How to 3d spring using autocad

step 1. :

helix in command line

step 2:

specify the center point of base of the spring your going to draw

step 3:

specify the base radius or Diameter of the spring

step 4:

specify the top radius of spring.. it'll same value unless your spring is of conical shape

step 5:

specify height of the spring

step 6:

to see the spring you have drawn in isometric views.. type 3d orbit

and enter.. or click the icon showing 3d orbit...

now rotate the drawing with help of your mouse..

step 7:

now change the view of figure,if you have started to draw the spring in top view then change to front view...

or according to the view you've started to draw... final view should be like as shown in fig.

Step 8:

Now rotate the model slightly... so that you are comfortable to draw a circle over the edge of 2dspring.. (check fig.)

step 9:

draw a circle of required pitch you wanted.. using command C or circle or clicking the icon..

step 10:

now type command SWEEP and then select the circle (for Object to sweep)..

Step 11:

select the helix or spring for the sweep path...

Step 12:

After doing it... you can see the spring as 3d wireframe like the one shown below...

Step 13:

to see the 3D SPRING in shaded view.. type  SHADE in command box and enter.. you will get the 3d spring.. :)

Enjoy... :)