Very High Speed Lap with Negative Lift Effect.
DEPARTMENT OF THE AIR FORCE WASHINGTON DC
Pagination or Media Count:
A rotary lapping system which contains a construction and mounting of grinding pads called tesserae which act to produce a negative lift or suction through hydrodynamic action with an abrasive slurry liquid is disclosed. The rotary lapping system uses a plurality of negative lift tools, each of which is composed of a square base of metal, a rubber sheet bonded to the base and four brass tessera bonded to the rubber sheet. Each tessera has a plurality of equally spaced, parallel grooves forming the grinding surface and the four tesserae are bonded to the rubber sheet to leave a relatively wide space, or slot, between each of the tessera. Four negative lift tools are attached around the outer edge of a metal ring, equally spaced, and the metal ring is bonded to a rubber ring which is bonded to the base of a power driven dish-like member for hodding a grinding slurry to be fed to the grinding surfaces. The tessera construction causes a negative lift, or suction, to produce very strong cutting pressure with more rapid material removal without distortion of, or harm to the workpiece. The negative lift is the result of the particular mounting of the tesserae, which cause the tesserae at the leading edge of the rubber sheet to present a negative angle of attack to the abrasive slurry liquid during rotation.
- Fabrication Metallurgy
- Machinery and Tools