The class 216 lok from the start up range doesn't come with a NEM coupler socket. As I use ROCO universals (40397 pack of 50) where possible this is a nuisance. So I've 3D printed a NEM socket and pin arrangement that allows fitting of a NEM coupler socket.

While it works fine there are two issues.

1. The best layout I could get with a functioning NEM system allowing for a ready change of couplers gives a length increase of 2-3 mm over the already quite protruding stock coupler.
2. I fit the pin from below and super glue it in place, making the future removal/replacement of the new coupler socket a potential problem for those without ready access to a 3D printer. For those who have a 3D printer it is just a case of slicing through the old one with a scalpel and printing a new one.

IF you are just wanting to PERMANENTLY fit an alternative coupling (like me) you could slice 2mm off the NEM socket and the barbs/hooks of the NEM coupler and superglue them together - that fixes the length issue.

Anyway, design is public on TinkerCAD under my username of revmox.

Previous designs for other start up items can be found on this forum. Working on a solution for an early V36 next.