These coupling are designed to fit between coaches or wagons as a semi permanent connection, I have also done these as magnetic couplings where you can easily disconnect your coaches or wagons. But for those people who keeps there rakes of coaches and wagons together most of the time then this is what these have been designed for.

These items have been designed to be printed on a 3D Resin Printer due to size and detailing. I also recommend you use a resin that is more suited to this application, I used AnyCubic ABS Like resin as its a little more flexable and stronger than standard resin. I have been using AnyCubic ABS Like resin on couplings for 18 months and have found them very reliable.

Resin used:

AnyCubic ABS Like Resin Pro 2 https://amzn.to/4dVZoEU (Amazon) Associate Link

Please be aware that 3D printed couplings will not be as strong as injected molded couplings, with using these you will probably need spares on hand in case of any break. With the ABS-like resin I have had minimal failures but nothing is perfect.

I have also found that different rolling stock from manufacturer need different length of couplings so I have produced these in 5 lengths, the lengths are measured from NEM socked face to NEM socket face. The sizes included are 16mm, 18mm, 20mm, 22mm and 24mm.

The examples in the pictures were printed on an AnyCubic Proton M3 3D resin printer. As mentioned I used AnyCubic ABS Like Resin, I’m not an expert on what resin you should use.

https://www.cgtrader.com/designers/PJD1974?referral_id=3218445

My website has lots of useful info.