I've had a couple of this style of plastic clip crack. Wrapping it in thread and then applying super glue seems to work pretty well. I also tried wrapping with fishing line, but it came undone pretty quickly. Just wanted to share the tip! Now if only I had a fix for when the prongs on the other half break off.
Here's another way that might work for you.
Get some PLA or PETG filament from a 3D printer. Just a few inches worth. Put it into a dremmel - leave only a half inch or so sticking out. Turn it on and you can spot-weld plastic with it. The 3D filament will basically heat up with the friction when you turn the dremmel on and press it into the clip.
PETG is harder and stronger than PLA, but both should do the trick.
I've not used a Dremel - are you clamping the filament end-on, kind of like a pencil lead? Would a drill potentially work in the same way, if so, if you can align it in the chuck properly?
Clamping? It's got a tip that you screw down around like the chuck of a standard drill. Dremmels spin at high speeds, 7000-15,000 (or more) RPM. The tip uses a small wrench to tighten down.
You stick filament into the tip. It spins at high speed. The filament heats up from the friction when you touch it to an object. It then starts to melt and bond with the object.
Thanks!
I didn't have a printer but do know someone with one, I bet I could ask for a little filament. Sounds fun to try.
Cool - You will only need a little bit for that clip.
I've also successfully reprinted clips like that with PETG. It's excellent.