A spherical radius can be produced and checked if drawn and dimensioned with care.
As shown in Figure 1, it should be noted that the radius of the spherical end of the cylinder is one-half the diameter of the cylinder, and the tolerance limit for the radius of the spherical end is one-half of that shown for the cylindrical surface.
On some parts, the radius of the spherical end will be larger than the diameter of the cylindrical surface of which it is the end, as in Figure 2.
A note explaining the concentricity required for a spherical section or surface is always recommended.
Where a spherical surface is not required over all the end, as for a mating surface, a flat should be allowed and dimensioned as illustrated in Figure 3.