In the Details: Knurled Welding, and How It Makes for Some Seriously Tough Bike Bags
Posted in: In the DetailsLike a lot of successful entrepreneurial ventures, Chrome Industries was born of out dissatisfaction. Its founders were a group of Boulder, Colorado, cyclists who couldn’t find a messenger bag that met their standards—so they started making their own, using military-grade materials and salvaged seatbelt buckles. Now based in San Francisco, Chrome has been selling those messenger bags for almost 20 years, alongside a growing collection of similarly tough backpacks, apparel and other gear.
The latest addition to that collection is a line of what Chrome calls “knurled welded waterproof rolltops,” released two weeks ago. The four bike bags (two backpacks, a front-rack duffle, and a saddle bag) sport roll-top closures and distinctive exterior seams with a nubby texture—evidence of that “knurled welded” technique, which the company says creates superior durability with very little weight.
So how does knurled welding work? Knurling usually refers to a surface treatment used on wrenches and other metal tools; in those cases, it creates a raised pattern that provides better grip. In knurled welding, that raised pattern is printed on both sides of the tool used to RF-weld pieces of fabric together. (Envision two waffle irons coming together.) This creates more surface area along the seams, which equals greater strength.