Replacing the buckle on a sternum strap

Those are cursed. I have those older low REI car camping folding chairs with a sliding lumbar cushion with that sliding plastic part on a rounded seam. I will never buy another piece of gear with those on it.  Never again.

Maybe just replace the strap?

Bill the part you’ve linked to couldn’t be attached to the strap, not without the piece I’m trying to attach. I could try some kind of strap that loops around the pack strap but seems like a janky solution.

That IS what I linked. It’s a replacement sternum strap.

The only difference I see between it and an original sternum strap is the sliders that adjust height of the strap. The built-in sliders stay in position after adjusting them, while the replacement strap has just loops, as you say. Takes an extra second to adjust the height if it moves.

Agreed that replacing just the buckle would be nicer, if you can.

It’s lame for most of the major pack brands using that bolt rope sternum strap. Doesn’t matter which company, they all are prone to popping off. It makes no sense to me. Is cheaper to make it that way vs the sternum strap sliding on nylon webbing strap?

Here is a different kind of replacement sternum strap. This one attaches to the vertical webbing on your shoulder strap (from MLD).

Thanks Bill, but my shoulder strap has no webbing.

How is that possible? Never mind… I’ll take your word for it. :)

In that case, the first one I linked is certain to work on any strap. I’ve got one on my old Lowe Alpine pack. It’s fine. Not as perfect as the original, but it does the job.

I believe AK is referring to this type of (cursed) shoulder strap.

If so, then the first strap that I linked would work perfectly. It would work just like the original.

I’m having some trouble visualizing the issue without a photo. The OP mentions replacing the buckle, but then there is discussion of the piece that attaches the strap to the pack, so I’m not picturing the specific problem. My confusion is that it doesn’t seem that one would need to detach the strap from the pack in order to replace the buckle. Maybe we could see a photo of the broken part that needs to be replaced, and how it is held on to the strap?

I see what Bill Budney is trying to convey- a loop of webbing goes around each shoulder strap. A buckle connects the 2 pieces. It is easy to see on this link https://a.co/d/5JuGFOU

On my last trip, someone had a Gregory pack with that kind of sternum strap. Trying to get it back on that piping was an exercise in frustration. Maybe some oil, needle nose pliers and 6 hands might be able to get it back on, but doubtful.

I took a utility strap and wrapped it around the entire shoulder strap like the one Bill linked. Crude fix that worked.

Matthew’s photo shows the type of hardware. I have a replacement plastic piece to attach to the piping, just can’t get it to attach. It’s hard plastic, with no give, so to get the opening wide enough to slide onto the piping is just about impossible. I’ve tried pliers to squish down the piping, a screwdriver to pry open the plastic while I (with my third hand) slide it on, etc. It’s utterly maddening.

I may try just looping some strap around the shoulder strap and replacing both sides of the buckle, as Bill recommended with the Amazon link. It doesn’t have any webbing, so I would guess it will just slide up and down all the time, but I’ll give it a go.

I will also be on the lookout for this type of attachment on anything I purchase – never again! That said, the pack is at least 8 years old with heavy use, so it has been good. Still, terrible design for the buckles!

There is some rope or tube material inside the piping that gives it its shape. I would just go to the very bottom of the piping and with a very sharp utility knife/razor or some good scissors cut about a half inch piece of the piping off (along with the structural round piece inside it). Now you have an open end to slide your new piece of hardware up the pipe. Use a lighter to melt the material once you are done so it doesn’t fray.

If you have the buckle, then it may be worth one last try to get it installed. Philip’s tip may work. Or perhaps soaking the buckle in boiling water may soften it?

Once you give up on the old strap, just cut it off. The strap that I linked is open-ended, so that you can loop it through the hardware shown in Matthew’s picture. The result should be good as new.

Ah, I see the confusion Bill. The hardware shown in Matthew’s picture is the piece that won’t reattach. So with that piece missing, there’s nothing to loop a strap through. The only option is to put a new strap completely around the shoulder trap. Imagine the shoulder strap with nothing on it; that’s what I have now.

Oh! The slider is broken, not the buckle?

In that case it is Philip’s plan (although I would fear reducing structural integrity of the shoulder strap), or ask the manufacturer. Or borrow a third hand from somebody. That plus softening in boiled water might get it done.

Or, as you say, use a replacement strap that loops around the entire shoulder strap. Once you find the best position, maybe you could secure it in place with a safety pin or duct tape? It probably doesn’t get much vertical stress.

“I would fear reducing structural integrity of the shoulder strap”

As long as you don’t cut any of the stitching, I would not sweat this at all.

Is the pack an Osprey? This video claims that whatever is inside the piping on Osprey packs is crushed near the bottom of the shoulder strap, so that the clip can be slid on easily at that spot. Perhaps other manufacturers do that also.

This poster on reddit claims that he was able to install the clip after heating it up for several minutes with a heat gun. Once heated, it could be pried open far enough with a screwdriver.

It’s an Osprey, but the flatter section of piping still doesn’t allow the clip to go on easily. Hmm, maybe I’ll try a hair dryer.