Zeiss MMZ-B system with VAST gold active scanning sensor is shown here measuring components of thrusters used in marine vessels at Thrustmaster of Texas.
The Zeiss CMM is used mostly for fi nal inspection of thruster components, including lower and upper outdrive housings, used in large marine vessels. The lower outdrive housing boards are about 170" (4.3-m) long, and are very dif- fi cult to measure with tolerances of about 0.001" (0.03 mm) on geometric features. Large upper outdrive housings, over 100" (2.5-m) long, have numerous feature tolerances where motor and gear drives are located that interface with planetary gear systems and have very tight position tolerances of less than +0.002" (0.05 mm). Geared rings with a 90" (2.3-m) diameter also have tolerances of +0.002". “With the new Zeiss gantry CMM, inspection time of a lower outdrive housing was reduced from three days to three hours,” Martin says. The Zeiss gantry system doesn’t need a climate-controlled room; however, its manufacturing and inspection area of the building, about 250,000 ft² (23,225 m²), is climate con- trolled. Thrustmaster’s MMZ-B is located right on the shop fl oor and has been performing fl awlessly. Because manage-