Wonder if anyone would be good enough to tell me how they get the ends of their coupling rods circular at the ends? I see LBSC method of putting a pin in the vertical slide or whatever and hand holding them with your hands against the side cutters on a slot drill but this seems a bit hairy fairy scary broken wrist to me. There must be a better method.
Filing buttons are just a couple of slices parted off a rod of teh same dia as the outside of your rod end and drilled to the same size as the hole, some people harden them I just use mild steel as it is.
You then slip a pin through your rod hole, a disc either side and file away, when teh file hit sthe discs they act as rollers and stop the file cutting any deeper.
It may seem a pain making them but keep them and you will save having to make them the next time, you will soon get a good collection