Knuckle Coupler for LGB

Updated Dec 2019:
added the "V2" Opening Knuckle versions from the Motorised coupler..

Updated Oct 2017: I have added the "fixed 7 degree" version of my revised geometry couplings here. These are single piece parts, and need the lock ring to push them down firmly in the housings. It has similar "push" performance to the two part version and they do interlock, but the single piece geometry is designed to work "optimally" with my servo operated coupling, which uses the same geometry, but has the fully working knuckle.
https://www.thingiverse.com/thing:2553019.



The two piece parts were originally revised 27 Feb 2017 to provide better "push" performance, because I discovered that my original design had a fault when "pushing" a long train. When the coupling is subject to strong push forces, the old design allows the coupling to open. . (I have added a picture to show four coupled together with me pushing them together. You can see the left (old) coupling opening, whilst the righ