where a seam begins to tear or fray apart. Welded seams distribute the load across the garment, minimizing stress and risk of blowout. This allows us to use thinner fabrics without comprising durability. Remember the stretch: a welded seam also stretches when put under stress. The sewn seam? Pop.

Design

Since we don’t have to factor in seams, we enjoy more flexibility when it comes to designing welded pieces. For example, on a jacket we can add pockets where we want, without the need of adding seams or paneling.

So Why Doesn’t Everyone Weld?

Welding is not easy to do reliably. While sewing is complex and requires many complex machines, a sewn seam can be quickly visually inspected and reviewed for quality and integrity.

For welding, the quality process is more involved. It demands professional selection and utmost consistency in materials and finishes.

At Stoic, we rigorously hand-select materials and test them for what we term “weldability.” We take pre-production samples of the materials and verify weldability through our proprietary testing techniques. After it is deemed weldable, we create the garment with the fabric. We then ensure the integrity of finished garments by putting them through over 24 hours of continuing testing, which correlates to roughly 7 years of use in the real world. If the outerwear doesn’t meet our requirements for strength, stretch, and waterproofing, we re-engineer and start all over until we get it right.

But welded seams are just the beginning. Be sure to check out our entire line of Stoic gear.