pack fabric: 140D or cuben hybrid?

There are two ways a pack could fail.

1. Seams ripping – This is going to be caused by either the thread or the fabric around it ripping. For lighter loads both fabrics are plenty tough. The real question will be whether you do the stitching neatly with the right thread.

2. Fabric ripping – Both fabrics should be fairly tear resistant. I'm pretty sure the Cuben hybrid would be less abrasion resistant. So if you plan on dragging it over rocks I'd go with 140D (or 210 D). Otherwise I'd guess they'd be about equal.

Both of those are kinda pricey fabrics. I'd try some Xpac first. Its a bit heavier but perfectly good and cheaper. Don't use the heavier Xpac for starps or hipbelts however, its too stiff.

Out of these two fabrics, the real advantage of the cuben hybrid is that it's basically waterproof. If you hike it wet locales or packraft then that's valuable. If not, I'd go 140D because they're close in weight, the 140D is cheaper and it's got a nicer feel to it. If you go cuben hybrid, I'd look at the 3.3oz out stuff rather than the 2.9, because that has a significantly more substantial outer polyester layer.

200D Oxford from owfinc.com is $5 a yard. Maybe 4 ounces/yd2. Other places have similar. If a pack takes 1.5 yd2, it might weigh an extra ounce or two. That will never fail. But the cost of the fabric isn't that much more because you don't use very much and maybe you should use the good stuff if you're going to spend your time making it.

The hybrid stuff is more bomber by a significant margin IMO.

thx