Mitutoyo 3428A-19 Dial Drop Indicator 4 in Lug Back

Product Description

The MITUTOYO 3428A-19 is a plunger-style dial drop indicator designed for precision dimensional measurement in shop, field, and production environments. It covers a total range of 0 to 4 inches with a dial graduation of 0.001 inches and a range of 0.1 inches per revolution, making it suitable for inspecting runout, flatness, parallelism, and surface alignment. Accuracy is rated at plus or minus 0.005 inches. The indicator uses a jeweled bearing for consistent, repeatable stylus movement and mounts via a lug back for secure fixture attachment to magnetic bases, surface plates, and transfer stands. Machinists, quality technicians, and tool-and-die professionals are the primary users.

The 3428A-19 suits dimensional inspection tasks in manufacturing, job shops, and maintenance settings. Its 4-inch range accommodates larger workpiece variations without resetting the indicator mid-inspection. The 0-100 dial reading is straightforward to interpret at any point in the range. The lug back and clamp-on base mount type allow it to integrate into standard indicator fixtures and custom holding arrangements commonly found on milling machines, lathes, surface plates, and CMM setups.

Key Features

• 0 to 4 inches total measurement range for larger-span inspection work
• 0.001 inch dial graduation for fine, readable resolution
• Plus or minus 0.005 inch accuracy over the full range
• Jeweled bearing construction for smooth, consistent stylus travel
• Lug back with clamp-on base mount for rigid fixture integration
• 0.1 inches per revolution range suits standard dial indicator setups

Compatibility

Designed as a standard plunger-style dial drop indicator compatible with lug-back mounting fixtures, magnetic base arms, and clamp-on indicator holders typical of shop and inspection environments.

Installation Notes

Installation is performed by quality technicians and machinists familiar with indicator fixture setup. Secure the lug back to the mounting fixture before applying any measuring force to the stylus. Ensure the indicator spindle is oriented perpendicular to the surface being measured to avoid cosine error. Do not exceed the stated measuring force or drop the indicator, as jeweled bearings are sensitive to impact.