Backpacks

Last updated: Dec 31, 2019

Part 1: Backpack Features

Most of my trips are fairly short. The majority are only 1 night and 4 nights is about the longest before a resupply. Additionally, most of my trips are in the mountains where water is plentiful. As a result I don't need a backpack that can carry large food/water loads and a smaller frameless pack (volume ~ 35 Liters) works quite well.

I have two backpacks that are fairly similar: the Pa'lante Simple Pack V2 and the Mountain Laurel Designs Burn. Some features are better than others and neither one is perfect. The "Simple Pack" is short and wide and the "Burn" is long and skinny. The volume of the Simple Pack seems slightly less. FYI, neither one has a great fit when mostly empty, but the Simple Pack is definitely better. This is probably specific to me but I wish I'd realized this beforehand.

In the photos below I fill both packs up with the same load (tent, sleeping bag, sleeping bag, clothes, doo-hickeys etc)

Pa'lante "Simple Pack V2" (left) and Mountain Laurel Designs "Burn" (right). Both packs empty here.

filled Simple Pack

filled "Burn"

There is definitely more room at the top (for food etc) of the filled "Burn" pack. This volume difference in the main body is offset somewhat by the bottom pocket on the Simple Pack.

This is all the stuff I had in both packs. Trash compactor bag #1: 30F quilt, solo pyramid shelter with inner net and inflatable sleeping pad. Trash compactor bag #2: clothes (light down jacket, baselayer top and bottom, beanie, liner gloves), toiletry bag, polycro sheet, mylar space blanket, tent stakes. Yes. I do regret not making the trivial effort to arrange/organize pack contents for the photo. As is, it looks like a racoon raided a dumpster...

The 150D DCF material for the body of the Simple Pack defnitely seems more durable than the Burn. However, I'm not sure this is necessary even for all the bushwhacking I do.

The perfect bushwhacking/scrambling daypack?

Ultimate Direction Fastpack 25. (Here I'm drying out my shoes/socks/gloves. And eating health food).

A while back I picked up the Ultimate Direction Fastpack 25. I was envisioning it as a daypack but I picked the 25L version so I could use it on really pared down overnight trips in mild conditions. Ultimate Direction markets primarily to the running community but I definitely think they're on to something. The vest system (with two sternum straps) really gets the perfect fit that stays put.

Clearly, they developed this for runners but it's PERFECT for scrambling and even serious bushwhacking like jumping over deadfall since their isn't any sudden change in center of gravity as you move. The straps themselves don't have any padding (actually mesh in the center) but the fit is so great with the sternum straps I've never felt the need for more padding.

They've also implemented tons of storage space on the straps themselves, which is perfect for keeping things accessible while walking. This includes snacking (or even "mealing"), checking maps, taking pictures from with easily accessible camera etc.

An interesting perspective from "Neemor" regarding what makes a good pack. He's right on and makes his point well. His youtube channel is pretty good on the whole.

Part 2: Backpack Fabrics

I recently bought a sewing machine and am going to start making my own backpacks because I can never find the exact features I want. Eventually this material will be moved to a MYOG (Make Your Own Gear) page, but for now it stays here. To be honest, most of the material below is basically notes I've made for myself as I learn the difference between Dyneema, X-PAC, DCF, Robic, Ballistic Nylon etc.

Fabric Construction

Today, most fabrics are made by interlacing fibers to form a sheet. The two primary methods for interlacing are knitting and weaving.

See also: https://www.britannica.com/topic/textile/Production-of-fabric

The difference between woven and knit fabrics. Knit fabrics are made of a single yarn, or fiber, that are looped together to make braids. Woven fabrics are composed of many different fibers, intersecting at 90 degree angles. The primary benefit of woven fabrics over knits for outdoor gear like backpacks is suggested by the photo on the right. One loose end will cause a run quickly causing the fabric to unravel.

The three basic motions of the weaving process on a loom.

The two components of a basic weave, the warp and weft. The fabric will not stretch in the direction of either the warp or weft unless made of elastic fibers. Here the warp and weft fibers have different thicknesses (see discussion of Denier below).

A basic plain weave (cotton canvas)

Various weave types.

Various weave types for wire cloth! Image from the Neward Wire Cloth Company.

Outdoor backpacks: historical context

The first backpacks were made of thick canvas (cotton) with a heavy wax coating for waterproofing. These packs were incredibly durable but were heavy, retained lots of water and were prone to rot if they were stored wet. Modern backpack fabrics use the same basic principle newer and better materials. Now, virtually all premium backpacks are made of woven nylon and are coated on one side with either polyurethane or silicone to improve waterproofness and abrasion resistance.

Fabric coatings

Fabric coatings generally, increase durability, abrasion resistance and waterproofness. These benefits come at the expense of decreased breathability and increased weight. Both silicone and polyurethane coats can be applied to the individual fibers themselves (before weaving them into a fabric) or to the bulk fabric. Typically, coating the fibers themselves is the preferred method because of better breathability, a better coating longevity.

Fabric Denier and Weights

If forced to pick a single metric for backpack fabrics it would be thickness. This is typically quantified in two ways: in term of the (1) individual fibers (Denier) and (2) the weight per unit area of the aggregate fiber (weights). This wikipedia article of textile measurements is a useful for disentangling this information.

Denier: A measurement of the linear mass density of individual fibers.

As a unit, the "Denier" or simply "D" is the mass in grams of a 9000 meter length of a single fiber. For a sense of scale consider these two extreme examples. At one end, the shell fabric of ultralight down jackets like the Mountain Hardwear Ghost Whisperer are made of 10D nylon. On the other extreme, heavy duty nylon work clothes such as Carharrt's Cordura Duck are made from 1000D nylon. Guess which one of these is going to be more durable?

Weight: This measurement refers to the mass per unit area of the aggregate fabric.

Units for fabric weights are (g/m^2) or (oz/yd^2). Since I suspect most people reading this are from the United States, where we refuse to embrace the metric system, most of the discussion will be in imperial units (sigh).

Weave Patterns for Backpack Fabrics

Basic nylon fabric turns out to be fairly delicate. Once there is a tear or puncture in the fabric, the lack in tensile strength makes it prone to a continuous rip along the initial tear. This can of course be remedied by using higher Denier fibers throughout but it is inefficient. Manufacturers will often combine fibers of different Denier into different geometric patterns to improve abrasion resistance and tear strength, while retaining low fabric weight. .

Nylon Packcloth:

Ripstop Nylon: a lightweight nylon fabric with interwoven reinforcement threads in a cross-hatch (grid) pattern.

The heavier threads will stop the rip from running all the way to the edge of the fabric.

(Leftovers from edits--will be fixed soon)

Backpack fabrics are sold under brand names such as Cordura, Dyneema, Robic and X-Pac. Sometimes cuben will also be laminated to other fabrics to improve abrasion resistance. Some manufacturers such as ZPACKS, Hyperlite Mountain Gear and Mountain Laurel Designs are well known for incorporating this feature in their packs. Andrew Skurka has pointed out that while cuben fiber is a good choice for ultralight shelters, it's not the best for backpacks, especially if you do lots of bushwhacking. It will be interesting to see how the Simple Pack holds up over time.

Cottage Backpack Companies

Mountain Laurel Designs: https://mountainlaureldesigns.com/
Palante Packs: https://palantepacks.com/
ULA Equipment: https://www.ula-equipment.com/
Hyperlite Mountain Gear: https://www.hyperlitemountaingear.com/
CiloGear: https://www.cilogear.com/
- These packs look interesting for winter.

MYOG/DIY thread

Thread manufactured by Gutterman thread seems to be the standard choice for outdoor gear. The two most common varieties are Mara and Tera. Both are made of 100% polyester. The info below is copy/pasted from a hammock forum thread (see below).