Packs - of all sorts

Send any comments to the maintainer Roger Caffin

Go into any bushwalking shop and you will find a bewildering array of packs for sale. Are they really all different? Well, not much. Sometimes it seems that every would-be gear maker starts by making a new line of packs, which would be interesting if they weren't always pretty much the same. Sadly, many of them seem to copy the wrong ideas about pack design.

There is usually a huge range of day packs on display as they sell very well to the general public - but many of the cheaper (Asian) ones are supposed to be really only meant for street or school use. Telling them apart may not be that easy for a novice: the surface differences are not great. Actually, some of them aren't that bad for the price, if you just want a simple day pack for easy trips.

There usually seems to be a huge range of larger packs, but again there are only small number of differences here. You have single and double compartment packs, and you have packs for a number of different activities, but there are lots of choices for each category. There is a large range of manufacturers, so often there are several brands available in any shop for each application. In addition, packs are made from different materials - and in different countries to different standards of design and construction. Some manufacturers try to come up with distinctive styles, while not really deviating from the perceived "standard", so they all look pretty similar underneath.

How do you choose the right pack from all this? Some general comments can be made: "you get what you pay for" or "ygwypf" (you knew that was coming, didn't you?), "comfort, comfort and comfort" (3C), "ask the sales person in the bushwalking shop" and "ask an experienced friend". Many of the staff in the shops are fairly experienced walkers themselves, and generally give good advice - but remember their aim is to sell you a pack. Ask other walkers what they think of their own packs. Most will be very happy to tell you - at some length.

Packs in General Pack Details

Other Pack Issues

 

Pack Design - History

A pack is a means for carrying your gear: all else is detail. But in looking at the details, remember the two rules of "Ygwypf" and "3C". By and large, for us a pack is a bag with shoulder straps which we carry on our back. Some cheap packs fall to pieces; badly designed ones are a pain. On the other hand, don't always blame the pack. One day I found that my pack was really creating a pressure sore at the centre of my back, no matter how I adjusted the straps. Eventually I stopped, opened up my pack and moved the edge of the hard gas container away from where it was sticking into my back: instant relief. Equally, some of the cheap Asian day packs would do quite well for many day bushwalks.

Things get a little more complex when you look at the larger packs: ones suitable for several days walking. The pack has to have some sort of structure to transfer the load from the pack to you, preferably to your spine since that is your principle load-carrying structure. No, the load is not carried entirely on your shoulders and hips - or should not be. A lot of it should be carried on your back (but not pressing directly on your spine). However, this does not always happen as the evolution of the Australian bushwalking pack has followed a strange and not very logical path, which we will briefly list here.

The first Australian packs were actually swags: a blanket roll containing some gear, slung over the shoulder, and carried by swaggies. A rather sophisticated version of this was developed by Myles Dunphy and Herb Gallop, and is shown in the picture of Myles to the right (picture copyright Jim Barret). It was called the Dungal swag after the two of them. You will note that the main load behind Myles is balanced by the food bag at the front. This allowed Myles to walk upright rather than bent forward: a far more comfortable position than some 'modern' packs require. However, this design does have problems in thick scrub and on steep rocky territory.

The next pack we had was probably the small rectangular army knapsack left over from the wars. I carried one of these once on a walk, but it was far too small and horribly uncomfortable, and I have no idea how the foot soldiers managed. One assumes they were not asked what they thought of it. Officers did not carry packs of course.

After the war Paddy Pallin introduced his famous A-Frame pack, in several models. It was a lot better than what had been available before, and the Bushwalker model with lots of pockets is shown in the picture to the left (photo of and courtesy of Jim Barrett again). I have carried one of these packs (the two-pocket Federation model) for many miles, and many of us will remember it well. However, while the picture shows the wearer standing up straight, the normal walking position was bent forward from the waist quite severely. It appears to have been modelled on a Norwegian pack of similar design, but that pack was designed for ski-touring, not walking. It had to have the weight very low and the shoulders free to twist for the old Alberg style of skiing. Bluntly, the purpose of original design was misunderstood and the weight was put far too low down for a load-carrying walking pack, and that put a huge strain on the shoulders and the back. It was not a comfortable pack, especially with any serious load in it. Those outside pockets pushed the load yet further still from your back. The upper part of your body ended up bent way over towards the horizontal. It was a real relief to get rid of it at the end of the day, and rest your aching back and shoulders.

Then there were two H-frame packs: the Flinders Ranges and the Mountain Mule. There is a picture of a Mule a little way down. (Good photos would be appreciated!) These were roughly copied from the H-frame packs used in America to transport quite large loads, but unfortunately the Australian and New Zealand designers once again misunderstood the basic design. They made both of these packs too wide and too short: the frames were almost square. The original idea was to transfer the load to the frame, and then have the frame transfer the load to the wearer's back. To be sure, these carried the load somewhat better than the A-frame pack, but not well enough. The short frame meant the load was not properly transfered to your back. The excessive width meant many wearers suffered regular bruises to the arms. There was still (a lot of) room for improvement.

Now we have the modern 'internal frame' pack, introduced in the late 80s. This appears to have been copied from the European alpine climbing pack, with lots of modifications and additions in the harness and frame section to try to make it a successful bushwalking pack. Sadly, once again, the manufacturers have got it wrong. To be sure, alpine climbing sounds glamorous, but so what? For climbing you need the load down low so there is not as much drag on your arms, especially when you lean back to reach for a handhold. This is the opposite of where all good load-carrying arrangements put the load, as explained below. And climbing packs need to be round with no protruding things to catch on the rock when being hauled up the cliff, so any frame has to be internal and is severely compromised as a result. Sadly, the glamour of the 'alpine' cachet and marketing won over functionality.

The consequence is that manufacturers of internal frame packs still spend a huge amount of effort continuously redesigning their 'harnesses' in an attempt to get the load carrying right. But the more complex the harness, the further the load is from your back, and the greater the load on the shoulders. This is compounded by the popular myth that a harness must have a gap between itself and the wearer's back, for air circulation. More structure, and more distance between the load and the wearer. And, of course, the greater the weight of the harness itself and the greater the cost of that harness too. Sadly, none of the manufacturers seem to have stopped to really examine just what they are doing with this design and whether they are on the right track. Perhaps they believe that the public would not buy anything else now? Maybe.

 

Theory of load carrying

Just look at this poor guy. He has got to be uncomfortable with that pack dragging back on his shoulders, but why? Well, obviously he has got his pack all wrong, but how should it have been be arranged? For that matter, what makes a good pack design, and why? We could go on at great length about the theory of load carrying, pack design and erggonomics, but it would slow down the loading of this page. Rather than skip all that good stuff it has been moved into a page of it's own: Pack Theory. Basically, that page brings into serious question many of the 'designs' currently on the market. They are more style and glitz than functionality. We now return you to an equally important matter.

 

What weight can you carry

Just as important as how to carry a load is how much load can you carry. Some might say it is even more important, and certainly how you carry a load may limit how much you can carry.

One of my mountaineering books tells a story of hut building on the border between Switzerland and Italy. Guides from both sides were involved, and competition was natural. One Swiss guy was reputed to be extrordinarily strong, able to carry huge loads up the mountain. And so the Italians watched with great interest as he shouldered the cast iron stove for the new hut and started up. Some way up it became clear that he was struggling a bit, and one Italian was moved to offer some sympathy over the weight of the stove. Sympathy, or maybe a delicate needle? The Swiss guide replied that the stove was no problem, but the full sack of flour inside it was a bit heavy! [If anyone knows the book and page for this story, please remind me!] But while there are plenty of good stories, let's be realistic and remember that this is bushwalking, and we are doing it for fun. You should not be carrying a huge load which makes you lose all sense of enjoyment in the outing. So what loads can be carried reasonably? The following couple of paraphrased quotes cover some actual Army research and experiences - although the author also bemoans the fact that the Army (any Army!) tends to ignore all this reasearch in practice.

One of the studies was conducted by Institute William Frederick in Germany in the last few years of the 19th Century. The Institute was particularly interested in measuring the effect on infantrymen who were carrying different loads under varying conditions of temperature. The research demonstrated that in cool weather a load of forty-eight pounds could be carried on a fifteen mile march by acclimatized soldiers that were in good physical condition. However, in warm weather the same load produced an impairment of physical strength, and the soldiers did not return to a normal state until some time during the next day following the march. The Germans then increased the weight of the load to sixty-nine pounds and discovered that even during cool weather the soldiers in the experiment had obvious physical distress. During this phase of the study the Institute attempted to determine if physical conditioning with the same amount of weight would make a difference in the individual's reaction. The results were very interesting, demonstrating that he continued to show physical distress in an equal amount regardless of the degree of physical conditioning. "The conclusion was therefore drawn that it is impossible to condition the average soldier to marching with this much weight no matter how much training he is given." [48 lb is about 30% of a typical soldier weight of 160 lb.]
The Germans subsequently determined after experimenting with varying weight amounts on forced marches that the absolute limit under the pressure and fatigue of combat was forty-eight pounds per man.

The commission pursuing the research for the British Army expended most of its effort in determining physical ailments resulting from the infantryman being heavily burdened on long marches. In general it discovered that armies in the past had on the average issued the soldier between fifty-five and sixty pounds, and by means of training marches tried to condition him. The commission finally reached the conclusion that..."not in excess of forty to forty-five pounds was a tolerable load for an average-sized man on a road march. More specifically, it stated that on the march, for training purposes, the optimum load, including clothing and personal belongings, is one-third of body weight. Above that figure the cost of carrying the load rises disproportionately to the actual increment of weight."

The USAIS proceeded with its research based on the following data. Firstly, studies indicated that the fiftieth percentile soldier weighed 160 pounds. Secondly, field tests demonstrated that the ideal soldier's load was thirty percent of his body weight, or forty-eight pounds, and that the maximum load a soldier could carry should not exceed forty-five percent of his body weight, or seventy-two pounds.

Taken from http://www.globalsecurity.org/military/library/report/1985/IDC.htm with acknowledgement.

So a figure of 30% of body weight seems to be what a soldier can carry and remain functional. I agree with that figure for soldiers, but I would point out that 'soldiers' are young, strong and under orders. They are not meant to be enjoying themselves. For the rest of us, I suggest 25% of body weight is a reasonable upper limit. I weigh 64 kg, and 25% of that is 16 kg. I find that loads under this do not affect me very much, but over that I have to put my head down and slog. If you are female and lighter, take note! You should look to limiting your load to even less than 25% if you want to enjoy the bushwalk. Dare I suggest that this is an opportunity for the males of the party to prove their machismo, by helping?

 

Current Bushwalking packs

Since this is what is available on the Australian market, this is what most of us are stuck with. So let's review what we get for a typical bushwalking pack. There is an adjustable 'internal' harness on the outside - that's the bit with the shoulder straps and the attachment to the bag. It often includes metal strips threaded into the back of the pack for shaping the pack to fit your spine. All this is meant to allow the pack to be fitted to match your back, and to some degree this can be quite important. If you buy one of these packs, make sure the sales person spends some time with the adjustments and shows you what they do, why they do it, and how to adjust them.

One common problem is having the shoulder straps too long, or the top or 'balance' straps too long. The result is the pack leans away from your shoulders, and the drag becomes very noticeable - as shown in the picture of the guy in the snow. The shoulder straps often ride on metal strips down the back of the harness. These should be bent to roughly match your spine. The strips don't have to follow the curve of your back exactly, but the tilt at the bottom of the pack should match the tilt of your bottom, as it were. You don't want it digging into your gluteal muscles. At the same time make sure the harness itself does not rub directly on the bones of your spine: 8 hours later that little rub can become agonising. One imported pack I tried had a thick arrangement of Velcro holding the shoulder straps to the bag near the top: it was so thick that it made its own pressure point on my spine just below my shoulders. Eventually I modified it (removing several redundant layers of Velcro and Cordura) so it didn't stick out, and the pack became comfortable.

What I haven't pointed out yet is that the 'internal farme' design was originally developed for alpine climbing, where you want the weight low to take the strain off your arms, and are not doing a lot of distance. Alpine climbing is very glamorous of course, but that is not what is really wanted for bushwalking, which involves carrying a load over a fairly long distance. Yes, I know the vendors all hype their internal frame packs and the harnesses - they would, wouldn't they? In reality, they have just blindly followed each other down this path. A pity.

Because the 'internal' frame pack is a poor design it is hard to make it really comfortable. So the metal strips serve a second purpose: they allow the contact point for the shoulder straps to be adjusted in height. Well, that's the theory, but few walkers know how to do this, and over a small range it does not really have much effect anyhow. Manufacturers have to make several pack sizes anyhow to cater for the range im humans; at least one manufacturer simply made different sized packs and didn't bother with any adjustments down the back. He swore the results were just as good, and lighter and cheaper. But then again, an adjustable frame is good for the marketing hype.

A little air gap down the back is supposed to be useful in hot weather (they say), but no matter what sort of pack you have your back will get hot and sweaty. Face it, accept it, and move on. Anyhow, in winter I find the pack makes a very nice insulator on my back: I don't want lots of ventilation there. Anyhow, I am not convinced about all the truth of the claims for "ventilation" some pack makers trumpet: everyone gets a sweaty back carrying a pack. More marketing hype maybe.

The stiffening needed to hold the pack in shape can come from the shape of the pack itself. If the sack is essentially a tube and you fill it fairly tightly, it may not need those thin bits of aluminium strip to hold its shape. Have a look at any large day pack to see this. On the other hand, good large packs usually have a solid bar across the top, attached somehow to the attachment point for either the shoulder straps or more likely the balance straps. This bar is really a key part of the whole 'frame' and the means of linking the straps to the body. Often, this bar is not obvious until you look for it. Sometimes there will also be some stiffening at the bottom of the pack behind the waist strap. Why don't they just make an explicit external frame?

While an adjustable frame pack can be tailored to fit you, there are limits to how well it will fit. If it is too big (or too small) for your spine, it will never be really comfortable. A pack made for someone over six foot (sorry!) just won't fit a small woman. So, despite all the adjustments, you may find that a particular pack just does not feel comfortable. It's made for someone of a different shape from you: don't buy it. Find one that is comfortable (3C). Some manufacturers make a particular model in different sizes: try a different size.

Pack Size

This is a trade-off. You don't want to find that the pack you have just bought isn't big enough for your next trip, do you? However, this worry is a bit of an illusion. Consider a "large" 90 litre expedition pack: 90 litres of water weighs 90 kg. A large pack presents a serious risk of overload, simply because "there is room for it" and you aren't forced to seriously asked whether you "really need it". Further, most females should deliberately choose a slightly smaller pack because they have less upper-body strength than males. And what is male machismo for, anyhow?

A 60-70 litre pack should be quite enough for trips of a few days, up to a week in fact. But be careful that what you have chosen has a harness which fits you. You will find that the harnesses on some cheaper imported packs don't carry a load quite as well as good Australian and Kiwi packs. That is not a reason to reject an imported pack if it fits well: just keep the load down. I have a Tatonka which is fine up to 16 or maybe 18 kg, but I wouldn't want to put much more than that in it. A Macpac Cascade can carry over 25kg fairly easily - although you may have a lot of trouble standing up when it gets around 30kg. This classic pack puts a lot of the load fairly low, and this is good for climbing.

Many packs come in several sizes or back-lengths. I am not going to try to describe here what pack length you need for your back: that is best done by an experienced sales assistant in a good bushwalking shop. It is a moot point which is worse: too short or too long. Either way the big bum pad and waistband are not going to fit where they should, between the coccyx and the small of the back. Too long and the pack restricts the muscles in your backside; too short and the pack drags on your shoulders. Fortunately, good internal frame packs do have some length adjustment in the harness, and sales assistants should be trained in the adjustment. But it can still be worth while trying out small adjustments in the field yourself.

Day packs

These generally do not need a frame, but they should have a padded back and a top closure. Good brands come in a range of sizes to suit each walker. A 30 litre size should suit most day walks. The waist band may be rather nominal. It would be nice to say these are cheap enough that you can afford to experiment, but this is not so - at least with the good ones.

In this category you will also find hordes of cheap school kid packs. Ygwypf. You will also find cycling packs, climbing packs, travelo packs and so on. Each of these is optimised for one purpose at the expense of other functions, and this often makes them less suitable as a general walking day pack. It is worth asking the shop assistant for what you want, or what they think a particular model is best for. Note the cautions given above about zips.

Quite a few day packs have all sorts of extra fixtures on the back. In general you simply don't need two ice-axe fittings and crampon straps in the Australian bush. Nor do you need reflector tape and Day-Glo decorations. But a hard-wearing Cordura bottom to the pack is pretty much essential.

One pack which has given a lot of very hard service to us is the Berghaus Dart 30.

Overnight and expedition packs

These usually have a frame and come in sizes from moderate (say 50+ litres) to extreme (say 90 litres). Note the comments above about the risks of huge packs and overload. The pack must have a comfortable frame or harness and a reinforced bottom. A waist band is considered essential on an internal frame pack to get some of the load off your shoulders. The bag should look reasonably shower-proof when done up. This usually means a good flap over the top. A small external pocket on the lid or back can be very useful for small items like glasses, cameras and so on. As mentioned before, pockets on the sides simply get in the way in the scrub and should be avoided. Strap-on extra bags, bum-bags and day-packs are "travel market" frills you don't need.

The shoulder straps should obviously be adjustable. There should also be small adjustable straps at the top of each shoulder strap, going back to points high up on the pack. Some call these "balance straps", but the terminology doesn't matter too much. On the other hand, correct adjustment of these does matter very much. If those straps are loose the pack will drag backwards, and it will look as though it is dragging backwards too. The guy in the snowy picture above has a bad case of 'backwards drag'. If only one strap is loose the pack is going to feel rather lop-sided. Get someone experienced to show you how to adjust these if necessary: it is well worth while. Sometimes these straps seem to be far too long, but that is for a reason. They can have large loops at the ends: these are very useful for grabbing with your hands. Doing this seems to take a bit of the load off your shoulders. Large loops are best here: if you fall over you need to be able to let go quickly. Alternately you can have grab loops attached to the shoulder straps themselves.

Some packs also have adjustable straps on either side at the waist, between the pack and the waist band. These alter the shape or curvature of the waist band and control how much the pack sways from side to side. However, they usually are not that critical. Increasing the curvature may help a waist strap fit a female bottom a bit better: they seem to be more shapely than male ones.

Most harnesses on large internal frame packs have an adjustable strap across the chest called the sternum strap. This is not (really) meant to be load-carrying: it is meant to control the position of the shoulder straps on your body, and can contribute to ease of carrying on an internal frame pack. On an H-frame pack it is not needed. Doing it up too tightly will probably limit your breathing. Getting it too high will do likewise. Finding where to put this strap can be a problem for some females. Don't try hanging things off this strap: they make you very sweaty, bounce all over the place, and fly everywhere when you unclip to drop the pack.

Some packs have mesh pockets on the outside. I am not sure I would trust any vital gear to such pockets, and whatever you put there will get wet when it rains. However, they could be useful for holding wet socks and underwear on long trips: a sort of travelling clothes line (been there, done that.)

Some refinements on some packs are getting a bit technical and are not really necessary; other seem designed more for glamour (=marketing) or street use and are completely unnecessary. Ice axe straps and crampon bindings seem a little out of place in the Australian bush, but are relatively harmless. Some shoulder straps have D-rings on them, high up in front. One can hang a camera case off these, although it can get in the way. They were originally put there to hold a carabiner, so you could hook your hands onto your shoulder straps ('grab straps'). They are harmless, but few need carabiners there. Webbing loops would be better. On the other hand, things like reflector tape are just marketing glitz, but you are paying for it. Attaching such useless tape to the pack usually means more holes through the material for water to get in. And lots of extra external pockets are more marketing glitz.

Ultra-Lightweight Packs

These are a bit specialised. The lighter the gear, the farther you travel, but the shorter the life if you mistreat it. While a conventional internal frame overnight pack can weigh 2.5 kg quite easily, full-size ultra-lightweight frame packs come in closer to 800 gm. Good ones work very well. They are covered in the Ultra-Lightweight FAQ. The author makes his own and uses one all the time. Apart from saving about 2 kg in weight, it is more comfortable.

You will also see a fair bit about even lighter packs in America, down to a few hundred grams. Some of them look very glamorous, but several words of caution are required here. First of all, these American UL packs have no frame at all, and are only meant to carry very light loads. They come out looking like round balls when full, and their ergonomics are terrible with significant loads. Actually, their ergonomics are not very good anyhow, but you don't notice that if the load is light enough. There is more on this in the Pack Theory section. The second problem lies in the materials and construction needed to get these very light weights. The fabrics are extremely light and can be shredded in the Australian scrub. (They can be be shredded in American scrub too.) In addition, the stitching can't be very strong when the fabrics are so light, and it has been known for the shoulder straps to tear out and disintegrate under load. These packs are meant for fanatic ultra-lighters on short trips, and for 'adventure racers'. They are good for their intended applications.

Canyon packs

These are a bit different from other packs; They are meant to be thrown in the river and used as floats. They must be waterproof! They get bashed against canyon walls and dragged up and down them, so the fabric and design must be smooth, without bits to catch on things. This means they are usually made of fairly heavy-grade welded PVC-coated (or PU-coated) fabric with a special roll-down seal at the top, and no other external fittings at all which might catch on any rock. Well, pity about the shoulder straps. They are not cheap, but can make the difference between a dry lunch and jumper and a completely soggy mess. On the other hand, they are seldom as comfortable to carry with any large load in them, although I sometimes think this is as much due to the shape of the loads they have to carry. For this category you should examine other peoples' packs and get specialised advice.

A very common substitute, which is highly recommended, is to buy a waterproof canyon liner or "dry bag" (without shoulder straps). Again, the dry bag is made of medium-to-heavy PVC fabric with a roll-down seal: it's just a bit lighter. You put it inside your ordinary day pack (or overnight pack for really serious stuff) with all the "dry" things inside. It helps if it is just slightly larger than the day pack, so the fabric of the dry bag is not stretched. This means your day pack is going to get bashed around a bit, but that's what happens in rivers and canyons. More recently, people have been using silnylon 'dry bags inside their day-packs. The seams need to be well sealed, but the result is very light. You just have to be a little more careful to not pack sharp objects against the dry-bag wall.

Incidentally, when you open a dry bag in a canyon your hands will be dripping wet, and this water will get all over your precious dry stuff. Stick a bit of an old towel right at the top of everything inside the dry bag to dry your hands first. Very useful for when you want to get your camera out quickly.

Climbing and Alpine packs

These are getting very specialised. Don't buy one until you have had some experience and seen a few in real use. They differ fundamentally from a day pack or an overnight pack in that they try (correctly) to put the weight as low on your body as possible. This is great for real climbing, but the opposite of what you want for almost everything else. They are also usually a bit small for lengthy trips. Another disadvantage of a climbing pack follows from the shape: it is narrow at the top and wide at the base, making it very hard to get things into it or out of it.

Hostelling Packs

A very important difference you must watch out for is that between "real" bushwalking packs and hostelling or trekking packs. A hostelling pack is designed to be opened a bit like a suitcase; a bushwalking pack is more like a large bag. A hostelling pack often has a large zip right over the top: lay the pack down, unzip it right around, and behold: all your goodies spread out. Well, fine, on a hostel bed. Granted, your clothing may be packed more elegantly flat in a hostelling pack than stuffed into a bushwalking sack, but that's life.

The zip over the top is a disaster in the bush. It can rip, snag, open when it shouldn't, and let water pour in when it rains - even with the little protective baffles the manufacturers put over them. My experience with such zips on packs is not good. I once lost an expensive SLR lens out of a pack with an over-the-top zip, in thick scrub below Hat Hill Ck near Blue Gum Forest. The zipper slide caught on a bush and it opened up. Never again. (It is in an orange nylon bag, should you ever find it.) A bushwalking pack is a sack with a throat which can be done up, and has a lid which comes down over the top to protect everything underneath it. Of course, little pockets on the outside with little zips where the zip is fully shielded are usually OK, as long as they aren't very big and don't stick out at the sides.

Baby carriers

You can take small babies walking - with care. We have to consider what a baby needs to decide what is suitable: two main forms of baby carrier result: the sling and the papoose. The main distinction is whether the baby is old enough to hold his/her (it's?) head up without assistance. Below a certain age you have to support the baby's head, so the fabric sling carrier is probably the best. This also means the carrier (usually mum?) can keep a really close eye on bubs. Above that age the baby can sit up and look around, so a "papoose" carrier is suitable. Even so, baby is going to need some head support some of the time. They sleep quite nicely on your back.

The sling carrier is a diagonal sash with a pocket. The baby goes in it, between the sash and the carrier, so the sash holds the baby and its head up all the time. It looks a little "third world", but is extremely effective. Babies seem to be very happy in these: they are after all snuggled up next to Mum! They can be bought in baby shops (here I pass). Fortunately, babies don't stay this size for very long.

The papoose is a frame with a bucket seat, is carried like a pack, and the baby sits in it looking forward past your head. Rather than try to describe it in detail we suggest you look at one in a shop. Better still, find someone who has one in use. Things to look for are a reasonable range of size adjustment (babies grow fast), very good soft padding around the top rim, and some way keeping the pack upright when you put it on the ground. However, if the padding around the rim is not enough (it often isn't) you can always add some soft foam yourself. Baby will go to sleep leaning on that padding: make it soft. One word of caution: never ever give a child in a papoose anything sticky. The stickiness gets on their hands, and then they start to play with your hair ... There's more (there will be, when we get some contributions) on babies and baby packs in the Walking with Children FAQ.

Other Designs

Do not think you have to use an internal frame pack! There are many other sorts. As mentioned at the start, external frame packs used to be popular in Australia but these days they seem to be restricted to America. They are well known as being good for for long trips and large loads. And if they work well for those trips, they should work even better for short overnight trips. However, finding a suitable one here in Australia is a bit hard these days. This is getting technical, so you will need to look in some American catalogues to see what is available, or look in the DIY section for another idea. Alternately, go light-weight.

Some packs have no frame at all: they have a fixed harness. Most day packs are like this. It can be more difficult to get a good fit, but good fixed harness packs come in a range of sizes for that reason. They have the advantage that the harness is much smaller, lighter and cheaper. The sheer bulk of an adjustable harness can be a problem in itself, while a good fixed harness pack, properly padded down the back, can be much smoother. If you can go really ultra-lightweight, a "frameless" pack might be just the thing. Be careful though: part of the reason these ultra-lightweight frameless packs seem to work is really because the user is carrying so little weight. Load them up and it is a different story. There is an interesting article on making these at the GVP web site in America. However, it's fair to say that choosing a large fixed-harness pack for long trips requires a bit of experience.

You could go back to the swag: contributions from anyone who has tried it would be appreciated.

Pack Sizes for Children

This was contributed by Peter McGonigal .

"Some time ago, I raised the question of what is an appropriate load for a child in response to someone's inquiry about suitable backpacks. Since then, I have found the following materials:
http://aaos.org/wordhtml/aaos_rep/nov99/advance.htm
http://aaos.org/wordhtml/bulletin/dec99/acdnws8.htm
http://orthoinfo.aaos.org/fact/prev_...fm?Thread_ID=105&category=prevention;
http://aap.org/advocacy/releases/septschool.htm
http://www.aap.org/advocacy/backpack_safety.PDF

In substance, both the American Academy of Orthopaedic Surgeons and the American Academy of Pediatrics have expressed concern about the weight of the loaded backpacks school students have been using when carrying school books. It seems that most orthopods surveyed considered that the weight had become a clinical problem by the time that the weight had reached 20% of the student's body weight. The pediaticians suggested a load of not more than 10 to 20 percent of body weight.
However, there is a considerable difference between 10% [quoted elsewhere on aus.bushwalking] and 20%. So, it seems that some expert advice would be helpful. Are there any specialists on this group who would like to comment?"

Editorial comment: since I weigh about 64 kg, and my pack will usually weigh over 12 kg, I am normally carrying at least 20% of my body weight. In fact, I usually find that a load under 25% of my body weight, or 16 kg, seems to be far less noticeable than one just over that limit. I imagine that others might have their own thresholds of comfort. This seems a reasonable upper limit, for adults. But note that my bones are probably a quite a bit harder than those of young children, and my muscles and sinews are also much tougher. Especially for young children, a safety factor of two seems very desirable. That is, we should use a limit of around 12 - 15% of body weight. As children are smaller and lighter, this means their packs must be a lot lighter than ours. It does mean though that any one walking with small children is going to have to carry a lot more than their normal share! The joys of parenthood. RNC.

 

Pack Details

Single and double compartment packs

Some large packs come with one single compartment, while others have an opening (usuaully a horizontal zip) near the bottom and an internal divider. The latter are called two-compartment packs. The one-compartment pack is obviously going to be more waterproof when you throw it into a river, but it can present a problem with wet tents and parkas. Two-compartment packs solve that: you can put your wet tent and wet parka into the bottom compartment after packing the main compartment safely inside your tent. Any leaking water will just drain out the bottom harmlessly. This is a good idea, but does have drawbacks.

One big drawback we have found with two-compartment packs is that the upper compartment is much shorter. (This may not apply if you have a 90+ litre monster - it's too big anyhow.) The short upper compartment has to hold both your sleeping mat and your tent poles, and may not be deep enough. This means they stick up into the lid space. Maybe this won't harm the mat, but the tent poles are another matter. There is a serious risk of damage to the ends of the poles if they get caught on a branch you have just ducked under. Another problem is that the zip on the bottom compartment is going to leak. There may be a flap to block rain, but if you have to cross a river the bottom compartment can fill up. Finally, in bad weather when you are desperately fumbling around, zips can get jammed and damaged. So the idea of two compartments can be attractive, but it isn't perfect.

A one-compartment pack solves all these problems, but has a few of its own. If all you have is a single compartment pack, where do you put a wet tent in the rain? Under the lid is the obvious answer. After all, you have to access under the lid to put the poles away anyhow - you wouldn't leave them tied on the outside, would you?! The key thing in this case is to make sure any water leaking from the wet tent is diverted outside the pack. This is possible if you put the tent on top of the throat material rather then inside it, and hold it in place with the top inner strap. If the throat isn't waterproof (it should be!), take a little bit of plastic or proofed nylon to put on top of the throat, under the tent, or make yourself a waterproof tent bag. I do both, and I use the square of waterproof fabric as a tablecloth for meals as well.

There is no perfect pack. However, the two compartment Macpac Cascade has often been cited as a classic reference design for an internal frame pack, even if it is rather heavy. The author had one for many years, and hammered it. The one-compartment Macpac Torre is almost the same, and my wife finds it fits her very well, even if it heavy. But the author now prefers his ultra-lightweight external-frame designs: they are more comfortable.

Bag Shape, pockets and things tied on

The design of the bag itself is important, and includes such things as the overall shape, pockets on the outside, and attachment points on the outside.

The shape of the bag may not be something which you immediately think about. However, consider three possibilities: a parallel shape, tapered to a narrow top, and tapered to a narrow bottom. A parallel shape is simple to make and there is nothing wrong with that. A shape which is wide at the bottom and narrow at the top is good at putting the load down low, and that is good for an alpine or climbing pack, when you don't want too much load on your arms. Packing this design is a little more tricky as there is this huge cavity down the bottom which is hard to get to. The downside to this design is that it is the opposite of what you want for bushwalking, as discussed above. Sadly, most current internal frame packs are this way.

Then you have the very few packs which open upwards, placing the load a bit higher on your back. It helps if they are shallow in the front-to-back direction: that keeps the load close to your back and reduces the strain. Sadly, there are few of these designs around and most people do not realise how much better they are. The Aarn packs from New Zealand are a good example of this approach, although I found the Aarn pack I tested to be a bit narrow over all and too tall for my 1.70 m (5' 7") height.

Some vendors advertise the number of external pockets their designs have. This is misguided marketing, aimed at the tourist/hosteller crowd. The reality is that you don't really need external pockets: you can fit everything inside (or should be able to!). Large external side pockets get caught on our scrub so Australian manufacturers don't fit them. Imported packs often have such pockets and are usually avoided by Australian walkers. Many imported American packs have mesh pockets on the sides and back of the bag: these do not last very long in our bush, and the contents get lost too easily. One or two small outside specialised pockets might be useful (although they often leak); an external map pocket certainly is, but few offer that. A pocket on the top flap is popular, but this usually leaks and exposes things in it to real risk of damage when you duck under branches. Why do people put spectacles and so in in the top pocket? The claim is that external pockets allow you rapid access to things you might need - but how often do you need things that quickly? We have had equal success with a 'day bag' placed just under the top flap: stuff in there is just as accessible and is a bit more protected.

The same applies to "things" tied on the outside of the pack. The picture here shows an extreme example. (Actually, the ladder was being carried in to the MUMC Feathertop Hut during its construction: hardly a fair criticism!) You may see people with foam mats rolled up and tied on the outside: these mats get shredded as they go through the bush and the track gets littered with little bits of coloured foam. This is a sure sign of a novice and we strongly object to these bits of litter. You also see sleeping bags tied on the outside. Usually the stuff sack is not waterproof, and whatever is holding it onto the pack is inadequate. I have collected at least one pack off the track this way. (Words fail me here, but I bet the previous owner was cold that night.)

If you must tie anything onto the outside of your pack, make sure it is well covered against damage, and can't fall off. Better still, put it inside. If there isn't room, ask yourself if you are carrying too much gear. About the only thing the author would ever carry on the outside of his pack would be a fuel bottle in an external pocket (the leaks stay outside!) or an ice axe. Oh yes: skis and poles get carried on the sides of a pack sometimes, as close as possible to your back.

Pack materials

A great debate can be had over the bag material. Once all packs were made of 12 oz proofed cotton canvas: when this got a bit damp the fibres swelled up and blocked the pores, making the bag "waterproof" (in theory). What actually happened was the canvas did block most of the water, but the inside surface was wet nonetheless, and so was some of your gear. Then stronger synthetics such as Cordura™ were introduced, but the PVC proofing on them was initially very poor and rubbed off after a (short) while. Once this happened the bag leaked like a sieve, and everyone swore off synthetics.

The cotton canvas has got better: it is now made of a polyester/cotton mix which is very tough. But it still does get a bit wet (and heavier) in the rain, and is not as abrasion-resistant as the synthetics. For this reason some packs are still made of poly-cotton canvas but reinforced with Cordura around the base. However, do not reject a synthetic pack these days: the proofing on the synthetics is much better today, the packs are often lighter, stronger and they can be very functional. But the stitching holes do seem to leak more easily on some loose-weave synthetics (see also Canyon packs). It would be nice if the manufacturers used a decent seam construction on the pack bag, but a second line of stitching seems to be too expensive for them to bother.

Shoulder Straps and pads

The shoulder straps on internal frame traditionally have some padding, but I wouldn't worry about getting thick padding. It doesn't work and adds weight. I have actually used 50 mm nylon seat belt webbing without any padding for a while: it was OK, sort of. If you can limit the weight of your pack then webbing is just fine by itself. Some shoulder straps are shaped to make S-bends over your shoulder, but the laws of physics don't allow this to be very effective. Forces go in straight lines, and a fairly simple design is best. Far more important for comfort is the weight in your pack(!), the correct adjustment of the balance straps, and what clothing you are wearing. If you have a bad fold or crease in a heavy shirt right over your collar bone under the shoulder strap, you are going to get very conscious of it after a while.

But I will concede that a little padding can be useful. Sometimes I use pads of EVA 40 foam about 10 mm thick and 60 mm x 150 mm in size. They have the distinct advantage that they help prevent the shoulkder strap from rolling up. That, rolling up, is the last thing you want!

Strap Buckles and Slipping

In search of a single design with the widest possible market appeal most pack makers use adjustable buckles on the straps, including the shoulder straps and the top straps (balance straps, load lifters, whatever). This is in principle a good idea. However, the designers of the buckles also want them to be easily adjusted, even while under load, and this introduces a problem. The design of the buckle is compromised to get the ease of adjustment, which means it does not lock on the webbing so well. This is exacerbated by random changes in the design of the webbing itself by the webbing makers, or possibly by attempts by some (not all) manufacturers to buy the cheapest webbing and buckles they can find. The end result is that some webbing on some buckles on some packs slips very slowly through, and what was once correctly adjusted ceases to be so after a few hours. Slowly, the shoulder straps and the top or balance straps get longer, and the load starts to drag. It can take a while before you realise what has happened. You may have to re-adjust some buckles at times to keep the pack snug against your back. The improvement in comfort can be surprising. You can also modify the buckles on your pack if you find they are forever slipping: instructions are given here.

On a more serious note: some pack makers use cheaper ('generic') buckles made in Asia, rather than top brands such as Fastex and Duraflex. The cheap Asian brands can snap under load. I was ski-touring when the waist buckle snapped on one of my packs. OK, it was given a shock load when I fell over on the ice, but not having a waist strap did make life a little more difficult! Good brands matter here. Unfortunately, it can be difficult to tell whether the buckles on a pack you are thinking of buying re good or not. You could try asking the staff. Of course, if you are buying in a discount shop, you can almost guarantee that the whole pack will be made in Asia.

Waist Band or Hip Belt

These days most packs have a "waist band" or hip belt. This is a broad belt around your waist which pulls the pack onto your hips (or bum) and transfers some of the weight off your shoulders onto your hips. The idea of the load transfer seems to be a good idea for internal frame packs since they have poor load distribution anyhow. It has to be matched with a good bit of padding at the small of the back over your bum: this is a key design area to check for comfort. If it is too thin, too small or in the wrong place it won't be comfortable. Some women seem to have more trouble with this than men, for reasons which could not possibly be associated with the shape of their anatomy J . For this reason some pack makers have a 'woman's model' or can swap the standard male waist band for a female version. For a girl this is worth checking. The same applies for shoulder straps: female versions are sometimes available to accommodate that slight but delightful difference in chest shape.

However, life is never quite that simple. Some people have a lot of trouble finding a hip belt which works for them. The reason is that a hip belt only works if your hips can support the belt. If you have slim hips, or a narrow pelvis, you may find that even a tight hip belt can slide down your hips, past your backside. There is just not enough sticking out for the belt to sit on. I have this problem myself. In this case you can't rely on the hip belt support much of the pack weight. You may need to move to an H-frame pack, if you can find one.

Even with small day packs and H-frame packs which do not need the load transfer to the hips, a belt around your waist is a good idea. The benefit a waist belt brings is more stability of the pack on your back: it stops the bottom of the pack from moving sideways when you are bouncing around. However, such a waist belt can be far lighter than the reinforced girdles you see on some internal frame packs.

Haulage Loop

Many packs have a webbing or haulage loop at the top between the shoulder straps. This can be very useful in two ways, as long as the loop really is secure. The first use is as an anchor point should you have to do any pack hauling. The second use is as an aid for picking up and donning a heavy pack. Strangely enough, it is usually better to pick up a heavy pack by this loop than by one of the shoulder straps. The reason is that swinging a pack around off the shoulder strap can damage the harness mechanism - although once the pack is on your back it is quite safe. You pick the pack up by the loop doing a one arm press to the shoulder and then thrust your elbow through the shoulder strap as it goes over your shoulder. On second thoughts this action is better demonstrated than described. The strength of this loop is actually an extremely important factor in design: the stitching holding the loop and the shoulder straps to the bag is crucial. Some cheap packs are reported to have failed here.

Top Compression Strap

A little pack will keep it's shape well enough, but a large pack tends to bulge a bit at the top. For this reason good large packs have one or two top compression straps. These go from the top bar, over the throat material, to the material at the front, When your pack is full (or before!) you do the top drawcord up, do the throat up (to keep the water out), then you do up this compression strap to hold the top of the pack in. It prevents the bag from leaning backwards too much. It is also useful for holding a few large objects in place, like a wet tent and a parka.

Pack Covers

Even if your pack is completely waterproof it will probably absorb a fair bit of water on the surface under heavy rain. More often a little will creep in at some of the stitching or zips. For very little extra weight you can stop this: a light pack cover is all that is needed. This consists of a bit of light waterproof nylon cloth shaped to cover the top, sides and back of your pack. A draw-cord around the edge holds it on and makes your pack look a bit like an astronaut backpack. Tying the end of the draw-cord to the pack is a very smart move: I lost a bright orange pack cover on the top of Mt Carruthers once in a storm - it sailed off like a parachute, headed for the Barry Way.

You can buy pack covers at bushwalking shops for not too much money. They come in a variety of weights - often rather heavy. Or you can make your own, and tailor it to fit your pack better than the heavy all-purpose units sold. From experience, I don't think the heavy ones are worth the extra weight - our very light ones have lasted many years of rough treatment. After all, the pack cover is following you. It's your clothing which gets the most wear from the scrub. Even cheap light not-very-waterproof acrylic-coated nylon is going to deflect most of the rain. Even if a little bit does get through the cover, very little will then get into your pack.

Revert for a moment to the picture near the top of the page, of the guy in the snow with his pack dragging backwards. He has a pack cover on his pack, but he still has problems. The pack is leaning backwards: the snow is going to land in the gap between his pack and his back. It is going to melt there, and what doesn't leak into his pack through the vast amounts of stitching there is going to soak into his clothing. This can still happen to some degree even if your pack is riding properly, and we have seen this happen. However, the poncho idea mentioned elsewhere can serve three purposes here: it can cover your pack, it can cover you, and it can also cover that gap between you and your pack. It can be very effective.

Pack Liners

Packs can leak, especially two-compartment ones, and especially when thrown in a river. Sometimes you have to swim across a river with your pack; sometimes you even have to do this many times. It would be nice to keep the contents of your pack dry. You can package everything in small nylon bags lined with plastic bags (freezer bags are readily available), and this is highly recommended anyhow. It is especially recommended for dry food, sleeping bags and spare clothing! But we sometimes line our packs with some sort of waterproof bag as well. This can be a simple as one or two green garbage bags. These are a bit fragile, but may be suitable (with care) for a single river swim. A heavy plastic bag is good, but finding these is difficult and they may be a bit too heavy at times. Easily available bags (like in supermarkets) are as follows:

Some people make a waterproof liner bag to fit their pack from genuinely waterproof nylon or polyester material, taking care to seal the seams properly. Such a bag may be weaker than a "canyon dry bag", but it will also be a lot lighter. The DIY section covers such materials: silnylon (properly sealed) has been used very successfully, and 'weldable PVC-coated nylon' has also been used. But caution: a lot of what is sold as 'waterproof nylon' in the local shops is not: it's coated with acrylic and barely showerproof. Shower curtain material may not even be proofed.

© Roger Caffin 1/May/2002, 17/Oct/2007