I wouldn't trust glue for an exterior environment or for any strap that has nylon in it.
I take it you're not a sailor then, Brian ? All modern boats are either made or held together with epoxy or polyester resins, and with very few exceptions all cordage is now synthetic.
This is true LJ but the strength member is fiber glass or carbon fiber not nylon. Some synthetics can be glued, nylon is not one of them. Silicone rubber would be the best choice for gluing fabric because it can flex. Epoxy would be the last choice because it doesn't flex very well. Sewing is by far the best choice followed by stapling or riveting and then wrapping the joint with vinyl tape.
Nope, I am not a sailor but I have sailed. I would think all sailors would know how to sew.
I don't know how nylon got into this topic - not from me I can assure you.
Although webbing may all look similar, there are a few key differences between the three types of heavy duty webbing we sell. What works for one application, might not work for another. For example, for use as a recovery strap, choose nylon. Webbing ratchet in polyester will work better for tie-downs as it has less stretch than nylon.
Polyester webbing
Polyester?s lower stretch value makes it ideal for tie-down applications. Sometimes called military webbing, polyester cargo web is strong and lightweight like nylon webbing, but without the stretch of nylon. Its strength and flat profile makes it useful in some applications in place of traditional rope.
http://www.uscargocontrol.com/Webbing
And - just as all nylons are not the same, epoxy (which is only a name derived from a particular type of chemical bond) glues are also not all the same. For gluing polyester webbing, I use an epoxy which remains very slightly flexible. And, we're only talking about a short length anyway.
Yes, I can sew - some of my sail repairs (done by hand, not machine) are works of art. Well, at least I think they are.
But for a tie-down just to hold a few boxes together ... I'd go for the quick 'n' easy option every time.
LJ