Sunnen says its GR-2245/2241 bore gages combine rugged design with precise, reliable measurement to 0.0001" for large-part applications. The gages bores range from 2" to 12" (50.8 to 300.0 mm) in diameter and as long as 24" (600 mm) with appropriate attachments. Special models can measure bores as long as 65" (1,650 mm). Available with analog dial readout or electronic indicators, the gages provide replaceable carbide gaging points to withstand wear conditions with rough workpieces or abrasive materials. Wear-proof ball cranks offer long-term repeatability and retractable or non-retractable gaging points to prevent scratching the bore interior.
Adjustable centralizers ensure proper positioning over the entire diameter range, resulting in accurate centering. A twist action adjusts gaging tension, enabling the head to go smoothly in and out of any size bore. A right-angle attachment is available for more difficult viewing conditions, while blind-hole probes offer measurements to within 0.5" (13 mm) of the bottom.
Gages with electronic indicators are accurate to ±0.00012" (±0.003 mm) with 0.00005" (0.001-mm) resolution for scaling calculations, tolerance judgment, data holding and general comparison measurements. A data output cable enables direct transfer of bore measurements to a computer, facilitating SPC data collection at multiple points in a bore during long production runs. Gages can also be preset with upper and lower tolerance limits for GO/±NG judgments.
The electronic indicator displays the spindle's absolute position using an absolute linear encoder capable of relocating the origin after the power is turned off for quick-start, multi-point measurement. The positive/negative count resulting from the spindle's up-and-down movement can be toggled, and the indicator face can be rotated 330 degrees to ease reading at different angles.