These are basic instructions for making a spring of similar shape.
1. Determine the height, radius, and the number of rotations in the spring. The number of rotations is total number of times the wire makes a full circle.
2. Draw a line that corresponds to the height of the spring.
3. Enter the "helix" command.
4. Create the helix around a curve.
5. Enter the number of turns. (In the image below you see two helix with a 6" radius, one with 12 turns and one with 6 turns.)
6. Enter or draw the radius.
7. If you need to add a top loop or extra length to the spring add the follow steps.
8. Add extra lines and make sure they begin at the end point of the heilix by using the end object snap.
9. Connect ALL of the curve/line segments with the join tool.
10. Turn on the Edit points and refine the shape of the wire by removing all sharp corners and edges. (Rotate and view the wire form in different views to make sure you edit out all of the kinks and create a smooth, accurate shape.) In the above image the helix on the right has sharp edges and will not make a smooth spring. The helix on the left has been smoothed out by transforming the lines from sharp corners to smooth curves. This take a bit of good craft to make sure that all of the lines are now smooth working in all views.
11. Create a cross section of the spring. (This is typically a small circle.)
12. Place the center of the circle perpendicular to one of the end point of the wire spring.
13. Using the sweep 1 tool create sweep the circle along the wire path. (Select the Untrimmed Miters option;)
14. Cap the ends and make the shape a solid.