JBL Tune 7XX swivel joint

This part is designed to replace the RIGHT swivel joint on JBL Tune 7XX series headphones - made for and tested on JBLTune 770NC but it will fit several other models with similar cup forks. It can be used for the left side as well by mirroring the part before printing.

It is probably best to print this part ROTATED 90° so the pivot pin stands perpendicular to the bed. Use a wide brim - 12 mm worked for me - and add supports to both the bottom as well as the sides to make sure it doesn't wobble while printing the pivot pin. Use PETg or something stronger, 100% fill. You may need to drill out the hole through the pivot pin after printing using a 3mm drill.

Prepare the cup fork by removing (i.e. breaking out) the cable guide which sits inside the middle of the fork to make room for the base of the replacement part. Remove what is left of the broken pivot pin and drill a 7-7.5mm hole for the new pin to slide through. Now push the printed part into the centre of the fork, making sure the pivot pin goes through the hole. Push it up all the way so that the groove in the pivot pin sits about 1.5mm above the surface. The part does not need to be glued and it is better not to do so since it might break again and need replacement.

You'll need to remove the metal pin which holds the broken-off part of the pivot pin from the pivot hinge in the headband:

to do that you'll need to drill a 1mm hole exactly opposite where you see the pin on the inside and push it out:

The pin can be re-used to attach the new pivot so don't loose it.