Hi all,

It’s my perception that thru-hiker’s Momentum fabric and good ol’ 1.1 ripstop are the primary breathable nylon fabric options for ultralight diy gear-makers. Unfortunately, I’ve yet to find a comprehensive source of information comparing their properties. Web and forum searches have turned up most of the information I might want, but there are still some gaps and ambiguities. This post will list what I think I know and what I would still like to know. Readers are invited to correct my mistakes and clear up my ignorance. If you’re curious why I write and think like I do, I’m an engineer/scientist, so I can’t help it. :)

Momentum:

Momentum 0.9 is a single-calendared, 20dx20d nylon fabric with a very effective DWR coating and a finished weight of ~1.05 oz/yd^2. It is available as a tafetta or ripstop. The tafetta is generally used as a liner, the ripstop for outer shells.

Per AYCE, compared to [thru-hiker’s] 1.1 ripstop, the Momentum ripstop has comparable puncture/abrasion resistance and slightly enhanced tear strength.

Being single-calendared, there is a shiny (calendared or “heat-treated”) side and a matte side to the fabric. Per AYCE, the matte side is the “right side”, i.e. goes to the exterior of the sewing project. Based upon this, I’m ASSUMING the DWR coating is primarily applied to the matte side. (If this is not the case, and both sides are comparably water-repellant, I’d be interested in whether water beads more readily on the shiny side or the matte side. For cold-weather use, where condensation can be an issue, I would generally prefer to keep enhanced bead formation on the exterior side.)

1.1 ripstop

There are many varieties of 1.1 ripstop out there. The effectiveness of their DWR coatings likely varies. Per AYCE, the finished weight of [thru-hiker’s] 1.1 ripstop is 1.3 +/- 0.1 oz/yd^2. (For comparison, I recall waterproof silnylon weights quoted as 1.35, 1.4, 1.5 oz/yd^2, again likely reflecting the variety of material available in the market.) The thru-hiker 1.1 ripstop is listed as a 30d fabric. 40d fabrics are also available from various sources, but many fabric shops don’t specify, so the buyer is left to guess. I’m ASSUMING most of the 1.1 fabrics we use are double-calendared. Calendaring seems to increase strength, increase down-proofness, increase water resistance, and decrease air permeability. If double-calendared, there would generally not be a ‘right’ or ‘wrong’ side to the fabric.

A post on hammockforums.net SUGGESTS that 30d ripstop is constructed from nylon 6.6, which is stronger than nylon 6. (I do not know what variety of nylon is used for Momentum.) Specifically, it was suggested that 30d ripstop from nylon 6.6 is suitable for constructing a single-layer hammock, while more generic 1.1 ripstop made from nylon 6 lacks sufficient strength. (70d 1.9 ripstop is the typical fabric recommended for single-layer hammock construction, but 1.1 is commonly used for double-layer hammocks. Although quite strong due to the silcone coating, 1.1 silnylon would have ventilation issues.) Note that the lightest commercial Hennessy hammocks are constructed from a ‘high-tenacity 30d nylon ripstop’, corroborating this suggestion. (If all this is true, and Momentum has even higher tear strength… but I’ve never heard of someone making a hammock from Momentum.) In addition to tear strength, fabric stretch is also a concern in hammock construction. Some may find a single layer of 1.1 ripstop too stretchy for comfort, even if it is strong enough. (I do not know the stretch characteristics of Momentum.)

Comments on the backpackinglight myog forum from Ron Bell of mountainlaureldesigns suggest quilts made from Momentum are warmer than those made from 1.1 fabric. I infer this is because Momentum’s tighter weave and more effective DWR treatment results in reduced air permeability. I had previously ASSUMED Momentum is more breathable than 1.1 ripstop because it is single-calendared, but if it is less air-permeable, I could have been mistaken. (Part of this confusion could also be due to the variety of 1.1 nylon fabrics out there.)

Any corrections and clarifications would be appreciated.

Cheers,
Craig
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Various sources of information:

http://www.hammockforums.net/forum/showthread.php?p=76987
http://www.articlealley.com/article_178753_22.html
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=2479
http://www.backpackinglight.com/cgi-bin/backpackinglight/forums/thread_display.html?forum_thread_id=12101
http://www.mountainlaureldesigns.com/fabric.php
http://www.thru-hiker.com/x/index.php/forums/viewthread/187/#631
http://www.thru-hiker.com/x/index.php/forums/viewthread/72/
http://www.thru-hiker.com/x/index.php/forums/viewthread/68/
http://www.thru-hiker.com/x/index.php/forums/viewthread/40/
http://hennessyhammock.com/comparisonchart.html

Hi, Craig,

Purely subjective, but I have a quilt made of ripstop and another made of Momentum. The Momentum feels much better to sleep against (softer, less “scratchy”). Can’t comment on warmth as they are not of the same design.

I am constructing a hammock and trying to decide what fabric to use for the hammock body.  Are any of the fabrics sold by thru-hiker made from nylon 6.6 instead of nylon 6?  My understanding is that even 1.1 ripstop in a single layer is sufficient for a hammock if made from nylon 6.6.  And what about momentum?

Our 30d 1.1 oz breathable is a parachute textile and is made from nylon 6.6, while Momentum is an apparel textile and is made from nylon 6.

I have made a Liberty Ridge jacket out of the Momentum ripstop and 1.1 Ripstop.  I have used each on hikes in the Southern Appalachians (humid).  Hands down, the momentum ripstop feels softer.  However, it also feels less permeable than the 1.1 ripstop and I sweat faster in it than the ripstop 1.1.

I tested the porosity of three fabrics recently by simply pouring 2 fluid ounces of water in a pouch on each of the following 3 fabrics:

Left: $1.50 Walmart Ripstop I found in a Boone, NC walmart (clearly more porous and lighter than previous $1 rs from Walmarts)
Middle: 1.1 Ripstop 1st from Thru-Hiker
Right Momentum Ultralight Ripstop from Thru-Hiker

After one hour, ~1/2 of water leaked through the Walmart ripstop while none of the water came through the 1.1 Ripstop or Momentum.
In a previous test I did with the momentum and 1.1 Ripstop a few drops leaked through both fabrics after a few hours.

Is there another appropriate test for the breathability of these fabrics?