DIMENSIONAL CONSULTING

Now we have a basic diameter specified on the cylinder. Therefore the profile of a surface callout controls size as well as cylindricity. The entire surface must still fall between two coaxial cylinders 0.1 apart. However, now one of those cylinders has a fixed diameter of 10.1 and the other has a fixed diameter of 9.9... Once again we have a profile tolerance without a datum reference. The tolerance points to a surface, and it has a circle at the knee of the arrow. That circle is the 'all around" symbol. The all around symbol tells us that the tolerance applies all around the part, but only in one view... If we have a basic dimension to the surface instead of a coordinate dimension, then the profile tolerance controls the location as well as the orientation and form.