Starrett 53058 Tubular Micrometer 32 Inch Range

Product Description

The STARRETT 53058 is a mechanical tubular outside micrometer designed for large-diameter and long-reach measurements up to 32 inches. It reads to a graduation of 0.001 inches with an accuracy of 0.0001 inches, making it suitable for high-precision dimensional inspection work. The micrometer uses a friction thimble for consistent feel and repeatable readings. Ten extension rods with a 3/8-inch (9.53 mm) diameter allow the technician to build up to the full 32-inch range. Each rod features hardened and ground anvils that are adjustable for length. The satin chrome finish reduces glare during reading. Machinists, toolmakers, metrology technicians, and quality-control inspectors are the primary users of this instrument.

The STARRETT 53058 is applied in shop-floor measurement, quality assurance, and precision tooling applications where standard fixed-frame micrometers cannot reach. It is well-suited for measuring large bores, outside diameters of rolls or cylinders, and other large workpieces requiring traceable dimensional verification. The tubular rod design keeps overall weight manageable while spanning long ranges. With 1.5 inches of thimble travel per setup, the instrument covers a broad measurement range through sequential rod additions.

Key Features

• 32-inch total measurement range via 10 interchangeable extension rods
• 0.001-inch graduation with 0.0001-inch accuracy
• Friction thimble for consistent measuring pressure and repeatable readings
• 3/8-inch diameter extension rods with hardened and ground anvils adjustable for length
• 1.5-inch thimble travel per rod configuration
• Satin chrome finish minimizes glare and corrosion

Compatibility

Designed as a precision tubular micrometer for general metrology and machine-shop use where large outside-diameter measurements up to 32 inches are required.

Installation Notes

Setup and use should be performed by a qualified machinist or metrology technician familiar with tubular micrometer assembly and calibration practices. Before measuring, verify that all rod joints are fully seated and that the anvil faces are clean and free of burrs or debris. Calibrate against a known standard or setting ring before taking critical measurements. Store the instrument in its case with rods disassembled to prevent stress on the joints.