My Morse 3400 sewing machine tensioner came unassembled. How do I fix

Hi, most thread tension assemblies on old sewing machines work on the same basic principle:

Generally there are two or more steel discs arranged on a shaft, together with a spring which provides a variable pressure on the outside of one of the two discs, the pressure from the spring forces the two discs together such that they grip the thread.

By varying the pressure exerted by the spring, the tension in the upper thread may be increased or decreased.

The video shown via the following Youtube link gives information on a typical thread tension assembly that is similar to that on your Morse.

https://www.youtube.com/watch?v=ABYrdfC4...