What is the best method of pattern development to layout a right cone?

The radial line method is the best approach for pattern development when laying out a right cone because it allows for accurate representation of the cone's surface area and facilitates easy transfer to the sheet metal. This method involves drawing lines from the apex (top point) of the cone to the edges of the base circle, creating triangular sections that can be used to lay out the true shape of the cone's lateral surface.

Using radial lines ensures that the angles and proportions are correct since this method accounts for the cone's geometry directly. Additionally, it simplifies the process of calculating the dimensions needed for the cone's development, making it more efficient for creating the actual pattern on the sheet metal.

Other methods, like triangulation from the base view, offset method, and diagonal method, can be less effective for cone development due to their inherent limitations in representing curved surfaces and accurate angles. The radial line method, therefore, remains the preferred choice for this type of geometric shape.