I now have at least 6 months and at least 100 hours of testing fairly poor quality 1.1 ounce uncoated ripstop for the main bag on my frame pack with loads up to 35 lbs. The threads within the fabric have separated a bit in places but some of that separation was present when I got the fabric. The bag still holds all the gear just fine and I'm using it every day. Here's a current photo of the fabric:



The fabric has not been exposed to abrasion on rocks or thorns. I assume it would be toast if it had been but I just don't run into things like that much.

I plan to make the next bag out of lighter nylon and see what happens over time.

Daryl,
Suppose it's better than saran wrap.
And at least it's flexible, so curved seams are doable.

It doesn't take bushwhacking to abrade a pack. A 1.9 oz. vinyl coated ripstop material abraded quickly on the top of a MYOG pack in several weeks of hiking in open country in Colorado where the worst it got was an occasional brush from a tree branch or leaves.
I think it might have been polyester, not nylon - still have some, so suppose stretching it on an embroidery hoop and putting it outside would show which, by reference to whether it wrinkles or not.

But even without more tiresome tests, nylon seems the best for packs, because of its abrasion resistance, and its suppleness and flexibility make it so easy to sew, and configure to pack shapes. But it is so hard to find nylon with a good coating that is really waterproof - the many reports on this site certainly attest to that. Since you don't appear to have issues with very high strength or abrasion, maybe the Thru-Hiker silnylon would make you a really nice waterproof pack. Some posts suggest that Ray Jardine's stuff is highly water resistant, also, and it comes in more colors. But I don't think it is as strong as the stuff T-H sells. The cordura silnylon that Lightheart Gear sells appears more abrasion resistant, but unfortunately is much less water resistant than the material from Thru-Hiker.
Or there is the Toray Industries product used by kiters called Chikara, that weighs a little less than silnylon, has a double PU coating, and is reported to be quite waterproof, even used for tent floors. Maybe Richard Nisley will test some and report on it. Not sure how stiff it is.

Unfortunately, as noted, something more abrasion resistant is needed where I hike. And the coated 70-200 denier nylons available for MYOG are not very waterproof, whether sil or PU. The packs leak after moderate use. There are some pretty nice coatings on packs at the shops, but not available from MYOG suppliers. There are the stiffer mylar laminates, but I don't relish sewing them. Tried the lightest flexible one, VX07, the needle holes were scary, and it's quite heavy at around 5 oz.

So the hunt continues for an abrasion resistant nylon under 3 oz including a really good waterproof coating.

BTW, thank you for that post last spring about the kite studio post about break tests of ferrules. May have found some for .245" I.D. carbon, like SS P400 or Victory, and will post if they pan out.

Best regards.

Edited by scfhome on 09/01/2012 21:16:29 MDT.

Daryl,
Since the previous post, I've obtained some of the Chikara material from two sources, one in France and one in the UK. It is a lightly coated material, around 41.6 gm/sq/m or 1.23 oz/sq/yd.

Whatever its strength and durability may be, it is definitely not waterproof, and in no way would I use it for a tent floor, as mentioned on a GEAR thread recently. Not unless the material used by Oookworks has an additional coating. The silnylon being sold by Thru-Hiker, although it is on the slippery side, is very waterproof, and is represented to be made of the 6,6 nylon that is more durable than other nylons. But the slightly orangy yellow, dark gray and coyote brown may not be what you want for a pack.

Although I would want something heavier for a pack, it sounds like you are totally OK with 1.1 oz nylon. Can only imagine what even "lighter nylon" you have in mind. There are a number of them on the kite sites that might be AOK for you if waterproofing is not a high priority. A list is at: http://www.para2000.org/wings/technical/inter-up.html
For example, the Skytex made by Porcher-Sport is very light in the 27 and 36 grades, has been around for a long time, is also represented to be made of better quality nylon, and can be found online. But I think it is a mistake to put too much stock in the kiting and paragliding materials if waterproofing is a priority. It would be nice to be mistaken about this, but so far it doesn't seem so.

Have had some luck recently with locating highly water-resistant if not waterproof nylons used for balloons, but they are in the 2-3 oz range, which sounds heavier than what you are looking for.

Hope that neither you or other readers were misled by anything stated in the previous post.

Samuel,

Thanks for the additional fabric info.

I plan to make my next pack bag out of uncoated M50 from Thkru Hiker.

here

I prefer uncoated breathable nylon for my backpack bags and tent floors.

Daryl

Daryl,
You might be interested in this article about paragliding fabric:
http://www.ojovolador.com/eng/read/reports/porcher/index.htm

Samuel,

That was an interesting article.

How lucky we are to have such wonderful fabrics to play with.

Daryl