Bobbin extractor to suit Elna sewing machines (star series, air electronic series, Lotus series, Contessa, etc).
Original spares are no longer available.
Note the originals have a thin shaft that the spring screws over. This is where they always break. As a result, I have omitted this shaft, and replaced it with an M4 threaded hole to accept an M4 grub screw (6-8mm long). The spring then threads onto the grub screw.

To repair/replace the bobbin extractor, you need to remove the top cover of the machine (2 screws), and if it has a handle such as on the air electronic or lotus machines, also remove the clip holding the handle onto its shaft.
On the top of the bobbin extractor tube (near the light) there is a screw that screws into the top end of the extractor spring. If you are unsure which one it is, try lifting it up: the screw extractor crew will lift up under spring tension (if the old extractor is still attached), or without tension if it has snapped off as they usually do.
Remove the screw from the spring. Attach the printed extractor to the spring. Feed the spring in from the bottom. Insert a long screw into the extractor spring tube and screw into the end of the spring just enough to grip the spring so that you can pull it up, and then replace the long screw with the actual screw removed previously. If you screw the long screw too much into the spring, it will be very difficult to get out again. It is better to screw it in less and fail a couple of times rather than overdoing it and having a problem getting it out.
It is not uncommon for the spring to be mangled: unfortunately I don't know the specs for a replacement, so be gentle with the original spring.

Creality

Ender 3

No

No

0.15mm

20%

Print with the threaded hole on the bottom, no supports needed.
Note I cleaned the threads out with a 4mm tap, but if you are gentle, this is probably not necessary