Description
Product Overview
The Mitutoyo 102-230 is a 0–25mm outside micrometer built to JIS B 7502 standard — the same instrument you’ll find on toolroom benches across Japan’s precision manufacturing sector. With a 0.001mm graduation on a vernier-equipped thimble, this is a proper measuring instrument for work where “close enough” isn’t a phrase you use. Whether you’re checking turned stock diameter, verifying ground shafts, or confirming gauge block stack dimensions, this mic reads true and holds its zero the way a Mitutoyo should.
- 0.001mm vernier graduation — The thimble carries 0.01mm divisions and the vernier sleeve resolves down to 0.001mm (one micron), letting you interpolate to a single thou with confidence. That extra decimal place matters when you’re sneaking up on a press fit or checking a bearing journal tolerance.
- 0–25mm measuring range — Covers the bread-and-butter range for small-diameter turned work: bar stock, pins, shafts, and drill blanks. The anvil and spindle faces are carbide-tipped and lapped flat, so you’re measuring against ground reference surfaces, not soft steel.
- JIS B 7502 construction — The frame is a one-piece steel casting, hardened and stabilised. The barrel and thimble are ground to JIS tolerances for consistent feel across the full travel — no tight spots, no slop. The ratchet stop delivers repeatable measuring force so operator variation doesn’t creep into your readings.
- Ratchet stop and lock nut included — The ratchet stop ensures consistent spindle pressure shot to shot, critical when you’re measuring a run of parts and can’t afford to introduce feel-based variation. The lock nut holds the reading secure when you’re transferring to a height gauge or checking under a loupe.
- Ideal for — Checking turned shaft diameters for bearing fits, verifying drill and reamer blank stock sizes, measuring ground pin gauges, confirming stock removal on a cylindrical grinder, and inspecting small workpiece dimensions on a manual or CNC lathe.
Condition
(Used — Good Condition / Stored in non-original case, mechanically sound)
The mic is in good used condition and functions correctly across its full 0–25mm travel. The spindle advances and retracts smoothly with no binding, the thimble shows no detectable backlash, and the ratchet stop engages cleanly and consistently. Anvil and spindle faces appear free from pitting, scoring, or measurable wear — both critical surfaces look serviceable for accurate measurement. The seller notes the instrument has been stored in a different box to the one it shipped with (the case present is a compatible Mitutoyo-style plastic clam shell, not the serialised original), which has no bearing whatsoever on measuring accuracy. There is likely some light surface patina on the frame and thimble consistent with bench storage — cosmetic only. As with any used precision instrument, we recommend a zero check against a certified gauge block or setting standard before putting it to work in a critical application. If your work runs to tight tolerances, a quick verification against a 25mm gauge block or ring will confirm the instrument is reading spot-on and give you full confidence in the calibration.
Included:
- 1 x Mitutoyo 102-230 Outside Micrometer, 0–25mm, 0.001mm graduation
- 1 x Plastic storage / carry case (Mitutoyo-style, not the serialised original case)
- 1 x Original papers / instruction manual (Japanese / English, as pictured)
- 1 x Spanner / C-wrench (original accessory for barrel adjustment)
Not included: Serialised original box (instrument stored in a different compatible case as noted by seller). No setting standard or calibration certificate included.
Brand Information
Mitutoyo Corporation, founded in Japan in 1934, is the largest precision measuring instrument manufacturer in the world and the benchmark against which every other metrology brand is measured — literally and figuratively. Their outside micrometers are manufactured to JIS B 7502 and widely accepted as the industry standard in toolrooms across Australia, Japan, Europe, and North America, sitting clearly above mid-market brands and in direct competition with Mahr and Starrett at the top of the mechanical metrology tier. When you pick up a Mitutoyo mic, you’re handling an instrument engineered and manufactured in Japan to tolerances that the company’s own gauge blocks were designed to verify.
Specifications
| Feature | Specification |
|---|---|
| Brand | Mitutoyo |
| Model | 102-230 |
| Type | Outside Micrometer (Standard / Vernier) |
| Standard | JIS B 7502 |
| Measuring Range | 0–25mm |
| Graduation / Resolution | 0.001mm (vernier thimble) |
| Thimble Graduation | 0.01mm |
| Accuracy | ±0.002mm (per JIS B 7502) |
| Anvil / Spindle Faces | Carbide-tipped, lapped flat |
| Frame Material | Hardened steel, one-piece casting |
| Measuring Force | Controlled via ratchet stop |
| Lock | Barrel lock nut |
| Country of Origin | Japan |
| Condition | Used — Good Condition |
| Included Items | Micrometer, carry case, instruction manual/papers, spanner wrench |
| Not Included | Original serialised box, calibration certificate, setting standard |
Keywords
Mitutoyo 102-230, Mitutoyo outside micrometer, Mitutoyo 0-25mm micrometer, 0.001mm micrometer, JIS micrometer 25mm, vernier micrometer Australia, outside mic toolroom, precision micrometer machinist, bore mic bench micrometer, lathe inspection micrometer, used Mitutoyo micrometer, micrometer 0-25mm Australia
