What did you do to your trains today?

Is there any way I can get a copy of the file for the talk and action coupling?

Absolutely, here are the individual parts, you can print what you need or the whole thing.
https://drive.google.com/drive/folders/1...sp=sharing

It uses the metal axle from an original TnA coupling, but pretty much anything with the right diameter will work as a replacement. It needs some filing to work as smoothly as the originals. I have mixed parts between the 3D printed one and an original but it was a little rougher, my dimensions are not perfectly matched I don't think. It's still about as fragile as the original ones are too.

I was actually also thinking of doing the battery covers, although they may be better suited to molding instead of 3D printing.