Pack Attachment Angle

I've noticed a lot of MYOG packs have shoulder straps attached with a seam running straight across. I've also seen many commercial packs and a few MYOG packs (i.e. the G4) that attach at an angle which mimics the slope of the shoulders. Has anyone found this to make any significant difference in the comfort of a pack?

I'm asking because I just made one (straight strap attachments), and I can't help planning my next. The straight attachment worked well, but if it could be even better, maybe it's worth the effort.

I haven't tried sewing packs, so my fitting is limited to dress bodices, where I do try to fit the slope of my shoulders. BTW, the slope is not the same on either side! Most of us are not symmetrical.

If you are making the pack especially for you, you certainly would want to do the same. I hope you can get some help with the fitting!

I think they should be angled, since if they're attached horizontally the strap will have to twist somewhat and may apply pressure unevenly to the shoulders. They can attach to a horizontal seam or webbing reinforcement, but the straps themselves should be angled. You can see how I did it, sort of, in my post in the MYOG forum titled "new pack finished."

You can experiment with different angles by taking a 4- or 5-foot piece of wide webbing, folding it in the middle to form, say, a 60-degree angle, then pin, clamp, or stitch it so it will hold the angle. Then drape it over your shoulders and see how the angle works. 60 degrees works for me. That is, each strap 30 degrees from vertical.

The placement of the strap attachment depends on whether the pack has a frame and load lifter straps or is frameless. If load lifters are used, the shoulder straps attach below the shoulder level, and the load lifters above, enabling you to adjust how much weight the shoulders take and how much the hip belt takes. On a frameless pack, the shoulders take more of the weight, and the straps need to be attached at or slightly above the shoulder line, and somewhat wider apart, similar to the old external frame designs.

Thanks for the advice, Bill. I went back and looked at your pack again, and I'm just blown away by how professional it looks. Is it still holding up well? Anything you would change if you did it again?

I haven't used it much yet, but so far so good. I've made half a dozen packs of more or less similar design over the years, and haven't had any failures. I've tried different variations, but mostly the aluminum stays in a "V" configuration with load lifters. The first pack I made was frameless, and I attached the shoulder straps too low...pretty uncomfortable even though it had a hipbelt. I also made a Ray-Way style pack, and it worked pretty well, but I have trouble getting my weight down to the point where it needs to be for that kind of pack to work.

I forgot to mention that the shape of the shoulder straps may affect the placement angle. I've tried both straight and S-shaped straps, and the 60-degree angle works for both for me, but I'm pretty skinny. It might be different for someone with broader shoulders.

One thing that I think is kind of important is to make sure the buckle at the lower end of the shoulder strap doesn't extend past the padding. That way it can't gouge your side. You can also put the buckle where the strap attaches to the lower corner of the pack, Ray-Way style. That works fine, but takes some getting used to.

Having played around with rucksack angles, largley because the straps kept falling off and i had to re attach them, i can tell you this.

Flat straps can run straight up the back and roll over the angular neck muscles on the shoulders digging in on the inside of the strap. If they are spaced adequatley and the chest strap is tight they can be quite comfortable and flat.

Angled straps can work to stop the inside side of the strap carrying the load and thus digging in. These straps are usually very curved. Because the strap run up from the pack, over the shoulder and back down the angle can be more of a hinderance, the weight and angle making the outside of the strap dig in, especially if the straps are attached close together.

Narrow distance between attachment points of the straps can mean that the straps ride onto the neck muscles on your shoulders.

Wide distance between the straps can mean that the staps are too far overand pull the arms back.

The best set up i ever had was the strapssewn to the hip belt (frameless bag) so they came directly down the torso, eliminating the pull on the arms. Cant remember the angles on the straps.

Very cool idea, attaching the bottom of the strap to the hip belt, but very untraditional. The basic concept of a pack is so simple, but when you get into the little details, it really can get complicated, especially when it has to do with the human-pack interface. The spacing of this, the angle of that, could make the differnce between a usable pack and a great pack.

Years ago, Trailwise made an external frame pack that had the shoulder straps attached at the bottom of the pack on opposite sides, crossing behind the mesh that pressed against the user's back. It might have been the first pack to use load lifter straps, but I'm not sure. It's described in The Complete Walker, edition three, I believe.

Really really complicated at just that, and it is all variable to how the pack is seated on your back. You think that the angled straps will fit the shoulder muscle on your neck, but it all depends on the angle of your own muscles, pack height weight etc. Probably pivoting straps must be best. And a hard strut at the top may stop the arms pulling off. (Fault with my pack was they had sewn through the padding giving the thread room to strech, thats another little thing i found out !)