The spring mechanism, parts 1 and 2

Step 1 of 2

1. A screw that pushes the spring.
2. A mount for the spring; small metal disk.
3. The spring itself.
4. There's a hole here where one can insert an Allen key to adjust the spring pusher screw.

  Back to Step 1

Step 2 of 2

1. There's a trick to getting this whole thing together. The motor must be placed on the mount at relatively the same time that the spring mechanisms are snapped into place. Futz around with it and you'll get the idea, but prepare to be frustrated.