Precision is paramount when measuring internal dimensions accurately. Inside micrometers are essential tools for achieving this, offering superior accuracy over calipers in many applications. Selecting the right inside micrometer ensures reliable measurements for critical tasks in machining, engineering, and manufacturing.
- 【Range】5/16" - 6" (8mm to 150mm), Stainless Steel Construction.
- 【Using】This bore gauge expands in a hole to be measured , locks in place and then removed to determine final hole size using a micrometer or calipers. It is suitable for measuring the inner diameter of holes, such as the inside of cylinders and bores...
- 【Package】Includes 6 sets, with vinyl case
- 【Fine Workmanship】The contact point of this machinist tool is hardened tool steel and is fine ground within the final measuring radius
- Range: 0.2 - 1.2''
- Graduation: 0.001''
- Accuracy: 0.00028''. Resolution: 0.0001''
- Satin-chrome finish. Hardened & ground faces
- The combining of extension rods provides a wide measuring range. Supplied with a standard caliper gauge for zero setting.
- Diameter of extension rods: φ15.5mm. Rod Diameter: 0.61"
- Accuracy: Metric(3+n+L/50)μm, (n=number of rod, L=maximum. Measuring length (mm) [Inch]. Resolution: 0.0001"
- Each interchangeable rod is marked with its measuring range.
- VERSATILE INTERNAL MEASUREMENTS: Offers versatile internal measurement capabilities, making it an essential tool for precise assessments of internal features such as cylinders, rings, and parallel surfaces.
- VERNIER SCALE: Graduated in inch units, enabling precise internal dimension measurements. This scale allows users to read measurements with a resolution of 0.001", ensuring accurate assessments of internal features such as cylinders, rings, and parallel...
- INTERCHANGEABLE EXTENSION RODS: Offers exceptional versatility for precise internal measurements, ranging from 2 to 20 inches. This adaptability is achieved through its interchangeable extension rods, allowing users to measure a wide array of internal...
- PRECISE POSITIONING: Features a slow head travel mechanism, providing fine positioning capabilities. This design allows for precise adjustments when measuring internal dimensions, ensuring accurate and repeatable measurements. The micrometer head advances...
- Used to measure a wide range of ID measurements.
- 1" Travel mic head.
- Size in marked on each extension tube.
- Clear graduations on satin chrome finish mic head.
- Heavy-Duty - The Starrett Tubular Inside Micrometer has rigid and lightweight rods, and quick reading figures. Extension rods are made of steel tubing and each rod is marked with length.
- Hardened and Ground Anvils - The tubular comes with hardened and ground anvils. It has an excellent service life and outstanding work performance.
- Interchangeable Anvils - It is equipped with easily interchangeable anvils for diversified gaging, providing the full range in steps with a micrometer.
- The Perfect Accessory - Used in a wide variety of industries as an essential part of metalworking and woodworking, Starrett tools can be used in various applications and offers unparalleled service with execution like no other.
- Resolution: 0.0001''
- Satin-chrome finish
- Range: 1-2''. Graduation: 0.001''
- Accuracy: 0.00028''
- SKU# 303-2214
- Measuring Range: 2-24"
- Accuracy: 0.00005"X(3+N+L/2)
- (n=number of rod, L=maximum measuring length)
- Large LCD display
- Spring-Loaded travel
- Metal Alloy Jaws, Chrome finish
- Inch, Metric and Fractional Readings, Hold Function
- Quality Made - The Starrett Solid Rod Inside Micrometer Set has adjustable insulated rods marked with length, hardened and ground advils along with quick-reading figures, and provides years of reliable service.
- The Perfect Accessory - Used in a wide variety of industries as an essential part of metalworking and woodworking, Starrett tools can be used in various applications and offers unparalleled service with execution like no other.
- Meets Strong Demands - Committed in providing customers with consistent and reliable solutions, Starrett has set the standard for precision, quality and innovation. Our products are long-lasting, robust with excellent service and performance.
- Accuracy You Can Count On - Starrett precision measuring tools exceed accuracy and performance requirements of national and international standards, providing excellent fine precision tools for industrial, professional and consumer markets worldwide.
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Last update on 2026-10-16 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Inside Micrometers
Understanding Inside Micrometer Types
Inside micrometers come in several designs, each suited for different tasks. Rod-type inside micrometers are common for measuring diameters of holes and bores. They feature an extension rod that can be locked in place. Ball-type inside micrometers use a hardened steel ball for contact, making them ideal for measuring internal diameters in blind holes or where shoulders are present. S-type inside micrometers are versatile and can measure both internal and external dimensions, though they are less precise than dedicated inside micrometers.
Key Features to Consider
- Measurement Range: Ensure the micrometer's range covers the dimensions you need to measure. Larger ranges often mean multiple interchangeable rods or extensions.
- Accuracy and Resolution: Look for specifications on accuracy (e.g., ±0.0001 inches) and resolution (e.g., 0.0001 inches). Higher accuracy is crucial for demanding applications.
- Material and Durability: Micrometers made from hardened steel or stainless steel offer greater durability and resistance to wear and corrosion.
- Ratchet Stop/Friction Thimble: This feature ensures consistent measuring force by slipping or stopping when a set torque is reached, preventing over-tightening and inaccurate readings.
- Included Accessories: Some sets come with extension rods, calibration standards, or protective cases, adding value and convenience.
Choosing the Right Size and Style
The size of the object you intend to measure will dictate the required measurement range of the micrometer. For general workshop use, a mid-range set might suffice. For specialized tasks, you might need a micrometer with a very narrow or very broad range. Consider the accessibility of the internal surface; for deep bores, longer extension rods are necessary. If you frequently measure in tight spaces or blind holes, a ball-type or specialized design might be more appropriate.
Maintenance and Calibration
Proper care is essential for maintaining the accuracy of your inside micrometer. Keep the measuring surfaces clean and free of debris. Apply a light coat of oil to prevent rust, especially for steel instruments. Regular calibration is vital to ensure continued accuracy. Compare your micrometer's readings against a known standard, such as gauge blocks or a certified calibration standard, and adjust as needed according to the manufacturer's instructions.
