Assembling of spacer ring on the chuck

  1. Attach the tool handle to a vise.

  2. Unscrew the chuck and gear unit.

  3. Put the chuck and gear unit in the collar. Attach the collar in a vise.

  4. Remove the chuck with a chuck key.

  5. Assemble the spacer ring to the gear unit.

  6. Assemble the chuck and tighten with a chuck key.