Repairing Rubber Cord Necklaces

Hello everyone and Happy Holidays!

This fall I ordered the 2mm rubber cord necklaces from Rio Grande
with the sterling clasps. They were for some special order necklaces
for a good customer. Three of the neck clasps have come undone from
the rubber (the rubber breaks off inside the clasp). I can remove the
broken piece and have tried, unsuccessfully, to reglue them. What
frustrates me is the cruddy quality of these necklaces. I have not
contacted Rio about replacements due to the heavy holiday load of
late, but plan to do so in the new year. Has anyone else had this
problem? What did you do to repair them? Epoxy hasn’t helped and I
wasn’t sure which glue to use that wouldn’t harm the rubber. Luckily,
this customer is really understanding and hasn’t demanded a refund,
but I want to fix this as soon as possible.

Thanks for your help!

Tammy Kirks

Hi Tammy,

I would recommend JB Weld available at Home Depot. It works great.

Happy New Year,
Reba

What you want is a toughened cyanoacrylate adhesive, they are
designed to bond rubber and plastics to metals or other rubber or
plastics. My favorite is Black Max (Loctite 380) I use this to make
rubber “O” rings from stock rubber cord. It makes a bond that is
quite strong and flexible. They also have several other versions of
toughened cyanoacrylate with various properties so check out the
website below.

Jim

James Binnion
@James_Binnion
James Binnion Metal Arts

360-756-6550

I’ve had similar problems with the ones I purchased from Stuller and
elsewhere. I gave up using them or having anything to do with them. I
have repaired them with epoxy and not had any problems with them
coming out, but I find that the weak spot where the end caps are is
going to be a problem no matter how many times they are fixed. I
also find that it doesn’t take very long before the rubber becomes
quite stiff and the cords no longer hang nicely on the neck. Once
they are stiff they also break more readily, usually at the end cap.

Jim

it doesn't take very long before the rubber becomes Quite stiff and
the cords no longer hang nicely on the neck. Once They are stiff
they also break more readily, usually at the end cap.

Several years ago I found some cording material in a sporting goods
department. I don’t know exactly what the material is but it seemed
like a neoprene. It’s original use is to repair duck decoys. I
figured if it would take that kind of abuse it would work for a
necklace. So far, I have been pleased. It’s about 3mm.

Bobbie Horn

I also find that it doesn't take very long before the rubber
becomes quite stiff and the cords no longer hang nicely on the
neck. 

Jim, how long have you found to be not “very long”? I did a necklace
with a rubber cord about 6 1/2 years ago, and when I last saw it
(about a year ago) it was still just as flexible as when it was
brand new. I don’t use it very often, but it just seems to fit with
some things, so I have some more, too, that looks just fine, although
I suppose it’s all from the same original purchase. Do you mean a
longer time than that? Obviously I want it to be nice for a VERY
long time, but I would assume “not very long” to be a year or two, or
even less, and this has certainly passed that. Just wondering what to
expect. Maybe, too, it depends on what type you get, and some last
longer than others.

Thanks,

Lisa
Designs by Lisa Gallagher

These “rubber” cords are not rubber at all but one of a family of
plastics called elastomers. There are several families of elastomer
(butyl, nitrile, silicone, polyurethane, fluoroelastomer, etc.) and
dozens of formulations. Visually there is no way to tell which is
which but the properties vary greatly with the family and
formulation. The trick is to find out which one(s) are suitable for
use as a necklace cord. I can just about guarantee that the folks
selling this cord did not do any research and just bought black
“rubber” cord at the best price they could get. So it would not
surprise me at all to see different elastomers used in the same
parts sold at different times by the same vendor. Some of these
materials are affected by sunlight and become brittle, some loose
elasticity as the plasticizers in them evaporate, some cannot
tolerate petroleum oils others are sensitive to alcohols and on and
on. Anyway to find a long lasting cord for this purpose you will need
to do some research.

James Binnion
@James_Binnion
James Binnion Metal Arts

360-756-6550

how long have you found to be not "very long"? 

Lisa, the original post wasn’t mine, but here is my experience. I
have had neoprene cords last 6 years, and some last 6 months - same
size neoprene all purchased from the same supplier within a couple
of months. The six year ones are still fine and the six month one was
returned to me totally brittle and almost rigid ( sound effects here

  • muted screams in background) I have also had some returned after a
    year or so where the neoprene had become soft and crumbly around
    where i glued and riveted the catch on ( screams fading). The glue
    was the recommended locktite 501. The supplier tells me that their
    supplier is probably sourcing from different places, but it all
    looks the same, just behaves differently over time. Needless to say,
    I have stopped using neoprene cords with my work unless the customer
    insists, and I do tell them the experiences with this material.
    Obviously other people are having similar experiences, and BTW I
    might add that my supplier is reputable - in fact the only actual
    jewellers supplier in this state. Sorry, no answers here except
    maybe try another supplier- just adding to the discussion,

Christine in Sth Australia

how long have you found to be not "very long"? I did a necklace
with a rubber cord about 6 1/2 years ago, and when I last saw it
(about a year ago) it was still just as flexible as when it was
brand new. 

I’m not Jim, but I’ll chime in. Among the aspects of my business, I
do trade repair work for a local jewelry arts gallery that carries
the work of many fine art jewelers. Some of these artists enjoy
using the black rubber cords in their necklaces, and I’ve had to
replace a several of them when the cords broke, usually near to where
they’d been glued into their clasps. Usually, on inspection, one
finds tiny cracks in the rubber where it’s aging, which is why I
don’t just clean out the clasp and reglue the end for a slightly
shorter necklace, but instead, replace them. Some of these repairs
have been on fairly new pieces, but most have been pieces that were
made within the last ten or twelve years. One was about fifteen years
old. I’d guess that a reasonable life expectancy for the rubber cords
might be around ten years if the piece is worn carefully. If not, of
course, a customer can break almost anything pretty quickly, if they
set their mind to it… It’s not just the rubber that ages, by the
way. The glues often used to stick the cord into the clasps also ages
and gets more brittle with time, and with use, the rubber gets dings,
tiny cuts and scratches, abrasions, etc, all of which can lead to a
breakage.

cheers
Peter

Hello,

I would recommend purchasing your cord from Marco Rubber by the foot.
I’ve been using the Buna-N (Nitrile) for years and have had not one
problem. Check it out. O-Ring Cord and Kits | Marco Rubber & Plastics | Custom O-Rings Supplier

Reba

Thanks, Christine, James & Peter for your insight into rubber cords.
It seems, then, it’s tricky to tell whether the cord one has is the
“good” kind or not, and even then it’s inherent in the construction
of such a piece, with a glued-on clasp, that problems could happen
because of the glue, too. I will decide for now to rest assured that
the one piece I’ve made with the cord will wear happily for a good
while. If eventually there is a problem, hopefully no major damage
to the center piece itself will take place & if they contact me, then
I can offer to replace the cord out for them. The cord was purchased
apparently a popular design choice there, and I’d like to assume that
they have experience with the cord they buy and are pleased with it.
Knowing the uncertainties associated with it, though, I may hesistate
before using it again. Is leather by chance a better choice when
wanting that sort of black cord look? I suppose it’s not necessarily
as smooth & sleek in appearance, but it is at least similar. There’s
still the glue aspect where the clasp is attached, but if the cord
itself is at least more reliable, then that’s something to consider.

Thanks!
Lisa
Designs by Lisa Gallagher

There's still the glue aspect where the clasp is attached, 

Lisa, one more thing that helps is to rivet through the cord and the
catch after gluing - just a bit more security,

cheers, Christine in Sth Australia