For a long wall, two pieces may have to be spliced together. This is called a scarf joint.
5.1. Position both mouldings, as they will be on the wall.
5.2. Find the nearest stud before the intended splice point and mark.
5.3. Cope the end of the moulding that will butt against the wall on your right. Make sure it is longer than needed for the splice.
5.4. Measure ¾” past the stud intended for the scarf joint and mark the other end of the piece.
5.5. Set the saw for a 45° angle and cut.
5.6. Nail the piece to the wall and ceiling.
5.7. Measure the second piece up to the backside bevel of the first piece. This is the shortest or ceiling side of the first cut.
5.8. Cut the second crown moulding.
5.9. Measure back and cut the other end square
5.10. Push the two angled ends together and nail the scarf joint first before pushing the squared end into place.
5.11. Measure, cut, cope and position the crown moulding for the last wall.
Both ends will have to be coped as the end of the Wall #1 is squared, like the end of the Wall #3.