We all know that silnylon can stretch quite a bit. What I'm curious about is how the material reacts if you pull on the material for extended periods of time. Will it return to it's original size? In other words, what is the elasticity of silnylon? I just made a camera bag and I want to know if it will keep it's shape if it hangs from my backpack for 2-3 weeks. If not, I may have to reinforce some parts.

Edited by Markacd on 02/05/2012 11:07:27 MST.

Good question, that also applies to the lifespans of tents and packs. Hope somebody wiser than I answers it.

When I put up a tent, it's taut

After a while it becomes loose, especially if it's windy, rainy, or colder, so I tighten it up

But then it stops stretching so I don't have to keep tightening it up, like if I camp at the same place for several nights

But when I take it down I believe it returns to it's original size because I'de notice after a while if it kept stretching - my pole would no longer be tall enough to get the edge of the tent off the ground

But, that's a tent - camera bag is much smaller so you probably wouldn't notice any stretching

"But, that's a tent - camera bag is much smaller so you probably wouldn't notice any stretching."

Despite the bag being small, the stretching is quite noticable. In these pictures there isn't even that much weight pulling on the nylon (the 600 gram camera wasn't in the bag when the pictures were taken), but you can already see it stretching. I don't really care if it stretches when I use it, but I do care if it returns to it's original state after extended periods of use.

I would definitely reinforce those attachment points, if I were you. I'm not so much thinking of the stretch factor as of the strength factor -- it's a strong fabric, but if it's going to be weight-bearing it's not a question of if, but of when the attachment point will give out!

Don't wory, it's not likely to break. You may not be able to see it, but the attachements have been reinforced.

"Despite the bag being small, the stretching is quite noticable."

I see what you mean

I think it will only stretch so much, and return to original shape

Since you've already made it, try it out : )