Hi DIY!
My headphones of many years recently broke. My first response was to attempt to glue them back together with super glue (ethyl 2-cyanoacrylate) however that didn’t seem to hold. Not even a little bit.
I then did a bit of searching and found that Sony often use ABS plastic in headphone manufacture, so presumably these are ABS. I then read super glue should work okay on ABS, however there seemed to be no bonding happening at all.
Do any of you have any tips for the best kind of glue or epoxy to bond these plastic parts back together and get the music flowing again?
I plan on wrapping the joints in thread afterwards, for additional durability. But first I need to get them bonded.
physical reinforcement is a good suggestion lots are coming up with. If it’s not too late, I’d recommend doing that with something that dissolves the ABS instead of an adhesive. ABS dissolves readily with a few solvents, like acetone. Get physical reinforcement in place, and IF you do not need any bulk filler, just use a solvent like acetone to literally melt and repolymerize the plastic back together. As long as there’s no new gaps or new voids, the physical reinforcement should leave it stronger than the original. At least after all the solvent evaporates away.
If you need gap filler or bulk reinforcement, two part epoxies are definitely the way to go, though make sure to use something quite flexible or it’ll just crack off the next time you drop them.
Speaking of physical reinforcement, when my headphones broke in a very similar way I was able to use cable ties to secure them back together. Ugly but it worked.
The headphones I currently use (on my head right now) also have physical reinforcement, but instead of zip ties it’s just a thin tensile wire I had lying around. Tied it around a cylinder piece that broke off that holds a rotatable insert, superglue, and lots of extra wraps encased in superglue… and it’s perfect! … outside of where I was dumb and got glue between the rotatable faces and now it binds up a bit, but otherwise great. Replacement parts would’ve been like $35+.
… I guess all of that is to say, physical reinforcement is excellent when it’s adding strength as opposed to replacing strength! (similar to OP, the superglue is a bit brittle for a one to one toughness fix).
A few people have recommended acetone now. I originally ruled it out due to the wire running through one of the hollows (not wanting to damage the insulation) but I’m thinking I might try adhesive on the piece with the wire and acetone on the other. Thanks!
This is a tough one, mainly cause of the strains experienced in that position. If you’re daring, maybe try some acetone to “melt” and refuse the plastic. I don’t think an adhesive is going to be much help unless you cake it in epoxy, and reinforce the stress point.
Unfortunately there’s a wire running through one of the broken pieces so melting is probably a no-go because I don’t want to melt the insulation. Thank you though!
The insulation on wires is not abs.
Whatever you do, don’t break that wire, it’s nearly impossible to DIY repair.
I would make some metal rods to insert in the holes left in the hollow plastic. Epoxy those in place on both sides to reinforce the joints which will have stress on them. I think that is the only chance you have of repairing broken plastic like this with little surface area to bond. You could look around and find some nails or something to cut up.
@punksnotdead@slrpnk.net I would suggest carbon fiber rods or aluminum, ferris metal could interfere with the bluetooth radio depending on their shape.
I seriously doubt that.
I’m just a lowly embedded engineer working on BLE on aarch and other SOC kernels.
yeah, everyone is an engineer on Lemmy. there is ferrous hardware all over BT headphones.
And I’m a 30 year veteran EE who designs a lot of high speed and RF gear. There is zero chance ferrous metal rods to repair the headphones as described would have any meaningful impact on the Bluetooth connection.
You’re technically correct that metal in the vicinity could possibly have some measurable impact on the 2.4GHz radio, but your theoretical scenario is a practical absurdity.
Somebody suggested wooden dowels so I’ll probably try that just because I have scrap wood lying about anyway and it’s easy to carve into shape. Thanks!
Great idea! I’ll give that a go, thanks. Reinforcement rods, adhesive, and thread wrap around the outside should surely be enough
Might be able to find some wire in an electrical or automotive store. 20 guage is about a millimeter or less, 12 guage is between 2 and 3 mm. Do you have calipers to take a measurement?
Wire Coat Hanger might fit, will be harder so a better reinforcement.
No calipers, but I have random bits and bobs lying around that I can just trial and error until something fits. Thanks!
This is just called plastic welding and it’s fantastic
I’ve done some awful things with various 2-part epoxies, maybe try one of those with a piece of dowel in the square holes? Not sure exactly what you have to work with there but that might give you a little extra support from inside while your glue of choice just has to keep the rod from slipping. Start with one a little larger than the holes and sand the sides flat until it fits with a little extra space, add glue, press together, let it cure.
For bonus points, you can scratch up the inside of the plastic with a rolled-up piece of coarse sandpaper or something to try and give the glue an extra foothold.
Awful things?.. Dare I ask?
I’ll definitely try reinforcing with a dowel or metal rod though, thanks!
Nothing that interesting, just enough to gain a reputation as somebody who can do solid in-the-field temporary fixes when a real specialist isn’t available. One that comes to mind is a portable toilet that was delivered (clean and empty, thankfully) with a split in the side of the tank. Guessing they got a little too close to the trees on the way in and the driver wasn’t paid enough to care. There was another one in good condition so this wasn’t a critical issue but still an inconvenience.
Wasn’t too bad, I could just about span the full length from pinkie to thumb tip and there wasn’t any missing material. More than I’d trust glue or tape alone to hold for long though. Drilled a series of holes in parallel lines on either side of the split and stitched it shut with paracord before painting over it with a 2-part epoxy as a strong liquid barrier. Don’t remember what kind it was but it remained somewhat pliable when cured so I figured it wouldn’t turn brittle and crack. It held for the duration of the job and didn’t leak as far as anyone could tell (and if it had, the terrain would have made that obvious).
Not the most exciting story of heroism under pressure but I went from learning about a problem to finishing the fix in about 45 minutes with fading daylight.
I’ll be honest, you’re probably not going to be able to fix those to a degree that I’d trust. Some headphones are reparable and have replaceable parts, and that isn’t one of them. I’ve had really good luck with Audio-Technica and Beyer Dynamic in that department, but most of their more sturdy and repairable headphones aren’t very portable.
If the adhesive route fails, it looks like there are replacement parts available, but your mileage may vary when it comes to the source. Not seeing anything official, but ebay has a few hits: https://www.ebay.com/itm/204942975498
Might also try just calling Sony support, but iirc their support is fairly shit.
Came to basically say the same thing. Parts also on AliExpress, looks like the same pictures from eBay so might be the same products. “Fixing” the plastic joint that has so little surface area and is mangled as much as it is seems like it would be dubious at best.
If it were me, I would be looking at buying a replacement bracket first, and if that didn’t pan out, I’d probably be looking to 3d print something that would function as a new bracket or an entirely new headband.
I am but a poor student so I’ll try and repair it first, but it’s good to know there’s parts out there if absolutely necessary - thanks!
If it’s ABS (which most thugs are) try methyl ethyl ketone to melt it back together.
Just a dab of MEK will melt the plastic, but it evaporates/dissolves quickly. Once you apply it press the pies together firmly for a few minutes, then let it cure for a while after that. The bond should be as strong as it was from the factor. Then if you want apply some JB weld for extra strength.
Gloop gets used in 3d printing. It physically welds the bonds together on a molecular level between 2 plastics.
Gloop is just acetone and tetrahydrofuran. That shit is toxic AF.
That looks like toast.
3D printed replacement parts might work. If you have a maker space around you, you might be able to find someone to help you with the drafting/CAD.
Ouch, I used hot glue for mine but its not great at holding to the surface, I just had a massive surface to make use of and pretty much made a ring of glue around the break. Doesn’t look like yours would work with that sadly.
So, probably don’t go with hot glue.
Noted, thanks though!
You can glue it, it won’t work. When you’ve tried all of them, get a plastic staple gun and make it ugly, but fixed.
I bought a cheap Temu plastic repair welder (melts in a little metall pin) - they actually work and the results are surprisingly strong.
General purpose tip for Gluing:
Isopropyl Alchohol in a spray mister will speed up Superglue bond time from minutes to seconds.
Mixing glues can be very useful. For example, I’ll use Epoxy for the hollow insides but a drop of Superglue where pieces fit together to hold the pieces together while the Epoxy cures overnight. UV glue is fantastic for that because it cures instantly. But a drop of Superglue with a spritz of alcohol works good too.
Cyanoacrylate accelerator is not IPA. It’s a mix of acetone and amines. You are getting a weak effect from the water in the IPA.
I didn’t say it was accelerator but it works like accelerator. This is the solarpunk forum where you are supposed to recommend hacks.
I didn’t think of mixing glues, nor have I heard of the alcohol spritzer thing - I might give it a go. Thanks!
Loc-Tite Plastic Bonder has worked well for me in these situations, but sometimes it just doesn’t seem to take well; other times it holds better than the original plastic does. Worth a shot?
This looks like Loc-Tite’s version of the JB Weld Plasticweld. If I can’t find any JB then I’ll give this a go, thanks!







