Topic

How to make a sternum strap that slides along piping?

Viewing 25 posts - 1 through 25 (of 29 total)
PostedJan 22, 2014 at 6:00 pm

I have a North Face rucksack without a sternum strap, and would like to add one on. It doesn’t have any webbing running along the top of the shoulder straps, and the straps themselves don’t have much lateral stiffness so when I try a simple wrap-around system it collapses the strap. I think the best solution would be something like this:

I can’t find the parts or instructions on how to make something like that. I’m guessing you sew some nylon around a rope? Does anybody know where I can find some instructions or buy the parts?

Thanks!

D S BPL Member
PostedJan 22, 2014 at 6:11 pm

I had a hunting pack that used a sternum strap with the piping arrangement and it came apart. Thank goodness it was almost new and I got it replaced. So, I think adding the webbing and relative strap fixtures would be a better fix. YMMV!

PostedJan 22, 2014 at 6:40 pm

If the strap is stiff enough I agree, but this thing is so thin that grabbing it by anything but the inner edge will deform it. I think my other option is to sew it permanently and forego the sliding function.

PostedJan 22, 2014 at 6:47 pm

I've never seen the hardware for sale, except on alibaba. I've looked for them for a while. If you're willing to buy a few thousand of them, that might work. The ones I've had and have have something stiffer than rope as the piping, I'd expect a plastic rod or something similar.

PostedJan 22, 2014 at 11:16 pm

Ok, so assuming the sliding idea isn't going to fly, how important is it that a sternum strap be able to move up and down? Has anyone just sewn it in at a particular height?

Jesse Anderson BPL Member
PostedJan 23, 2014 at 12:29 pm

I guess you have to ask yourself, how often are you moving the sternum straps on on your other packs. As for me, once I got the sternum strap adjusted where I like it, I've never moved it yet. I don't see much of a need to be able to continually fiddle with the height of my sternum straps.

Art … BPL Member
PostedJan 23, 2014 at 12:55 pm

" Ok, so assuming the sliding idea isn't going to fly, how important is it that a sternum strap be able to move up and down? Has anyone just sewn it in at a particular height? "

this is what I did to the 3 packs I've made. its the simple solution.
just take the time to really figure out where you want to place it before sewing.
works fine for me.

PostedJan 23, 2014 at 1:06 pm

You don't need adjustability unless you need to fit more than one person. All packs I have made except one I've just sewed the sternum strap in place – and that's not just for me but for my kids and for a couple other people as well. No issues. The one pack I made with an up-and-down adjustable sternum strap I have never moved it.

I always wait until the very last to sew the sternum strap on so I can test fit the pack with some weight in it to determine the comfortable location.

Bob Gross BPL Member
PostedJan 23, 2014 at 1:45 pm

I think that most of the adjustability needed is in the length of the sternum strap, not the height of it. Some simple sternum straps use a buckle for adjustment, just like in the photo. Others have an elastic segment in series with the buckle. The buckle does the basic length adjustment and then the elastic takes care of your chest expanding with respiration. The elastic segment is backed up by a longer piece of strap for strength, because ultimately the elastic weakens from age.

–B.G.–

PostedJan 23, 2014 at 6:50 pm

Lots of Da Kine backpacks have the sternum strap system you depict in the first photo.

I harvested the relevant fasteners and beads from an old crapped-out Da Kine bag yesterday. The bead is indeed just nylon wrapped around cordage, about 5/32" thick.

PostedJan 23, 2014 at 7:26 pm

i might do the wrap thing, let it collapse the strap as it's not in an area that a wide/flat strap does anything save look cute, and thusly have the adjustability to determine to proper place to sew it.

along the lines of that looking cute … too high a strap looks entirely completely lame.
it just says all the wrong things.

cheers,
v.

PostedJan 24, 2014 at 7:15 pm

You could use tape to sew some acetal rectangular loops on top of the piping at different heights, and thread the sternum strap through the loops to provided at least a few height options.

Or instead of using the loops or piping, you could have tape sewn like a flat daisy chain onto the strap next to the location of the piping so that there are a number of openings for the sternum strap to slide into. If the strap goes under and through one of the openings in the tape, and back upon itself to hold fast with Velcro, the shear strength of the connection would be quite strong. But there is always the concern about the effect of water on the Velcro in a deluge. Maybe tri-glides would be better than Velcro to hold the strap to itself.

But if you want something continuously variable, you might need the specialized hardware some posted about. Anything that locks is probably going to be a little bulky and might rub against the chest.

Bill Townsend BPL Member
PostedAug 13, 2014 at 3:54 pm

Any luck by anyone finding this hardware?
Cord or plastic rod seems likely to me, but the hardware itself is the key. It's specs will dictate the type of slider needed.

For the OP or anyone stumbling across this-
http://www.seattlefabrics.com/slides.html sewing a strip of webbing or grosgrain to the face of the strap is the traditional way to accomplish the adjustable strap. I placed my bar tacks about 4" apart, any further and the sternum strap starts to tug the webbing too much.

I dislike the non-permanent (slotted) ones as they pop off easily.

FWIW- I like to adjust the sternum strap as I vary my pack carry through the day and carry anything from 10-30 pounds of gear. When the load is heavier having the ability to slide things around is a big help.

They are also quite nice for fastpack/running type levels of fit with a vest type system.

The slider on pipette seems the most elegant solution and many packs are making the switch- hopefully it trickles down to us soon.

PostedAug 27, 2014 at 11:15 am

108 used Da Kine backpacks on eBay right now. Many will have the sought-after fastener. Many will sell for chick-feed.

Sam Haraldson BPL Member
PostedAug 27, 2014 at 3:22 pm

Are you settled on the idea of only using this type of attachment system? If not, the standard add-on type of sternum strap may not weigh any more than the type you're asking about and will almost certainly be easier to add.

Two tri-glides, a couple short lengths of webbing, a male buckle, and a female buckle and you're set. You can either use tri-glides that you sew into place or use ones that are removable.

sternum strap

Bill Townsend BPL Member
PostedSep 5, 2014 at 10:14 am

Bit sick of that system, I am moving into more fastpack style designs and wanted the ease and greater range of adjustment. I've found if I go much more than 4" of play in my lighter fabrics/webbings that the traditional system (especially the removable shown) either pop off after time or pull the webbing too much.

The sew in's with a stiffer/heavier webbing work for me to about 4", which is good on a regular pack, but not so much on a fastpack.

Yar, I could scrap some off some used stuff, and that's a good suggestion. Was hoping that as this system has gained traction it may have leaked down to the MYOG crowd.

Roger Caffin BPL Member
PostedSep 5, 2014 at 3:26 pm

Hi Tim

I know the hardware exists, but what brand and where can one buy it? Care to share?

Cheers

Tim Marshall BPL Member
PostedSep 5, 2014 at 3:52 pm

The friend who told me about this supplier asked me to keep it to myself so I will honor that. However its bulk purchases only.

Plastic buckle may carry them

-Tim

Oliver Nissen BPL Member
PostedSep 5, 2014 at 5:00 pm

Three parts to this:

1. Nexus call it the Pipe Doc: http://na.itwnexus.com/sites/default/files/100%20PipeDoc%20Sternum%20Slider%20new.pdf

Try finding a well stocked distributor in your neighbourhood among these:
http://na.itwnexus.com/content/list-distributors

2. Then for the piping core… 4mm or 3mm dia HDPE welding rods perhaps? You'll have to experiment thickness in combination with…

3. The cover! My guess would be a thin nylon twill tape – more friction than grosgrain's ribs and not as slippery as a Polyester quality. But this is just conjecture.

Please keep us posted with how that all works out. I've got a few samples of the PipeDoc but the little motivation I have to do anything with them is outweighed by all the experimentation needed to get the system working.

Oliver

Bill Townsend BPL Member
PostedSep 11, 2014 at 3:15 pm

http://www.woojinplastic.com/products/detail/326/category:sternum-system

The woojin system appears to be the one I am looking for. The clip on piece is solid, not a two part one like the nexus system.
The one Tim didn't mention, looks pretty close too.

I am looking at the Osprey Poco series kid carrier and found the woojin name. The piping appears to be wrapped in a grosgrain ribbon, the "stiff" "heavy" version of it, or perhaps a light flat webbing.

What I don't feel in there are the fins. Not really dying to take mine apart to verify they are trimmed off, the shoulder strap is beefy by UL standards but not beefy enough that I wouldn't be able to feel them unless they are super thin. So it's possible it is a piping system after all- the clip seems to have it's own model number separate from the piping.

SO… anybody know of a distributer for Woojin Plastic. Website is a dead end, US facility is "coming soon"

Or maybe Tim or someone else can not tell me of a source for one of the other brands :)?

Nexus, Woojin, and John Howard all seem to carry something close enough if a source can be found. I can't imagine any of them would allow a one off order without an account, even in bulk.

PostedSep 19, 2014 at 7:25 am

Baby Bjorn offers a functionally similar (sliding-on-the-piping) system on the back of some of their baby carriers.

Similar but a lot thicker gauge and more robust.

See the back view of the woman in the photos:

Viewing 25 posts - 1 through 25 (of 29 total)
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