N Scale Couplers
thingiverse
These N scale couplers can be used to replace the rapido style ones that comes with rolling stock. They operate okay with most other couplers and should get you by until you can get a commercial coupler installed. The photos show a switcher that is using a short shank box style connector, there are inverse couplers so you can flip them over and get a different height. The caboose has T shank couples installed. I drilled a small hole and added a brass pin to the underside of these after printing and cleanup. I recommend you file or sand all edges slightly after printing for best operation.
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