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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.
Heavy-Duty - The Starrett Solid-Rod Inside Micrometer has insulated rods marked with length, adjustable for length and quick-reading figures.
Hardened and Ground Anvils - The micrometer is equipped with hardened and ground anvils, while the measuring rods are solid. It has an excellent service life and outstanding work performance.
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.
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.
Accurate Measurements - 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.
【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
【Smooth and constant spring tension】 The spring is equipped with a knurled locking knob and a knurled fixing area.
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.
Precision Tools - Our Starrett hand tools have been the standard for high quality dimensional measuring tools since 1880, manufactured with excellence and superior workmanship.
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.
The Standard for Excellence - Proudly made in the USA, Starrett combines over 140 years of American heritage and innovation with globally sourced materials to deliver exceptional quality tools and products.
Heavy-Duty - The Starrett Tubular Inside Micrometer has rigid and lightweight rods, quick reading figures and lock nut. 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.
The Standard for Excellence - Proudly made in the USA, Starrett combines over 140 years of American heritage and innovation with globally sourced materials to deliver exceptional quality tools and products.
Dial Bore Gauge allows for a measuring range of 2"-6", with an accuracy of 0.001”, ideal for precise measurement of deep and complex bores
Dial Bore Gauge features self-centering design for accurate and reliable cylinder bore measurements
Engine Hole Cylinder Gauge Measuring Tool Set adopts a two-point contact system to measure hole diameters and detect geometry abnormalities
Engine Hole Cylinder Gauge Measuring Tool boasts a high quality aluminum alloy body and an insulated grip for comfortable, safe and durable use, coming with an ABS storage case for easy organization and portability
NOTE: Before measuring, make sure that the dial indicator's pointer is set to zero
Last update on 2026-07-18 / 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.
Frequently Asked Questions
What is the difference between an inside micrometer and a caliper?
Inside micrometers typically offer higher precision and accuracy for internal measurements compared to calipers. While calipers are versatile for quick measurements, micrometers provide finer resolution and more repeatable results for critical dimensions.
What does the resolution of an inside micrometer mean?
Resolution refers to the smallest increment of measurement that the micrometer can display or detect. For example, a micrometer with a resolution of 0.0001 inches can measure down to ten-thousandths of an inch.
How do I ensure consistent measurements with an inside micrometer?
Using the ratchet stop or friction thimble is key to applying consistent measuring force. Ensure the anvil and spindle faces are clean and that the micrometer is properly zeroed before taking any measurements.
Can I use an inside micrometer to measure the depth of a hole?
Standard inside micrometers are not designed for depth measurements. Specialized depth micrometers are required for accurately measuring the depth of holes or recesses.
What is the typical accuracy of a good quality inside micrometer?
For professional-grade inside micrometers, you can expect accuracies in the range of u00b10.0001 to u00b10.0002 inches for common measurement ranges. Higher-end or specialized models may offer even greater precision.
How often should I calibrate my inside micrometer?
Calibration frequency depends on usage and the criticality of the measurements. For frequent or high-precision work, annual calibration is recommended. If the tool is dropped or shows signs of inaccuracy, recalibrate it immediately.
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