Design and construction of the Black and White pack

Dimension-Polyant DX-40.

It’s been over three years since I started making whole packs mostly from scratch, and I’ve learned an enormous amount through all the hiking, packrafting, skiing and especially combinations thereof I’ve done since.  I don’t care to count all the exact iterations the various packs have gone through, but as of today it numbers at least a dozen.  None of them, save the most recent, still exist.  I’ve learned to go into each new pack, however expensive the fabric, with two equally important but contradictory assumptions.  First, that I will try to make it perfect and (usually) design it to be an undying answer to as many of my requirements as possible.  Second, that odds are another will soon enough take its place, and therefore experimental features will end up building my general body of knowledge.  Perfection is an ideal, not a thing which can be arrived at.

Last of about six sketches for this particular pack. 

Patience is the best aid I’ve found for good pack design and construction.  The North Fork pack died the death of too-many tweaks and the resultant compromises back in February, and I knew I’d need another largish pack.  Since then I’ve doodled when the mood struck, pondered fabric options and features, and let things ruminate until the time seemed right.

I’ve developed fairly specific preferences as far as pack dimensions are concerned, and that drove everything else.  Eleven inches is as wide as I care to make the back of a pack, any more feels clunky.  Nine or ten inches seems about the max depth, any more puts weight too far back in those inevitable moments when packing is less than careful.  I liked the super-skinny 7″ front (and back) panels of the race pack, and decided to see how a combination would work.  I made the pack 40 inches tall to add capacity, and because I prefer a draw cord closure and use the addition height to roll things down and keep water out.

I picked DX-40 to familiarize myself with a new fabric, and because adding a bit more cut resistance to VX-21 would make it just about perfect.

Side panels with daisies and compression straps.  Streak on the left is from a botched cutting mark.

I used the beavertail, back and side pockets on past packs intermittently enough that I decided to do away with them this time.  Instead three daisy chains will allow for just about anything (deer legs!) to be strapped on when necessary.  Three compression straps rather than two are also an experiment; they should be more secure with skis and such, and provide better compression.

Sides and front panel joined.  Note line of stitching on the front, location of the anchor for the internal compression strap.

Another experiment and nod to the heavy loads this pack will occasionally carry is the internal compression strap.  A nod to Cilogear, though my old Dana Arcflex Alpine had one as well.

Internal compression anchor on the front panel. Black thread bar tacks are invisible against the webbing, and hidden on  the outside by the daisy chain.

The back panel and harness are obviously the most labor-intensive and precision part of making a pack.  Torso length and shoulder strap symmetry and angle demand particular exactitude.  I copy the later two off the 2011 Golite Jam, which suited me perfectly.  Torso length I still struggle with; on this pack it is 21.5″ from the bottom on the panel (including seam allowance) to the top of the curve in the middle of the bottom of the shoulder strap attachment panel.

I’ve taken to attaching harness components first to a fabric panel and then in turn to the main panel for several reasons.  This way makes it easier to get good strength with a conventional home machine which cannot bartack through foam, webbing and stiff fabrics with abandon.  The absence of seam lines on the main panel is a bit more weatherproof as well.  Finally, it’s easier to line things up exactly right.

One of the weak points of the North Fork pack was the hip belt anchoring, not the belt itself or the construction strength, but it’s ability to grip the wearer.  Ergo the lumbar pad on this pack, which also allows for modular hip belts and thus pack adaptability.  To build it I laminated a sheet of plastic to a sheet of very dense 1/4″ closed cell foam.  Both inside and outside are VX-21, the outer a textured variant which should provide lots of friction.

A handle is nice for a heavy pack.  This one is big enough to grab with mittens, and was tacked on with a half twist so it stands out all the time.

The frame sleeve is 30D silnylon (from the stuff sack of the Haven, in fact), and the top flap closes with a lot of velcro.  Eleven inches wide, 24 tall.  This design is simple and adaptable, and will take a framesheet for heavy loads and a folded foam mat for light ones.  The other end of the internal compression strap is anchored with multiple bar tacks under the flap.

Pack completed and internal compression strap in action.  Note hydration port on the lookers left.

The devil of pack fit is in the details.  Those observant will have noticed (from the drawing) that the side panels tapered from bottom to top for the first twenty inches, but only towards the wearer.  I’ve found that this biases the pack towards the body and helps quite a bit with good carry.

Notice the slanted top and bottom compression straps, and how the topmost connects with the internal compression panel.

The pack bag weighs 27 oz.  The Mountain Hardwear Alpine hipbelt of which I’ve become so fond will be used for heavy loads, and is 6.4 oz in medium.  The MH Thruway belt shown above is 3.5 oz, though I’ll build a comparable one that’s a bit lighter when I care to do so.  My folded, 20 inch by 24 inch by 3/8 inch foam pad is 5 oz, and my framesheet with stay (from a Black Diamond Demon) is 12 oz.  More options can be designed as needed.

Mainly I’m very happy both with how the design turned out and with my comparative efficiency in building it.  I took a bit less time to make this much more complex design than I did that first pack over three years ago.

Please ask any questions whatsoever in the comments.

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23 thoughts on “Design and construction of the Black and White pack

  1. That’s nice. You finally nailed the positioning of the side compression straps! 😀 Looks like a real fine pack. I like the panel arrangements, especially the long sloping back (seen from behind you). I too have come to the same conclusions about the proportions. Depth and width limits, leaves height to build on. In fact, as I write, my pack waits for me packed and ready for a weekender, now only filled to shoulder height, but having spare space for winter setups.
    Question. What is the difference between cranking down on a internal compression strap (á la Cilo) versus an external (for example Golite Jam)? The connection point is virtually the same.
    How does the hipbelt and lumbar pad connect? Just slide in and hope it stays put, velcro or sewn? Is the slot the same height as the hipbelt or can the belt move up and down?

    Packbuilding is lovely.

    1. There’s about 4″ by 6″ of velcro behind the lumbar pad. Theoretically it would allow for 2-3″ of vertical movement, but I’ll always have the belt as low as possible. The length of the lumbar pad was driven by what seems to fit me the best.

      The internal compression on my Dana worked by compacting the heavier 2/3s of the load and pulling it really aggressively towards the back. Additional lighter stuff can then be loaded on top before closing the pack The framesheet is 24″ tall, but the stay is only 20″, and there’s a cutout in the middle. Cranking the internal compression thus creates a bit of head space (not needed on this pack), and the flexing on the framesheet against the strap creates some dynamic tension which really stabilizes things.

      At least, that’s the theory and my experience with other packs.

  2. It’s beautiful. Looks like a perfect fit for you. What’s the pack capacity? 60 – 70 L or so?

    1. Probably around 75L stuffed totally full. There will be times I’ll want more space, but I decided that those are infrequent enough, and the downsides of a huge pack substantial enough otherwise, that making it possible to lash stuff on would be a good trade.

  3. Gorgeous pack! I’m gathering thoughts and input for a pack I’d like to build and there is some good stuff here. Thanks a ton!

  4. Dave, that is some damn fine craftsmanship. I’m hoping this pack sticks around for a while. It looks like it will be quite useful.

  5. Looks excellent. I just started working on a DX40 pack a couple days ago….DX40 is awesome stuff (although not much fun to cut).

    1. Thanks. I’ve thought about making some and selling, but that would be too much work and take the fun out of the while affair.

  6. Brilliant craftmanship! Since a few years I’ve been looking for the ultralight apline pack up to 35L and no more than 400 gr.
    I’m a climber from Poland. Could you send me some more details how to make such a pack, please? Or you can just do such a customized pack?
    regards,
    Pawel

    1. Welcome Pawel. I’ve got a lot more posts on pack construction, if you search under the MYOG category at the bottom of the page. I’d be happy to answer questions, too.

  7. Well, I’ve got one question. Since I don’t have a sewing machine, I wonder if you could make a customized pack if I give some spec.?
    Now I have an Arc’teryx Cierzo 35, but I’m not satisfied.
    best regards,
    Pawel

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