Description
Product Overview
Measuring blind bore depths, counterbore steps, and recessed shoulder depths accurately is one of those jobs that separates a properly equipped toolroom from a shop that’s guessing with a rule and a prayer. When you need to confirm a counterbore depth to a tenth, check a stepped recess on a lathe part, or verify a pocket depth on a milled component, a digital depth micrometer gives you repeatable, readable figures — no interpolating a vernier scale under poor lighting, no ambiguity. The Mitutoyo 329-511-30 is a digimatic depth mic with a 0–150 mm range via interchangeable rods, a flat reference base ground to a reliable datum, and a digital readout that eliminates the thimble-reading errors that creep in on a standard barrel-and-thimble instrument. This unit is in used fair condition — fully functional with the complete rod set and documentation, but the LCD shows cosmetic discolouration worth noting before you buy.
- Digital Digimatic readout at 0.001 mm resolution — eliminates thimble misreading and barrel parallax errors that plague analogue depth mics, particularly useful when you’re taking multiple repeat measurements on a production run and need consistent figures logged or compared.
- 0–150 mm depth range via interchangeable extension rods — a single head covers shallow counterbores right through to deep bores and pockets by swapping rods, meaning you’re not reaching for a second instrument mid-job. The rod set in this kit gives you that full range in staged increments.
- Hardened and ground flat reference base — the wide base spans the bore or slot opening and references from a flat datum, which is critical for accuracy; a narrow reference will rock on a chamfered edge and give you a false reading. Mitutoyo machines these bases to a high flatness standard.
- Ratchet stop thimble — applies consistent measuring force on every contact, removing the variable of operator feel and keeping readings repeatable between users or across a shift.
- Ideal for: confirming counterbore and countersink depths on milled components, checking pocket depth on a machining centre setup, verifying shoulder and step depths on turned parts, inspecting blind tapped hole depths, and incoming inspection of cast or machined housings.
Condition
Used (Fair Condition / Functional with cosmetic LCD discolouration)
The mechanical side of this instrument presents well — the thimble rotates smoothly, the ratchet stop engages correctly, and the reference base shows no visible damage, gouging, or burring on the ground measuring surface. The interchangeable rod set is present and complete, and the rods show no visible bending or tip damage. The digital display is functional and reads, however there is noticeable discolouration on the LCD screen — this is a cosmetic issue, likely moisture ingress or age-related degradation of the display backing, and does not affect the numerical output or the instrument’s ability to take measurements. The digits remain legible. That said, any buyer intending to use this instrument for formal inspection or quality sign-off work should verify zero against a known flat reference surface and check repeatability against a setting standard or ring gauge before putting it into service. For shop-floor depth checking, prototype work, toolmaking, and general machining tasks, this instrument is fit for purpose as presented.
Included:
- 1 x Mitutoyo Digital Depth Micrometer 329-511-30 (0–150 mm, 0.001 mm resolution)
- Full interchangeable extension rod set
- Original Mitutoyo carry case
- Mitutoyo warranty / guarantee certificate (保証書)
- Original instruction manual
- Calibration certificate / documentation
- Spare battery / accessories pouch (as visible in packaging)
Not included: No setting standard or reference block included — recommend verifying zero on a known flat surface prior to use.
Brand Information
Mitutoyo is Japan’s largest precision measuring instrument manufacturer and sits at the top tier of the global metrology market alongside Mahr, Tesa, and Starrett — instruments trusted in aerospace, automotive, and defence manufacturing where tolerance stack-up is not a grey area. Founded in 1934 and headquartered in Kawasaki, Japan, Mitutoyo manufactures its own gauging, optical comparators, CMMs, and hand tools to exacting internal standards, with a worldwide calibration and service network. In the Australian toolroom, Mitutoyo is the benchmark brand — when a machinist says “grab the Mitutoyo,” everyone in the shop knows exactly what level of quality is expected.
Specifications
| Feature | Specification |
|---|---|
| Brand | Mitutoyo |
| Model | 329-511-30 |
| Type | Digital Depth Micrometer (Digimatic) |
| Series | Series 329 |
| Measuring Range | 0–150 mm (via interchangeable extension rods) |
| Resolution | 0.001 mm |
| Accuracy | ±0.004 mm (refer to Mitutoyo specification sheet for full range breakdown) |
| Display | LCD Digital (Digimatic) |
| Base / Reference | Hardened and ground flat reference base |
| Measuring Force | Controlled via ratchet stop thimble |
| Construction | Hardened stainless steel spindle and rods, precision ground base |
| Country of Origin | Japan |
| Condition | Used (Fair) — functional, LCD cosmetic discolouration present |
| Included Items | Depth micrometer head, full interchangeable rod set, original case, warranty certificate, instruction manual, calibration documentation |
| Not Included | Setting standard / reference block |
Keywords
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