Lightweight Internal Frame Packs: a State of the Market Report – Part 1C: Main Bag & Comfort

Hi John

> I'm still not convinced that external frame packs aren't superior in concept
Ahem. The packs I make do have an external frame … :-)

> I'm still waiting for the ultimate article on pot circumference
It's coming!
Yes, a lot of the metrology has been done (you can thank Tony Beasley for that), and the results are quite interesting. Some anticipated, some not. Stay tuned. No pre-releases though.

Cheers

Yeah Roger I noticed . Your remark about your build and fit made sense or at least threw off the partisans. For me it was just history and luck I ended up with an expedition frame that is freestanding and very light. I've since bought other even lighter frames built of PVC that look promising . Better ventilation too. The jury is still out. I have a Mountainsmith ghost and will try my Daughter's Golite Odyssey soon as our torso's are the same. To mangle Melville, " Your gear is on i'ts passage out and not a voyage complete"

> I'm still waiting for the ultimate article on pot circumference
It's coming!
Yes, a lot of the metrology has been done (you can thank Tony Beasley for that), and the results are quite interesting. Some anticipated, some not. Stay tuned. No pre-releases though.

Its coming, as of this week I am taking a days leave per week to get the article finished.

A lot of people on this forum do not realize how much time and effort can go into some of these articles, my last two articles made me 20c/hour and that does not take into account the costs involved, the pot article is going to be similar. I am sure many other authors of BPL article have similar experiences, it is my hobby.

To the people doing the criticizing, if do not like they way Roger has presented his pack review you are welcome to do one yourselves.

Tony

As far as I'm concerned the installment about pots circumference is a bigger deal than the next Stephen Spielberg, and I wish it had that budget. Ive placed my bets with a wide REI set with bottom ribs to keep the sliding down. it's the windscreen coverage and airgap I'm waiting to adjust. And I agree . Don't ask your walkers to take a hike unless you are going to go to bat. I think turnabout would be fair or foul play. A review of Aussie and Britpacks by some Southern Caliphs and Gramweenies?

Travis I still must disagree.

If you look closely at your definition you see that it begins "any theory." As I tried to make clear in my last post I was not basing my comments on "theory" so my statement could not be absolutist as it is not based on "any theory" but rather upon my direct observation.
(Roger's claim as worded is strictly theoretical).

You are confusing "tone" with with the "burden of proof." You are welcome to tell me to tone down but it is no defense of the original question as you would have it.

One of my criticism of the initial language of the piece was that Roger made an unsupported claim. Still after all this, this matter has not been addressed. Rather I am called an "absolutist" for discussing actual experience that contrasts and refutes Roger's theoretical claim. See where I am going with this? You are committing a logical fallacy. Just becuase you don't like my tone that doesn't make my question any less valid.

See why I bring up radical transparency? I am trying to get Roger to account for his claim. Insofar he has not responded to this simple request for his evidence behind his contention, that, "bladders will burst when packed inside a pack."

OK so I myself made a mistake for echoing the tone that was used in the original article. I'm sorry if I offended you.

Now may we actually get the evidence behind Roger's claim that a bladder with burst when it is packed inside of a rucksack? All this mess goes away if one simple request is fulfilled.

Roger made a claim, we want proof, simple. I think the tone you hate so much Travis grows and grows as the orginal question gets brushed under the rug and everyone circles their wagons. This entire diologue wouldn't have ever gone this far if Roger had done one of two things.

1) Admited me might have made a mistake and that he has no proof of his claim. There are enough members here who DO use them. Either way, the members here would not hold it against him for admitting he made a mistake. Hey none of us are perfect, we understand.

2) He provided evidence of his claim that it really is stupid to put a bladder in your pack. I.e. he tells us how on one or several trips though the brush he and his hiking partner both burst their hydration bladders' while they rode shotgun inside the pack.

Thats it. That's all I've been asking for this entire time. 1) or 2) that it. Writer's responsibility, Accountability. Whatever you want to call it. That what the Internet is all about. If you say in publicly in the square own up to your claims. Travis, I am sorry if you feel I am the one that is out of line. Perhaps we have different concepts of personal accountability, I don't know. But if you said it, you own it, you account for it. Call me out of line all you like, but that doesn't free the original writer from the burden of proof.

In the world of running, if a runner gets dehydrated to the point of 2.5% of body weight, that is considered a big warning. If 5%, then that is a huge warning not to continue until it can be overcome.

–B.G.–

Hi Charles

I think we might have to agree to disagree.

For the record, I did not say that a bladder WILL burst when packed inside a rucksack. I said that a bladder inside MY pack stuffed full of MY gear might burst:

'When I fill my pack with gear the pack is generally fairly tightly done up, to keep all the gear secure and stop the pack from flopping around. The idea of having a flexible bladder of water stuffed down inside the back of the pack being crushed by the rest of my gear seems to me to be the height of stupidity: there is every chance of it bursting under some minor extra impact.'

Yes, I do know of one case where that happened. That was some time ago and I do not remember the details. I have also had other containers inside my pack damaged by hard objects (pitons, I think). But if a bladder works for you, go for it.

Cheers

"Another thing that the mass of Americans here should remember before going fully off the handle about his review is that Roger is from a Commonwealth nation. I'm unsure if this is universal but over the years I have noticed that there is a certian style used to express opinions for Commonwealth members that Americans find abrupt, condescending, and arbitrary"

May I point out that here are also differences in personality amongst people from Commonwealth countries? Some may be abrupt and others may be almost like Uriah Heep.

Well, since we're talking about reviews – and cultural differences – and this is a comment I've made here before – a lot of the user reviews on this site read like the author is submitting reviews for Outside (which I've subscribed to for about 20 years). It seems like no-one wants to give any item less than 5 out of 5. The classic case in point was the review of a Patagonia Houdini which gave it a 5/5 but went on to note that it wasn't particularly breathable: since breathability is the key point of a windshirt (anything can be windproof – windproof and breathable is the issue) wouldn't that automatically mean that it wasn't a 5? The result of this is that I don't check reviews on this website because rather than being warts and all there's barely a wart in view – but in contrast, if you check the reviews on Outdoorsmagic they can be hilariously biting – and far, far more open about a product's failings. And if I'm going to spend a large chunk of my declining salary on gear then I don't want to buy a lemon on the basis of some puff piece that's been copied from the manufacturer's sales copy.

Re the bottom of packs: I think that angled bottoms are a sign of good design – Macpacs always had them – disagree with Roger on that and I also like big mesh side pockets but prefer solid zipped ones on the back. But they do need to have a "3D" design to be useful when the main pack is full.

"They're universally so polite and considerate that I want to strangle them."

Us Australians are like that too.

But it has to be said that the Canadians aren't really members of the Commonwealth – they don't play cricket.

Charles,
No, nobody has offended me here, including you. No feelings have really been hurt. One of the major shortcomings of indirect contact (internet) is the complete lack of personal delivery. It's amazing how the way a person actually says something can differ completely from how words on a page make it seem like it comes across.

I do appreciate your staunch defense of your position, and I shall stick to mine. However, I also believe much of the debate is simply due to the communicative restrictiveness of faceless technology.

Rhetoric can really get in the way of progress, be it intentional or not, on either side of the fence. History has yet to teach that to politicians.

How did George Gershwin put it? "You say potato, I say potatho. Let's call the whole thing off."

By the way, you have to admit that Roger is probably having quite the time watching the back and forth banter in this thread. I can imagine him, much like my fiancee sits down and reads the comics every morning, sitting down to a cup of coffee reading our interplay and having a good laugh at our expense!

No matter. I do the same thing when I read the news every morning and the Democrats and Republicans sound like a bunch of uneducated, whiny, spoiled, brats yelling back and forth at each other.

It`s too cold to wack a weird ball with a funny looking paddle…

And personally I hate bladders. I have had them pop in may pack. weight Isn`t a factor in that its whats pushing against it. Opinionated Views are very informative I find. Working in the industry, all they do is sell staff on what features they add. Most of the sales reps spend the whole time talking about features but pack fitting maybe 10 min. I had a Mountain Hardwear PK wear we were never told how to fit a pack. Pretty awesome for new staff, `heres what the pack has` fitting it doesn`t mean much…

I didn't even realize this was a "flame-war" until someone said it was. I thought it was just opinionated discussion and I was enjoying every bit of it. I found the various differences to be enlightening and cause for much self reflection on my own gear choices and how I've been doing things. Have I changed anything because of it? Not yet, however, I have had my eyes opened to what works for others in other parts of the world. These differences I will keep in mind as I outfit myself and pack on future trips.

I was in no way offended by the article. In fact I enjoyed it better than the lame-o wishy washy style of writing that tries not to offend anyone. I hope Roger continues to post informative and opinionated pieces as they provide insight as to not just how something worked for the author but also a glimpse at why it worked.

hi roger

lol, yes 15kg of body water loss doesn't sound healthy
I corrected typo

Hi John,

>As far as I'm concerned the installment about pots circumference is a bigger deal than the next Stephen Spielberg, and I wish it had that budget. Ive placed my bets with a wide REI set with bottom ribs to keep the sliding down

I wish I had the Spielberg budget too, if you want to send me one of these ribbed bottom REI pots I would be happy to include it in the pots size tests.

>it's the windscreen coverage and airgap I'm waiting to adjust.

maybe sometime soon ???

> A review of Aussie and Britpacks by some Southern Caliphs and Gramweenies?

I would too but good luck finding any Aussie designed pack that is lightweight by BPL standards.

Tony

>> prevent excessive dehydration (>2% BW loss from water deficit)
>By way of reference, for everyone else to consider: I weigh ~64 kg. 2% of that is 1.28 kg or 1.28 L of water. There is absolutely NO WAY that I can drink that much water in the space of 2.5 hours of walking. Can you? Should you? (The answer to the last is No: you can kill yourself that way.)

Not true. Hike in high desert? That's exactly how much water was right for me when at ~13000 ft in the Eastern Sierra. Similar body weight. It was 85F (30C) outside.

As mentioned earlier : individuals are different. Environments are different. Maybe someone drank too much vodka the previous night? Maybe something else…

Drink enough to stay hydrated.

While it is indeed possible to kill yourself by drinking too much, data suggests that most of the time the fluid volume is not the culprit, but rather a lack of electrolyte consumption.*

The aforementioned ACSM position stand measures fluid loss rates for various sports. Assuming that backpacking is more like tennis and running than any of the other examples used, at least when going uphill, we can assume that sweat rates of 1-2 liters an hour are quite common while hiking. Add to this the work of Rehrer et al**, which while noting the substantial variability between individuals still seems to suggest that the rate at which fluids can be absorbed via the stomach and small intestine is usually a good bit below 1 liter an hour.

These articles seem to suggest (individual variations make it difficult to say so with statistical significance) that gradual and sustained fluid intake promotes gastric emptying: ie you will hydrate better and be less like to bloat and become hyponatremic if fluid consumption is not intensely episodic.

*Consensus Statement of the 1st International Exercise-Associated Hyponatremia, Consensus Development Conference, Cape Town, South Africa 2005. Clinical Journal of Sport Medicine. 15(4):208-213, July 2005.

**Rehrer et al. Exercise and Training Effects on Gastric Emptying of Carbohydrat Beverages. Medicine and Science in Sports and Exercise 21:5.

I offer a specific experience of exactly how a hydration bladder can fail in a pack. My husband wanted a neatsy cool Camelbak bladder for his pack for our Wonderland Trail hike. So I got him one and he installed it in his Atmos 65 pack. And he packed it all pretty tightly, all the way up to the top. (Yes he brings more clothes and gear than I do but does not learn well from me lecturing…) For a few days all was well. Then the leaking began. What happened? The Camelbak (I won't speak for other brands but some others are similar designs) has a wide round fill-opening at the top, with a rigid collar that makes filling and cleaning easier. When he packed the pack tightly to the top with the bladder only partially full (because, say, he was rummaging in the pack for something and did not have occasion at that point to top off the partially-drained bladder), the collar, with stuff pressed against it from above, acted as a "cookie cutter" against the opposite soft plastic surface, and eventually it cut through. No effect until after the next time the bladder was refilled and the pack repacked to the top. Then he got this mysterious seeping of water onto the contents of his pack.

He threw the neatsy cool Camelbak into a trash can at the next road intersection, and accepted one of my two 1L Aquafina bottles for the rest of the hike.

All this talk of how a bladder can fail *inside* a pack, and I totally forgot of how they can fail *outside* the pack!

My finacee had her Platypus laying out next to her pack after we had set up camp. We went off to play in the lake, and came back to a chewed bladder. Some deer had its way with it and put a few small holes right near the seams. That was on day 1 of 6. Luckily, I was able to repair it with seam grip and superglue, but the rest of the trip we were really worried about it leaking again.

If a person chooses to use a hydration bladder inside their pack there shouldn't really be ANY major concern for it excessively leaking or bursting onto the contents inside the pack assuming that person has used safe practice and placed all moisture sensitive items inside a waterproof/resistant barrier such as a cuben sac, pack liner, trashbag, drysac, etc. If in the event the bladder does happen to malfunction by user error, product defect, or what have you, the only thing getting doused in water is the main pack body and bottom and perhaps a few less vital items. It's easy to blame a hydration pack for wet gear and write it off as a silly method, however, if gear shouldn't be getting wet in the first place then it should be protected accordingly. Bottles are excellent and work for some, others don't like the fiddle factor on the trail using a bottle and prefer the simplicity of use while hiking found in a bladder. Both methods have a certain set of precautionary measures, and simple techniques that when followed should put no gear at risk. In the end, sufficient practice and application of both hydration methods should find the person proficient at acquiring water, storing, and hydrating along the way. I prefer bottles and would likely find using a hydration bladder fussy and cumbersome, mostly due to my lack of experience with it and nothing else.

PLEASE don't lump us Kiwis in the same category of manners as those rude Australians!!!

;)

Though we are, of course, as opinionated as anyone else on the planet.

And come to think of it, many Indians (as in the subcontinent) are very polite, at least to your face. I've met a lot of really polite British people too. And many others. To be fair, Roger is always polite. He can tell you your choices are stupid or silly, and then say *cheers* :)

I like bladders, end of story. They solved an ongoing problem for me in terms of migraines, which can be triggered by very subtle states of dehydration. However, I do recognise, peer-reviewed research aside, that heat and drought adapted humans can go a long time without drinking. Just think of the Kalahari bush-people…everyone is different.

>> prevent excessive dehydration (>2% BW loss from water deficit)
> By way of reference, for everyone else to consider: I weigh ~64 kg. 2% of that is 1.28 kg or 1.28 L of water.
> There is absolutely NO WAY that I can drink that much water in the space of 2.5 hours of walking.
> Can you? Should you? (The answer to the last is No: you can kill yourself that way.)

Roger,

Different folks have different needs. Perhaps what you say is true for you.

In my case, however, when doing a strenuous workout at the gym or when hiking vigorously in warm weather, I can easily drink 1L/hr of electrolyte drink (which includes about 6% carbohydrates).

A more common rate for summer hikes would be 1L per 2 hrs — still a rate that you say would kill me. Since I am here and posting this, I guess it did not kill me :)

— MV

I just came across this bit of research, and it made me think of this *discussion*:

"We Only Trust Experts If They Agree With Us

We only consider scientists to be experts when their argument is in line with our own previously held beliefs.

We think we trust experts. But a new study finds that what really influences our opinions, more than listening to any expert, is our own beliefs.

Researchers told study subjects about a scientific expert who accepted climate change as real. Subjects who thought that commerce can be environmentally damaging were ready to accept the scientist as an expert. But those who came into the study believing that economic activity could not hurt the environment were 70 percent less likely to accept that the scientist really was an expert.

Then the researchers flipped the situation. They told different subjects that the same hypothetical scientist, with the same accreditation, was skeptical of climate change. Now those who thought that economic activity cannot harm the environment accepted the expert, and the other group was 50 percent less likely to believe in his expertise. The study was published in the Journal of Risk Research.

The investigators found similar results for various other issues, from nuclear waste disposal to gun control. Said one of the authors, “People tend to keep a biased score of what experts believe, counting a scientist as an 'expert' only when that scientist agrees with the position they find culturally congenial."

If you own an MSR Dromedary bag, here's a neat trick:

Fill it mostly full, put on the lid. Take it into the yard, put it on the ground, and leap upwards, landing on the bladder with both feet and your full weight. The lid will fly off, water will go everywhere, and the Dromedary will be unharmed.

I'd never use a mere Camelbak type bladder on a trip where loosing my water would be problematic.

I Use this bladder:

http://www.kathmandu.co.nz/Accessories/Active/60484/Hydration_Bladder_-_Widepac.html

And it appears to be as close to indestructible as any I've found.

David,
While that sounds like a neat trick, I don't think I'm going to try that! :)

I used the Dromlite 4L during a desert trip. I was glad to have the capacity and durabliliy.