Challenge’s Ultraweave fabrics have seen impressively broad acceptance this winter, with companies as diverse as Pa’lante and Stone Glacier using it, and companies like MLD and Seek Outside moving to make it a core part of their pack line ups. As I found out this past summer, the specs are impressive, and the marketing equally so (the gent who was responsible for much of Dimension-Polyants growth in the pack sector ran the Ultraweave rollout), which explains the remarkably fast market penetration. I’ve built packs out of Ultra 400 and 800 for myself and for clients, including a 20 liter bag I’ve used almost daily sine August, and thus far everyone has been nothing but happy.
And yet, I wonder if later this year a number of us will end up regretting being early adopters, due to fabric delamination.
This post has been kicking around 3 months, with no good answer so far as I am aware. Of most concern for me is the 3rd photo, where it seems that delamination along the stitch line is allowing the weft to slide on the warp. Ultra is a different fabric, 66% spectra and 34% poly, with spectra being notoriously slick and difficult to laminate. DX40 is another woven which blended spectra and poly, though in a very different proportion, and while DX40 suffered very asymmetrical abrasion as a result, I think the concerns are broadly similar. More acutely with Ultraweave, the unanswered question is how much dimensional stability the fabric would maintain under consistent load without the non-stretch film on the back.
Film delamination has always been a concern with pack fabrics. Every two layer laminate (i.e. no interior scrim like the VX line) I’ve put heavy use into has delaminated, at least a tiny bit, generally along seam lines. Heavy stitch penetration, especially where something is bartacked through the fabric not on a seam line, exacerbates delamination significantly. Overall this has never bothered me; even something like X33 maintains plenty of dimensional stability even without the film, and the performance gains of laminate fabrics are valuable enough for me, and my lifespan expectations for any pack modest enough. I do think the “forever waterproof” marketing claims are overwrought, if not outright disingenuous, but at the same time having exaggerated hopes for your 4-600 dollar pack is quite forgiveable. My concern is the structural concerns, something even deliberate abuse to my daypack has yet to bring to light.
It seems certain that, with the number and range of Ultraweave packs going out into the world these days, we will find out soon.