Hinged hipbelt attachment strength and method

[Doug Coe]

I’m working on version 2 of my pack. It has a hinged hipbelt and I got an idea of how to attach it from Paul McLaughlin, using Velcro on straps (on the hipbelt) and anchor straps (on the pack).

The back and bottom of the pack are one piece so there’s no seam between them to sew the anchor straps into. So I have them going up the back—on the bottom they’d get wear when I set the pack on the ground.

The weird thing is, when worn, the tri-glide pulls up on the stitching holding the anchor straps. Not ideal.

What would be a better way to do this? Or do you think it’s OK as is?

(Yes, in the third photo the hipbelt buckles are on the wrong side of the belt!)

[John Dallas]

looks like you have done well. I like the design.  My suggestion:

You do have an issue. The tri-glide will likely rip a hole in your pack. The straps need to go below the tri-glide instead of on top because the weight of the pack is pulling down and out.  (If this does not make sense I can send you a drawing showing the stress on the pack and tri-glide.)

This would place the strap on the bottom of pack and get some wear. I don’t think that would be near the issue you are going to have with present set up. A way around this is move the location where it connects to the belt to the middle. This would allow the strap on pack to be moved up. Alternatively, you could cover the strap and reinforce part or all of bottom of the pack. And you might consider putting tri-glide in the middle with part if strap going below and part going up. This would reduce even more stress that the tri-glide puts on the spot. You would need about half as long a piece of strap going up as goes down.

[Paul McLaughlin]

Doug – the way I did it is the straps that hold the looplocs are sewn to the bottom of the pack. Never had any issues with wear, the pack went through a lot of use by myself, followed by my son using it for many trips at Point Reyes Summer Camp backpacking. The hipbelt wore out, but not the attachment.

[Doug Coe]

Paul—That’s great to hear. Not having tried making a pack before I was leaning toward being conservative. Now I’m going to try it your way.

Did you use plastic looplocs? Or aluminum? I have steel ones from OWF because I was worried plastic wouldn’t hold up.

[Doug Coe]

John—Thanks for the ideas.

[Paul McLaughlin]

Fastex looplocs. Carried 40 lbs regularly in it, over 50lbs a few times with skis and boots strapped on when walking to the snowline for ski trips.

 

[R]

Another option is the run a piece of webbing sideways where a back panel / bottom panel seam would be, then put your triglide anchors in to that.  Seems common to do this across the upper portion of the back panel to re-enforce shoulder strap attachments – it’s worked for me.

[Jerry Adams]

another possibility is to just sew hip belt to pack

attachment mechanisms result in the pack slipping up and down relative to the hipbelt.  As you’re walking along.  If the pack is heavier…

[Doug Coe]

Paul—Yeah, I would have gotten plastic looplocs from OWF but they only had a generic brand version.

Rene—Great point…though it will add even more weight! I’ll chew on it.

Jerry—True, I could just sew the hipbelt on, but I want to experience this flexible style and see how I like it.

Does anyone know a source of Fastex brand 1″ looplocs?

[R]

Doug,

I once did a bunch or prototyping packs in Tyvek, and I tried a few iterations of this type of belt attachment.  It almost afforded too much mobility of the pack.  I think you’ll really want hip tensioners to stabilize the pack.

And as Jerry said, there’s slippage – or maybe rolling is a better word for it.  I’d start out with a sleeping bag in the bottom of the pack and other gear loaded on top.  Then things would slip, and the sleeping bag would have migrated a few inches as the whole pack sort of slid under it, creating a new lowest point that was actually a few inches up the front panel.

Here’s a way to visualize it.  Attach a thread to the toe of a sock.  Put a golf ball in the sock and hold the sock up by its opening.  Now lift up on the thread.  The golf ball will roll away from the toe.  If the pack is the sock, the thread is the belt attachment.

A frame will fix this, but I’m assuming you’re frameless here.

When I eventually got to a nylon prototype, I made a wrap around belt, and attached it with a big square seam.  I held a ruler across my lower back where the belt sits, to see how wide the flat part of my back is.  So that was the width of the square, and it spanned the height of the belt.  This way the belt isn’t loading the seams by pulling the pack forward around the sides of my hips – it really just has the vertical shear force from the weight of my gear.  This is a frame pack, but the frame is just 2 carbon rods down the edge seams of the back panel – the ends are an inch or two away from the seam attaching the belt.  This gives good load transfer to my hips while still allowing plenty of mobility.  I added hip tensioners but tend to leave them loose.

 

[Jerry Adams]

yeah, rolling

and I can see why you would want to try a flexible connection, good experiment

[Doug Coe]

Rene—I’m using two aluminum stays: 1/8″ x 1/2″. The tops are at the load lifters’ top anchors and the bottoms are at the hipbelt attachment points. If you look closely at my photos you can see a bit of the black lines going up from these points.

I’m taking most of my design inspiration from Paul McLaughlin who has made a similar pack. Also, Rogue Panda has a hinged hipbelt, as seen in their YouTube video.

Also, @roamer from Nunatak Down Gear has made a pack for himself with this design element.

They each have different ways of attaching the hinged hipbelt. I love everyone’s ingenuity!

[R]

Oooh – I completely missed that.  I saw the black lines but didn’t realize what they were.

In that case, I agree with Panda and @roamer – put the sleeves on the outside and use webbing wrapping up under the end of the stay to attach the belt.  Also lets you seal the sleeve seams inside the pack.

Interesting move by @roamer terminating the shoulder straps on the belt.

And that’s probably enough out of me on this :)  Enjoy your project and let us know how it turns out!

[James Marco]

Doug, As far as the hipbelt attachment goes, this is relatively old school. I have one pack from the 70″s that has this “upside down” attachment. I removed the hip belt then when putting it back on I flipped it over by mistake. The attachments work OK.

[nunatak]

Thanks for bringing up my project! This system works exceedingly well; you should have good success too.

I liked it enough to be experimenting with a frameless version this winter . So far just okay. A lot depends on packing the dense, heavy stuff low, which I like to do anyway.

Another MYOG sack

 

Plateau Pack v.3

[Doug Coe]

James—I too have an old pack like that: a Trailwise external frame pack (bought on the recommendation of Colin Fletcher’s book).

@roamer—Very nice work, once again! That front pocket looks like the one on the Drop 40L by Dan Durston.

[Murali C]

Maybe you will have to reinforce the back where the belt will touch the bag as there will be increased abrasion from the belt constantly rubbing against the back? I think belts stitched to backpacks do not suffer from such issues.

[Stumphges]

I really like the idea of attaching a robust/full wrap belt like this to allow for some independent motion of belt and packbag. I’ve been tempted to order a Rogue Panda pack for this reason.

For those of you using this style of attachment, how well does it work to allow freer movement of the pelvis in relation to the shoulders while walking? While scrambling?

[Doug Coe]

Stumphes—I’ll have to get this thing sewn up and take a long hike to know!

[Stumphges]

Haha, OK Doug, thanks!

[Author]

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