How do I fix/repair a broken joint on a figure?

It looks like there's a long piece that connected two balls that go into sockets on either end. If that's correct, and you want to repair the long piece so it doesn't break again, you want to pin it. That means drilling into both sides of the break and putting something stronger to act as a bridge through both holes. There are bunches of tutorials on how to do it like this one https://spikeybits.com/2020/04/this-is-how-to-pin-metal-miniatures-the-right-way.html (just an example, you can probably find better ones)

My dumb ass read figure as finger and went wtf? Just go to a hospital.

during transit that the head/neck joint piece broke in two.

Uh, send it back and get another one.

Lots of good advice in this thread. As far as what glue i recommend this site. Make your best guess as to the materials and then check which glues work best. https://www.thistothat.com/

Super glue would probably work. Scuff up the surfaces with some sandpaper a little bit, then you should be golden!

I use a tiny drill bit to make a hole in the centre of either side of the damaged joint, then cut a piece of metal tubing (hobby shops sell them) or a piece of plastic such as filament from a 3D printer (getting a ~1cm piece of PLA from your local library is probably free) to use as a pin to fit into the holes and reinforce the joint. Then once you are happy with the fit, glue it all together. If it is really tiny, you may not be able to pin it and then glue might be your only hope. Depending on the weight of the parts and material, crazy glue is usually pretty good for most situations. With plastics, where I need it to grip right away and hold its own weight, I like Testors modeling cement. Way better initial hold than even the gel crazy glues.

E6000 epoxy glue is the best all around glue out there.

I don't know shit about plastics. But I am rewatching the show for the 3rd time.

I suspect the plastic snapped on those two portions left and right. Maybe?

That’s one suggestion when fixing a plastic thing. If there was a brittle fracture (think silly putty when you rip it apart fast), then you’ll get this “distorted plane” surface somewhere. It’ll be smooth to the touch, not glossy, and its edge/profile won’t make sense as part of the design.

Why am I micromanaging your perceptions? Sorry. I mean look for spots where the plastic snapped.

If you find the corresponding one, the other half of that snap, it’ll fit perfectly like a puzzle piece. You can glue that. I think. It’s been forever since I’ve tried this. Might be you need to rough up the surface first, to ensure glue remains in the gap. Otherwise that brittle snap is too perfect and the gap volume is zero, meaning all the glue gets squeezed out.

I think. Again, over a decade since I’ve repaired any plastic thing, that I can recall at the moment.

Also, you could probably drill out some holes (probably wanna find some ancient greek style geometry trick to line them up. I suspect you could use intersecting lines to find the corresponding point on both pieces; definitely don’t eyeball it because the slightest misalignment in joining will make a ridge a person’s fingers or thumb can detect).

Anyway drill out holes on both sides that line up, and put a little threaded metal cylinder (screw with head and tip cut off) in. Make that join really strong. Probably better than just sanding it to make glue space.

Anyway if it didn’t brittle fracture, or if it came apart just not brittlely? Word? But ductilely, like silly putty pulled apart slow, then you’ve got a whole different thing. Probably gotta heat the plastic and re-form it. Talk to someone who does cars about reshaping plastic then.

Or maybe the little plastic nipple snapped and you need to replace it with a new one. It looks softer so harder to glue? Maybe?

Hope you enjoyed my rambling. Good luck. Who’s the action figure? Is that He Man?