STUDIO D'ARTISAN "D4620" GL3 DENIM COVERALL
The Studio D’Artisan D4620 GL3 Denim Coverall is built around one of the most characterful fabrics in Japanese denim: heavyweight 15oz denim woven slowly on a vintage Toyoda Automatic Loom Works GL3 shuttle loom.
Originally developed around half a century ago, the GL3 represents an early generation of Japanese power looms. Today, keeping these machines running is an involved process. Replacement parts are no longer readily available, meaning worn components often have to be salvaged from other retired GL3 machines. Even by vintage shuttle-loom standards, production is remarkably slow, with the loom capable of weaving only around 5 meters of fabric per hour.
That inefficiency is precisely what makes the resulting denim so special.
Rather than producing the perfectly uniform surface associated with modern high-speed weaving, the GL3 creates a fabric full of irregularity, slub, texture and natural variation. The finished denim has the rugged, uneven character associated with workwear denim from generations ago — a depth and roughness that is extremely difficult to reproduce with modern machinery.
For the GL3 Series, Studio D’Artisan went further than simply putting denim through an old loom. The brand developed its own carefully calibrated recipe, experimenting with the texture and count of the yarns, the shade of the rope-dyed indigo, and the warp and weft density. Numerous test weavings were carried out before arriving at the final fabric.
The result is a 15oz GL3 selvedge denim with a distinctly vintage hand and pronounced surface character. The unevenness is intentional: every slub, irregularity and subtle variation contributes to the personality of the cloth. The denim is designed to develop further with wear, rewarding the owner with increasingly individual fading and character over time.
The D4620 itself takes the form of a classic denim coverall, drawing directly from traditional workwear while avoiding a boxy or overly utilitarian appearance. Its gently flared A-line silhouette gives the jacket a distinctive shape, combining the practicality of a traditional chore coat with a more refined contemporary profile.
Details reinforce its workwear roots, including large utility pockets, original Studio D’Artisan metal hardware, selvedge detailing and a leather neck patch. The jacket is constructed from 100% cotton and is available in a one-wash finish, making it easier to wear from the outset while retaining the substantial character of the GL3 cloth.
This is not simply a coverall made from heavyweight denim. It is a jacket built around a piece of textile history — a fabric that can only exist because an increasingly rare vintage loom is still being kept alive.
KEY DETAILS
- Model: Studio D’Artisan D4620
- Name: GL3 Denim Coverall
- Fabric: 15oz GL3 selvedge denim
- Composition: 100% cotton
- Loom: Vintage Toyoda Automatic Loom Works GL3 shuttle loom
- Weave: Traditional low-speed shuttle-loom construction
- Denim character: Highly irregular, slubby, rugged and textured
- Dye: Rope-dyed indigo warp
- Finish: One Wash
- Silhouette: Gentle A-line / slightly flared hem
- Hardware: Original Studio D’Artisan metal buttons
- Details: Selvedge detailing, utility chest and waist pockets, interior pocket, leather patch and locker-loop detailing
- Made in: Japan
WHY THE GL3 MATTERS
Modern denim production is built around speed, consistency and efficiency. The GL3 represents almost the opposite philosophy.
It is slow, demanding and increasingly difficult to maintain — but that lack of efficiency allows the loom to produce a fabric with an organic irregularity that modern machinery struggles to replicate. Studio D’Artisan has deliberately embraced those imperfections rather than attempting to eliminate them.
The D4620 GL3 Coverall is therefore a particularly pure expression of Japanese reproduction workwear philosophy: use historically authentic machinery, develop the fabric from the ground up, accept the limitations of the process, and allow those limitations to become the defining character of the finished garment.
At 15oz, it has the substance expected from serious workwear denim, while the A-line cut gives it enough shape and versatility to work equally well as a daily jacket.
A rare loom. An uncompromising fabric. A timeless workwear silhouette.
The D4620 is Studio D’Artisan’s GL3 denim translated into one of its most wearable forms — a coverall designed to age, fade and develop into something increasingly personal with every year of wear.
