04-14-2011, 01:04 PM
The coupler that I like for steam pilots is the Kaddee #4. It has a squarish section at the back where a coil spring would be installed for centering, but it also has a very small hole in the shank just in front of the "centering chamber." I just cut off the square in the back as well as the little tang, and mount it in the pilot of steam engines with a 00-92 screw through the small hole. Unfortunately, I just tried to order some of them and Kaddee has discontinued them and the left over stock is sold out.