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Paul McLaughlin
(paul) - MLife
Re: re: frameless packs on 12/05/2012 13:31:41 MST Print View

Dave C wrote: "While having shoulder straps which attach substantially above torso length is indeed required to both not have load lifters and guarantee no weight on the shoulders no matter the load, I don't think most will find this desirable. Indeed with a frameless or lightly framed pack the lack of dynamic mobility such a design creates negates the primary virtue of such packs".

I fully agree, and that was partly my point - perhaps not clearly expressed. To elaborate, my thinking is that lifters don't work well on frameless packs (since such packs lack the structure that the lifters require for proper function)and are thus a waste on such; that they are of doubtful utility on semi-framed packs (foam pads and the flimsier varieties of framesheets) and very useful on packs with either stiff enough framesheets or stays (or combinations thereof). But if the pack has stays or a stiff enough framesheet, I doubt very much that it can be as comfortable and as secure (moving with you as you move) without lifters as with, regardless of how well if fits. Having made packs with all the variations - no frame at all, foam pads, plastic framesheets, stays, and with and without lifter straps, I have settled firmly on lightweight stays and skip the framesheets/pads. 3 oz. worth of aluminum gives me weight transfer far better than any foam pad ever will, plus effective lifter strap attachment points.

Of course, when you get light enough you don't need to put any weight on the hips and then you don't need a frame, and the game completely changes. Where that point is varies a great deal individually, which is a big reason why so much debate goes on around frameless packs - some folks are comfortable with 40 lbs on their shoulders, others don't want more than 10. You have to find that out for yourself.

Eric Blumensaadt
(Danepacker) - MLife

Locale: Mojave Desert
"Frameless" on 12/05/2012 18:54:02 MST Print View

Thanks for a very objective review of these two packs.

As a confirmed internal frame user I STILL contend there is a way to make a "frameless" pack, as I have posted here a few times.

To wit:

1.> Using a CFC pad like the Thermarest Ridgeline. cut it in half laterally, which should put the cut just below or at the hips, depending on your height.

2.> Use wide Heavty Duty Velcro and Gorilla Glue to attatch mating pieces to the cut mat ends for reassembly. Gorilla tape Velcro ends so they don't pull loose on disassembly.

3.> Roll each half tightly and measure the diameter of the roll. Them make 2 fabric tubes in the inside of the pack bag against the back to recieve these rolled mats.

4.> Insert rolled mat halves and use cloth and Velcro top covers to hold them down.

Now you have an internal "frame" that will give good support and padding and permit lift straps to work properly.

Edited by Danepacker on 12/06/2012 13:37:54 MST.

HElinTexas C
(Helintexas) - MLife
Interesting article on 12/05/2012 19:29:30 MST Print View

I bought the GoLite Jam a couple of years ago. I used it on a couple of trips. No matter how I packed it. I hated it. It made my loads feel heavier. I also tended to walk leaning forward ever so slightly.

I happened to take it with me when trekking in Tanzania last year. My guide had a god awful ragged out backpack...basically a kids pack that had been thru the wringer. He had picked my pack up to carry it and he loved the GoLite. It worked perfectly for him. (I ended up giving to him as an extra tip.). It is one of those things where different body types need different packs.

I went to the heavier ULA circuit and I love it. It fits me perfect and I can wear it with a heavier load (than the one I had on my last trip with the Jam) and hardly notice it. I LOVE the weight transfer to the hips. I like the way the shoulder straps fit me. I love the wide waist belt. I love placement of the side pockets. Heavier feel lighter to me.

jeffrey armbruster
(book) - M

Locale: Northern California
How packs work on 12/05/2012 19:54:37 MST Print View

Excellent article. Thanks for your work.

And now let me agree with Roger. 100%. With the caveat that everyone has a different anatomy, etc.

Look, the old adage was 'weight on the frame, frame on the hips, load carried by the legs, which are by far the most powerful muscles in the body.'

I've never been able to find a frameless pack--or even a somewhat frameless pack--that could successfully transfer load off of my shoulders/spine/back and onto my hips. Throw in a bear canister and this becomes doubly true.

I'm curious: if someone were to produce an external frame pack that weighed two pounds or less, would members of this forum consider it? Oh wait, even more: how many members of this forum have even used an external frame pack?

(My external frame pack, which I love, weighs 2 1/2 pounds. I top out at 25 lbs. for six days, including the pack.)

Mary D
(hikinggranny) - MLife

Locale: Gateway to Columbia River Gorge
How Packs Work on 12/05/2012 20:13:51 MST Print View

I used an external frame pack for many years and hated it. It would zig when I zagged and pull me off balance. I guess I always thought that's what packs do!

I now have a lightweight internal frame pack which (when I bought it, before I trimmed unneeded straps) weighed 29 ounces. It will easily support a 35 lb. load, more than my knees and feet can carry. It transfers practically all the weight to my hips, important for me because my shoulders are very pressure sensitive. It has removable aluminum stays so can be used as a frameless pack if I want (I seldom do). Most important, it moves with me so I don't get off balance!

The point above, that load lifters really don't work without stays, definitely is true for my pack!

Stephen Barber
(grampa) - MLife

Locale: SoCal
re: frame pack on 12/05/2012 20:19:00 MST Print View

" if someone were to produce an external frame pack that weighed two pounds or less, would members of this forum consider it? Oh wait, even more: how many members of this forum have even used an external frame pack?"

Absolutely! My wonky back insists that I keep weight off my shoulders and on my hips. My UIA packs do a great job of that, and frameless packs, even at "light" pack weights of 15-20 lbs are a nightmare for me. An external frame pack at 2 lbs would definitely be worth a try.

And yes, I've carried External frame packs for years! My favorite was a Trailwise (? - the Colin Fletcher liked), but it was stolen decades ago, and I was unable to get another. Having started with canvas rucksacks, I still remember my joy and amazement at trying on an old Kelty with a HIP BELT! That was a wonderful experience! :)

Tom Kirchner
(ouzel) - MLife

Locale: Pacific Northwest/Sierra
Re: Re: How Packs Work on 12/05/2012 20:41:37 MST Print View

"It does not have to rely on load transfer to the hips either, which is fortunate as I don't have much in the way of hips to support it."

Hi Roger,

I'm a bit confused. Does this mean you are carrying the entire load on your shoulders? Up to 45 pounds? If so, you can add the honorific "gnarly" to your curmudgeonly persona. ;0)

"I just don't find the fad of frameless packs to be convincing...."

+1 The benefits of a stay system of some kind, either internal or external, seem pretty obvious to me, but then I guess I'm sort of feminine in that I don't tolerate weight on my shoulders very well.

Cheers

Dan Durston
(dandydan)

Locale: Cascadia
External on 12/06/2012 05:50:57 MST Print View

" ..if someone were to produce an external frame pack that weighed two pounds or less, would members of this forum consider it?"

ULA Ohm? Great pack. Popular yet still underrated. Carries so much nicer than a HMG Windrider which gets all the press these days.

Ken Thompson
(kthompson) - MLife

Locale: Behind the Redwood Curtain
Re: External on 12/06/2012 06:15:50 MST Print View

Ohm has the frame inside now.

James Marco
(jamesdmarco) - MLife

Locale: Finger Lakes
Pack collapse and load lifters on 12/06/2012 06:47:41 MST Print View

Load Lifters and some sort of support frame are needed with most packs. For pack loads of less than 10 pounds, you can probably skip them, since the pack itself, when compressed supplies enough support. Load lifters are not needed unless the loading exceeds the height of a frame used to support it.
Pack Collapse
The stiffness of the frames makes a huge difference in the performance of a pack. For anything up to about 25#, a fan folded pad works well as an internal frame. For loads up to about 35 pounds, a stiffer frame is wanted. Plastic or metal frame sheets, stays, etc can all be used depending on the load to be supported. For heavier loads an external frame is likely wanted.

Most lightweight, UL hikers or through hikers rarely reach 35 pounds. The exception is during desert hiking where large amounts of water are needed. Each gallon(US) weighs about 8-1/4 pounds or so. It is relatively easy to have a low base weight, fuel and food of about 20 pounds and still carry a 45pound pack. An external frame makes sense for these conditions. More normally, water is not a big weight, though. I typically hike through woodlands carrying about 1liter of drinking water. All else is made up as I go at breakfast and supper. I think this is a little low for many, but even two liters would be plenty for most hikers on a day’s hike...about 5 pounds.
Anyway, all packs can benefit from some sort of frame. A light internal frame, such as a frame sheet or pad, works well for light loads. A heavier frame sheet, thicker/stiffer pad, or, stays works better for mid range loads. External frames work better for heavier loads. What is *not* explained when you buy a frameless pack, is this does not save weight in and of itself. Rather, it saves weight *indirectly* by allowing the dual use of a sleeping pad (in whatever arrangement, tube, fan-folded, or structured) as a frame for lighter loads, ie, usually up to 20-25 pounds.

My conclusion is that load lifters are still needed on “frameless” packs for loads of ~20 pounds, because any experienced hiker knows he needs the support of some sort of internal frame. It really doesn’t matter that a pad is used or a “dead weight” frame sheet. The hiker will most likely use some sort of internal frame (or in the case of Gossamer Gear or other packs with pad pockets, a light duty “external” frame.) Load lifters, will help stabilize the load against collapse.
In the case where the shoulder straps come even with the frame, pad pockets or sleeping pad, clearly some compression of the pack will help to maintain stiffness against both front and back collapse as shown.

David Chenault
(DaveC) - BPL Staff - F

Locale: Crown of the Continent
pack fit on 12/06/2012 07:04:04 MST Print View

"It's really too bad we can't have the variety of packs available via cottage industry in stores to try out. I have never fitted packs but have fitted running shoes for people thousands of times and there is no replacement for testing side by side and comparing the deviation of every model. Unfortunately, retailers are sticking their necks out to carry that kind of inventory."

Well said sir.

Dave U
(FamilyGuy) - F

Locale: Rockies
Re: External on 12/06/2012 08:24:16 MST Print View

"Carries so much nicer than a HMG Windrider which gets all the press these days."

Ooh...ya, no.

Generalizations are nasty. Did you not see the posts on fit?

I know you had one of the original ones. The Windriders use the stays from the Porter and even the same belt for the 3400 model.

Edited by FamilyGuy on 12/06/2012 08:48:09 MST.

Martin RJ Carpenter
(MartinCarpenter) - F
re: pack fit on 12/06/2012 08:27:33 MST Print View

Indeed, especially as its so important and can be so seemingly randomly individual. I certainly find the idea that it can be done using purely back length/waist size somewhat entertaining.

I wonder how many measurements it'd take to get custom packs fitting genuinely well on a reliable basis. Or why I'm a randomly problematic case :)

We actually get vaguely lucky in the UK in that the only people who import some of the cottage industry American packs are an internet based operation who also effectively have a showroom in their warehouse.

So I could, for instance, discover that - the massive range of sizes non withstanding - nothing that ULA did fitted me well.... In fact my main pack for the moment worked much better when I'd removed the lumbar pad and switched to a more flexible back system.

jerry adams
(retiredjerry) - MLife

Locale: Oregon and Washington
Re: pack fit on 12/06/2012 08:38:25 MST Print View

It would be helpful to try a pack in the store, but

Do you really need to load a pack up and carry it on a trip to know if it's right?

David Chenault
(DaveC) - BPL Staff - F

Locale: Crown of the Continent
re:re: pack fit on 12/06/2012 08:58:32 MST Print View

"Do you really need to load a pack up and carry it on a trip to know if it's right?"

Yes.

Jason Elsworth
(jephoto) - M

Locale: New Zealand
How Packs Work on 12/06/2012 15:07:05 MST Print View

"Do you really need to load a pack up and carry it on a trip to know if it's right?"

When buying cottage packs I have resigned myself to having to try them in the field and then sell them on Gear Swap if they don't work out.

Mary D
(hikinggranny) - MLife

Locale: Gateway to Columbia River Gorge
How Packs Work on 12/06/2012 16:02:47 MST Print View

"When buying cottage packs I have resigned myself to having to try them in the field and then sell them on Gear Swap if they don't work out."

I had all my gear, plus a mockup bag (in weight and bulk) of a week's food, ready and waiting when my "cottage" pack arrived. I tried the pack on, adjusted it, loaded it up, adjusted it again, and then took a "hike" around the house for two hours with the loaded pack. I was extra careful to keep the pack clean and returnable. It was a very boring hike, but at least I knew by the end of it (when I was just too bored to go on!) that I had the right pack! Just to be sure, I tried it again the next day.

I felt that it was well worth the effort to keep the pack in new/returnable condition. At least that way, you're only out the shipping cost. If you sell it, you can't get the full price of the new pack.

Edited by hikinggranny on 12/06/2012 16:06:17 MST.

Nick Gatel
(ngatel) - MLife

Locale: Southern California
Re: How Packs Work & Load LIfters on 12/06/2012 16:33:21 MST Print View

Like anything else you need the right tool for the job. I drank the frameless kool aid and it did not taste good. For total loads much above 15 pounds the packs were uncomfortable and fragile to boot. I have gotten my gear weight so low that a couple extra pounds for a real internal frame pack still keeps me well under 10 lbs PBW and often near SUL. Plus I can carry a couple weeks of food and a gallon of water comfortably. No need to frequently interrupt a trip and go back into civilization and muck up my solitude for supplies.

I disagree that all packs need load lifters. If the pack extends much over the torso and if the weight changes the dynamics, then lifters work if they are properly adjusted. Lifters don't work well if they are not connected to a frame extension. I 2nd the comment about checking out McHale's website. I researched for 6 months before buying my LBP and I thought I knew a lot about packs given all my years of experience and research during those years. During the fitting process Dan taught me a lot about packs. The biggest thing was how to adjust the stays... and most important was that his stays are so strong that even though my spine required quite an extreme bend in the stays, Dan's stays will not compress or collapse. Also you will see that his lifter set-up is meant to be removable including the by-pass harness that adjusts the lifters.

My McHale Bump has very comfortably carried 35 lbs and it does not have load lifters. The LBP also does extremely well with the load lifters removed and 35 lbs. This is the most I have carried with either pack.

Dan Durston
(dandydan)

Locale: Cascadia
Ohm on 12/06/2012 16:35:53 MST Print View

"Ohm has the frame inside now."
Normal Ohm is still external. Ohm 2.0 has the frame inside.

"Ooh...ya, no.....I know you had one of the original ones. The Windriders use the stays from the Porter and even the same belt for the 3400 model."
I still I have it. Waterproof is awesome. The stiffer stays are good to hear, as the original ones are much too soft. For whatever reason(s), I have to pull them out to unbend/warp them occasionally.

Regardless of those changes, IMO the stays are located too close to the center of the pack. They don't connect to the hipbelt wings that well, which limits what this pack could otherwise carry.

While I'm critiquing:
- the foam backpad should be removable so it can be fully utilized
- the Y-strap/bear canister system up top is a pain when not carrying a canister and should be removable. I cut it off.
- the internal seam tape peels off over time
- lower side compression straps interfere with side pockets
- the buckles on the roll top should be male on one side, female on other, so you have the option of buckling the top shut to itself (normal dry bag style) without using the side straps. This is needed when pack is very full.

Some pros:
- external mesh is nice and durable
- fabric is great, although non-white would be better (turns brown).
- hipbelt pockets are well done

Edited by dandydan on 12/06/2012 16:42:55 MST.

Dave U
(FamilyGuy) - F

Locale: Rockies
Re: Ohm on 12/06/2012 16:44:44 MST Print View

"They don't connect to the hipbelt wings that well, which limits what this pack could otherwise carry. "

Don't need to. The belt has rear stabilizing straps that suck the lumbar in.

FWIW, my Mchale pack does not have the belt attached to the frame. This is an internal frame we are talking about. The belt only needs to be attached to the frame for an external.