Choosing and Fitting a Rucksack or Backpack

There’s something liberating about reducing the necessities of life to the contents of a backpack. Primarily used for wilderness based activities, such as bushwalking, mountaineering and skiing, rucksacks are designed to be highly stable, comfortable to c

There’s something liberating about reducing the necessities of life to the contents of a backpack. Primarily used for wilderness based activities, such as bushwalking, mountaineering and skiing, rucksacks are designed to be highly stable, comfortable to carry for long periods and weatherproof. They are distinguished from travelpacks by their top opening, covered by a clip down lid and a more streamlined sack shape.

How to choose a backpack
There is a wide array of good backpacks available so it's important to have some idea of what you require and what to look for. You should first decide what sort of trips you will be doing for the next few years. Long trips and cold climates call for larger packs; densely vegetated country calls for a tough and slim pack without side pockets to catch on scrub. Only you can decide what you want to do, though friends can help.

Many specialised designs have evolved and they are not referred to in this general discussion. Thus with the type of use decided you are left with the three important decisions of size, design and materials.

Backpack fabrics for most Australian conditions need to be strong, durable, abrasion resistant and water resistant. The most common fabrics are texturised coated synthetics (e.g. Cordura) and canvas. Canvas used to be pure cotton, but modern materials usually have a synthetic blend with cotton/polyester for strength.

The full synthetics are more abrasion resistant, stronger and lighter than canvas, but their waterproof coatings are not as durable and the seams are usually not sealed. Canvas is a little heavier, especially when wet (although many new canvas packs have a water repellent coating to minimize this problem) but has a highly effective natural block to water penetration through the swelling of the individual fibres. Canvas can be reproofed easily whereas synthetics cannot.

Irrespective of material, no backpack is truly waterproof except purpose built packs for canyoning and boating with sealed seams. Therefore special waterproofing measures need to be taken and we recommend a pack liner (usually a large heavy duty plastic bag).

Texturised nylons: these include materials such as Cordura®. They are very strong and abrasion resistant.

Canvas: This includes manufacturer specified canvas fabrics. Although slightly heavier, canvas is more water-resistant than nylon.
NB. Many canvas packs will have nylon patches sewn over the heavy wear areas to improve abrasion resistance.

Backpack size
Both the volume of the pack (in litres) and its length are important. Some people with a big pack are tempted to carry more than is needed, but this is really only a problem of self control. If there is any chance of you going on extended trips it is better to err towards the larger capacity, provided you are not a small person. This avoids the risk of having to strap essentials onto the outside of the pack. There is no accepted standard for measuring backpack volumes, so beware that comparisons in claimed sizes are really only relevant within the one manufacturer's range. Many packs have an extendable throat that increases the useable volume, and some may include this in their measurement. Typical volumes and their uses are shown below.

  • Up to 30 litres: Good for day walking or an overnight trip in warm weather where your needs will be minimal.
  • 30 to 50 litres: Enough space for a 1 or 2 day trip. A good size for a smaller person traveling with a partner who could help carry the load of shared items on a longer trip.
  • 50 to 65 litres: Generally good for up to 3 days of overnight camping.
  • 65 to 85 litres: Can accommodate up to 6 days of overnight camping. The lower end of this range is good for most backpackers. Don't buy a backpack that is too big if you don't anticipate needing the space. The smaller and lighter your load the easier it is to travel.
  • 85 litres plus: For long walks/treks lasting a week or more.


Backpack design 
The two common types of design are those without a frame and those with an internal frame. The older varieties with a rigid external frame (usually called H or A frames and based on the old Yukon style) are still seen occasionally but have been almost totally superseded because of their weight and poor comfort.

Internals feature a narrow, towerlike profile and integrate their framework inside the pack, behind the shoulder harness. The frame usually consists of ""stays,"" or flat bars, about 2cm wide and 4mm thick. Stays are usually aluminum and are configured in a V-shape.

Alternative frame materials (such as composites) and stay-alignments (parallel, X-shaped; U-shaped) are sometimes used. Stays are usually removable and can be shaped to conform to your back.

The principle of the internal framed pack is that the back panel and the harness form an integrated suspension system. The stays make internals stiff, but not rigid, allowing the pack to move in harmony with body movements - this helps create a good anatomical fit as well. They usually have numerous harness adjustments that enable them to be modified to different backs.

The big advantages of internal framed packs are their comfort and stability. The idea is to transfer most of the load to the hips to minimise shoulder drag and pack wobble. Because the pack hugs your body, it holds your equipment closer to your natural centre of gravity and helps you keep balance when carrying heavy loads.

One disadvantage of internal framed packs is that ventilation to the back is reduced and with most designs you can expect a constantly wet shirt. The use of wicking or breathable padding on the harness can reduce this problem. Another potential problem is that the harness or frame can be vulnerable to failure and very difficult to repair in the field. It pays to buy a pack with strong stitching, reinforced stress points and a reputation for durability. It is also a good idea to inspect your backpack for possible wear points before each trip.

Frameless packs (some models include a single stay or a framesheet - see below) can store between 30 to 50 litres of gear, enough for 2 nights or more, if you are an ultralight specialist. This design is usually confined to smaller packs intended for day trips, mountaineering, canyoning, rockclimbing, etc. Frameless packs, especially the larger ones, usually have a panel of closed foam inserted into the back to provide padding. It is handy if this is removable for other uses.

Framesheet: Some internal packs place a thin but stiff sheet of plastic between you and the packbag. Often this is a material known as HDPE, or high-density polyethylene. This adds stiffness to the frame without adding much weight. Plus, it prevents objects in your pack from poking you in the back.

A frameless pack is definitely the lightest and cheapest but on the other hand requires more care in packing. There may be little or no ventilation for the wearer's back.
Features to consider on backpacks

  • Loading options: Most internal backpacks are ""top-loaders,"" where all gear passes through one big hole at the top of the pack’s main compartment. This requires you to keep quick-access items near the top. Some internals now provide zippered, slit-like openings on the sides of their main compartments that separate the main compartment into two discreet parts. This allows you to stash some items (rain jacket, for instance) lower in your pack but still have quick access to it.
  • Hipbelt and lumbar pad: Well designed and padded hipbelts represent a major advancement in pack design and greatly enhance your comfort while carrying a heavy pack. A lumbar pad should offer cushioning of the lower back from the pack. Some packs offer interchangeable belts, permitting more customised fit, and even belts where the angle of the fit can be adjusted. The hipbelt's padded ends should not touch; you need some space to be able to cinch the belt securely. On the other hand, don't tighten a belt excessively as this may irritate your hips.
  • Lid pockets and front pockets: Many packs offer pockets which are easy to reach from the outside of the pack. Some even offer elasticised ""holsters"" on the side where you can keep a water bottle handy.
  • Detachable pocket: Some internals allow you to detach the ""floating lid or front"" pocket from the pack and convert it into a bum bag or daypack. This can be a handy feature when you choose to make day trips from a backcountry basecamp.
  • Extras and attachments: Lash points allow you to attach even more gear to your pack if you feel the need. Climbers and mountaineers should look for ice-axe loops, daisy chains (a series of small loops where you can dangle gear, such as carabiners) and crampon patches. A so-called shovel pocket holds items tight against the back of your pack; it's a good place to store wet things. All of these extras, of course, add weight to a pack.

How to Fit a Backpack
Forget about the colour and the features for a moment. What really matters when selecting a new pack is making sure that it's a good fit for your body. A pack that is too short will result in a hipbelt riding up around your waist, restricting breathing. If the pack is too long, the result will be ill-fitting shoulder straps and a gap between the pack and your back. Make sure the hipbelt sits firmly on your hips, and the yoke (the place where the shoulder harness comes out of the pack) is about 5cms below your C7 vertebrae (the bone that sticks out at the base of your neck). If the pack has a foam hipbelt, its centre should rest on your iliac crest - the front-most point of your hip bone.

Most equipment manufacturers now specifically make a range of women's travelpacks. These designs take into account that women generally have shorter torsos, wider hips and narrower shoulders than men. Because women's hips are more angular than men's, they form a natural cradle for the hip belt, especially one that is wider at the bottom than the top. The pack's chest strap should lie flat across your sternum, and not interfere with your breasts or your throat.

You want to choose a pack well suited to your individual dimensions, then you need to customize it to your body shape. Here are some tips to help you:

Back length is a crucial measurement. It is important to distinguish between your height and the length of your torso. Just because you are a certain height — say a 6' female or 5' 9"" male — does not mean you automatically need a ""large"" or ""tall"" pack. Your back length, not your height, determines your pack size.

General scale to establish what size range your back length falls into:

Small: 40cm to 47cm

Medium/Regular: 46cm to 52cm

Large/Tall: 51cm to 57cm

Note: Pack manufacturers typically use general terms (small, medium, large) to identify their frame sizes; look at each pack's technical specifications to find the actual numeric range.

  • The padded sections of the shoulder straps should wrap around the crest of your shoulders comfortably and attach to the frame about 2cms below that point. No gaps should appear
  • Check the load-lifter/top tension straps. These should attach to your shoulder straps at a point just above your collarbone and just below the top of your shoulders. From there, they should rise up to join with the frame at an angle of between 40 and 50 degrees. If the angle is higher than that, your frame is too long. Any lower and your shoulders will carry too much of the load.
  • Check the shoulder strap length and width. The buckle on the strap should be far enough below your armpit that it won't chafe. The straps should be far enough apart that they don't squeeze your neck, but close enough together that they don't slip off of your shoulders during hiking. The width is sometimes adjustable.
  • Women need to pay special attention to the fit of shoulder straps. On some unisex packs, the distance between shoulder straps may be too wide, or the straps themselves are wide enough to gouge an armpit or breast. If you find a good fit is elusive, seek out a pack designed specifically for women.
  • Check for a good torso fit. If the pack fits you correctly, you should be able to redistribute the weight of the pack between your shoulders and your hips simply by loosening and tightening your shoulder straps slightly.
  • Adjust the sternum strap. Position it about 5cms below your collarbone. You should be able to breathe comfortably when the strap is fastened. It is not essential that you keep your sternum strap fastened but it may be helpful when you are negotiating uneven ground.

Some questions to ask:

  • Does the pack feel good on your back?
  • Does it pinch or bind or unusually restrict your movement?
  • Can you look up without hitting the pack with your head?
  • Can you squat down without cutting off the circulation to your legs?

Ideally, make your first trip with your new pack a short one. You can make some modest adjustments during rest stops. Over time, with regular wear, items such as internal stays and the padded hipbelt will conform to your body shape.
Waterproofing backpacks
Unless you want wet gear sooner or later, it is best to waterproof your pack. Separate items can be packed into their own plastic bags, but a better method is to line the whole pack with a large waterproof layer. Garbage bags are adequate if used in double or triple layers but will not last as long as a stronger plastic bag. These can he hard to obtain in big enough sizes, so purpose made rucksack liners offer many advantages.

Although quite expensive, they will last many times longer and will he more reliable. Some are made from heavy, reinforced PVC with welded seams and others from lighter proofed nylon with sealed seams. PVC pack liners are heavy but very tough and are recommended for heavy duty protection on canyon or river trips. Nylon is much lighter and more than adequate for normal weatherproofing. Make sure you get one large enough for your rucksack or you will face endless packing frustration. Liners are handy as a spare bag in camp if you want to split your gear.


Souced from Paddy Pallin