How to make variable spring

This is how to make variable spring
 

1. Step 1

   1.open new design
   2.draw circle
   3.draw line
   4. select pull
   5. select revolve
   
   

2. Step 2

   6. select line
   7. select circle ( select surface, not circle line)
   8. select revolve helix
   
   

3. Step 3

   9. taper angle: 30
   pitch: 7 (if circle diameter is less, in this example, circle is 6 mm)
   height: 14
   10. enter or click in the empty
   
   

4. Step 4

   11. taper angle:30
   pitch: 20
   height: 50
   12. enter or click in the empty
   
   

5. Step 5

   13.taper angle: -30
   pitch: 20
   height: 50
   
   

6. Step 6

   14. taper angle: -30
   pitch: 7
   height: 14
   
   

7. Step 7

   enter or click in the empty
   
   

8. Step 8

   Final result...