Deburring expert LaRoux Gillespie acknowledges that specifying and measuring burrs is an arcane art, but he disagrees profoundly with the majority of manufacturing engineers who believe that doing so is a waste of time and money. Gillespie learned the importance of this skill early in his career as a manufacturing engineer for the old Bendix Co. (Kansas City, MO).
The lesson came when 0.020-inch diameter pins coming off a screw machine and a subsequent deburring operation had failed inspection. When Gillespie viewed a photograph taken at 200X magnification, he found that the base of a burr too small to be seen by the naked eye had spilled over the edge. Although the deburring process had sheared off the top of the relatively thick burr, a slight deformation at the base had remained. The anvil of the gages used by the machinists and inspectors was resting on this tiny protrusion and showing the parts to be too big.