HOW TO DEVELOP A CONE
1. Make a cone using the command “CONE”. To create a cone, first indicate the radius of the base and then the
height.
2. Measure the circumference and slant height of the cone.
Circumference = 2(pi)(radius)
(Slant height)^2 = (radius)^2 + (height)^2
i.e. If your cone has a radius of 5 and a height of 10, your:
a. circumference would be = 31.41592653589793…
b. slant height would be: 5^2 + 10^2 = 125 therefore the slant height is sqrt(125) or 11.18033988749895
3. Use the “CIRCLE” command to create a circle with a radius equivalent to the slant height. Preferably round
up to the nearest tenth or hundredth.
i.e. If the slant height is 11.18033988749895, round up to 11.18 or 11.2.
4. Make sure your OSNAP or snap functions are on, and then using the “LINE” command, start from the center
point of the circle and create a line at 0 degrees with a length equivalent to the radius.
5. Create another line using the same command and create a line with a length of the radius of the circle, and at
an angle derived from this formula:
(Circumference of the base of the cone/ circumference of the new circle with r=slant height) = α
α * 360 = angle corresponding to the arc that should be drawn from the circle that is equal to the circumference
of the base of the original cone
The line drawn at that angle would divide the circle into two arcs.
6. Using the “TRIM” command, trim the arc that is not included in the angle created by the two lines.
7. Create another circle, congruent to the circle at the base of the cone. Move it using the “MOVE” command
and make it tangent to the arc at only one point, and the circle and sector do not intersect at more than one point.
8. Add tabs to the circle using the OFFSET, DIV(IDE), and LINE commands to create tabs on the circle and
one of the radii that make the sector