Mitutoyo 178-392 Small Hole Detector for SJ-210 Surftest

Product Description

The MITUTOYO 178-392 is a small hole detector accessory designed for use with surface roughness measurement equipment. It mounts to compatible Surftest portable surface roughness testers and allows technicians to perform roughness measurements inside small-bore features and restricted geometries where a standard stylus cannot reach. The detector features a 90-degree tip angle, a measuring force of 4 mN, and a stylus radius of 5 micrometers. It is installed and used by calibration technicians, quality control professionals, and precision measurement specialists working in manufacturing and inspection environments.

This accessory is suited for surface roughness inspection tasks in industrial and laboratory settings where internal bore or small-hole surface finish verification is required. Typical applications include incoming inspection, process control, and final QC on machined components with tight interior features. The 178-392 is intended for professional use with bench-top and portable surface roughness measurement systems in high-precision manufacturing environments.

Key Features

• 90-degree tip angle allows access to small holes and restricted surface geometries
• 5-micrometer stylus radius for fine surface texture measurement
• 4 mN measuring force minimizes contact stress on delicate workpiece surfaces
• Overall length of 60.70 mm for reach into confined measurement areas
• 9.00 mm overall diameter body fits standard detector mounting on compatible testers
• Compatible with the SJ-210 Surftest portable surface roughness tester

Compatibility

Designed for use with the MITUTOYO SJ-210 Surftest portable surface roughness tester. Intended as a replacement or supplemental hole-detection accessory for Surftest portable surface roughness tester systems.

Installation Notes

Installation is performed by qualified metrology or quality control technicians familiar with surface roughness measurement equipment. Power down or disable the tester before attaching or removing the detector to avoid stylus damage. Handle the stylus tip with care, as contact with hard surfaces or improper storage can alter the tip geometry and affect measurement accuracy. Follow the instrument manufacturer guidelines for detector mounting and calibration verification after any accessory change.