Starrett Inside Hole Micrometers
Find the inside diameter of cylinders and rings. These micrometers have a plain thimble, which relies on operator feel for accurate measurements.
124 series have solid steel extensions that attach at one end of the micrometer head.
823 series have lightweight tubular extensions that can attach at either end of the micrometer head.
Collars (sold separately) extend a micrometer’s measuring range. Handles (sold separately) screw into a micrometer head to extends its reach for measuring deep holes.
| Measuring Range | Accuracy | Measuring Increments | Material | Number of Extension Rods | Extension Rod Dia. | Number of Heads | Head Travel | Includes | Manufacturer Model Number | Each | |
124 Series—Plain Thimble | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2"-8" | ±0.0001" | 0.001" | Steel | 6 | 1/4" | 1 | 1/2" | __ | 124AZ | 000000 | 0000000 |
| 2"-12" | ±0.0001" | 0.001" | Steel | 10 | 1/4" | 1 | 1/2" | __ | 124BZ | 000000 | 000000 |
| 2"-32" | ±0.0001" | 0.001" | Steel | 10 | 1/4", 11/32" | 2 | 1/2", 1" | __ | 124DZ | 000000 | 00000000 |
| 8"-32" | ±0.0001" | 0.001" | Steel | 4 | 11/32" | 1 | 1" | __ | 124CZ | 000000 | 000000 |
823 Series—Plain Thimble | |||||||||||
| 1.5"-8" | ±0.0001" | 0.001" | Steel | 5 | 3/8" | 1 | 1/2" | 5 1/2" Lg. Handle | 823AZ | 000000 | 000000 |
| 1.5"-12" | ±0.0001" | 0.001" | Steel | 8 | 3/8" | 1 | 1/2" | 5 1/2" Lg. Handle | 823BZ | 000000 | 000000 |
| 1.5"-32" | ±0.0001" | 0.001" | Steel | 10 | 3/8" | 2 | 1/2", 1" | 5 1/2" Lg. Handle | 823FZ | 000000 | 00000000 |
| 4"-24" | ±0.0001" | 0.001" | Steel | 7 | 3/8" | 1 | 1" | __ | 823CZ | 000000 | 000000 |
| 4"-32" | ±0.0001" | 0.001" | Steel | 8 | 3/8" | 1 | 1" | __ | 823DZ | 000000 | 000000 |
| 4"-40" | ±0.0001" | 0.001" | Steel | 10 | 3/8" | 1 | 1" | __ | 823EZ | 000000 | 000000 |
Inside Hole Micrometers for Grooves
Reach into bores to measure the precise size and location of grooves. These micrometers have two discs on their measuring spindle to find a groove’s edge. Slide the spindle into your bore, press the discs against the wall and into the groove, and twist the thimble to measure the distance between the two discs. A speeder knob moves the measuring spindle more quickly toward or away from your groove, without turning the thimble repeatedly. When the spindle touches the groove you’re measuring, it will stop tightening, but the speeder knob will continue turning with a clicking sound. The spindle doesn’t rotate, so the contact points won’t spin or slip out of a groove.
Measuring Range | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Inside | Outside | Accuracy | Measuring Increments | Material | Overall Lg. | Manufacturer | Manufacturer Model Number | Each | |
Ratchet-Stop Thimble—Nonrotating Spindle | |||||||||
| 0.055"-1.05" | 0"-1" | ±0.0004" | 0.001" | Steel | 9 1/2" | Mitutoyo | 146-232 | 0000000 | 0000000 |
| 1.05"-2.05" | 1"-2" | ±0.0004" | 0.001" | Steel | 9 1/2" | Mitutoyo | 146-233 | 0000000 | 000000 |
| 2.05"-3.05" | 2"-3" | ±0.0004" | 0.001" | Steel | 9 1/2" | Mitutoyo | 146-234 | 0000000 | 000000 |
| 3.05"-4.05" | 3"-4" | ±0.0004" | 0.001" | Steel | 9 1/2" | Mitutoyo | 146-235 | 0000000 | 000000 |
Economy Inside Hole Micrometers
Measure the inside diameter of cylinders and rings. These micrometers have a plain thimble that turns freely without friction or a stopping device. It relies on user feel for accurate measurements. All include steel extensions that you can attach to one end of the micrometer head.
Mitutoyo Electronic Inside Hole Micrometers
With an LCD screen, these micrometers make it easy to read inside diameter measurements taken from cylinders and rings. Place the micrometer inside your bore, then turn the thimble until the spindle makes contact with both sides. For an accurate reading, stop turning as soon as you feel resistance on the thimble.
USB data cables (sold separately) connect micrometers directly to your PC.
10-pin data cables (sold separately) connect micrometers to a Mitutoyo miniprocessor or multiplexer.
Wireless data transmitters and receivers (sold separately) let you send data from micrometers to your PC without a cable.
Measuring Range | Accuracy | Measuring Increments | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Inch | Metric | Inch | Metric | Inch | Metric | Material | Number of Extension Rods | Extension Rod Dia. | Number of Heads | Head Travel | Batteries Included | Manufacturer Model Number | Each | |
303 Series—Plain Thimble | ||||||||||||||
| 8"-40" | 204 mm-1,016 mm | ±0.0015" | ±0.040 mm | 0.0001" | 0.001 mm | Steel | 6 | 5/8" | 1 | 1" | Yes | 339-303 | 0000000 | 000000000 |
Mitutoyo Inside Hole Micrometers
Find the inside diameter of cylinders and rings. Rotate the plain thimble until it fits snugly inside the space you’re measuring. These micrometers rely on the operator to determine a secure fit to take accurate measurements. Attach one of the included extension rods to the micrometer head to measure in hard-to-reach spaces.