Description
Product Overview
- 10–18 mm measuring range with 0.01 mm graduation — The 511-201 targets the range where small-bore work gets difficult. Needle bearings, valve guides, hydraulic spool bores, and small reamed holes all live in this band. A 0.01 mm dial increment lets you resolve fits and tolerances that a telescoping gauge will simply smear past.
- Self-centring rocking measurement method — The gauge head rocks on the anvil contact to find true minimum diameter, eliminating the operator-induced cosine error that plagues two-point telescoping gauge measurement. Repeatability is what gives you confidence, and Mitutoyo’s 511-series geometry is designed around it.
- Interchangeable contact tips and extension rods — The case includes a full set of numbered contact tips (No.1 through No.10, covering 10 mm to 18 mm in 1 mm steps) plus a 0.5 mm tip, allowing you to select the correct anvil protrusion for each target diameter. This means one gauge handles the full range without compromise.
- Compatibility and zeroing — The 511-201 is zeroed against a ring gauge or an outside micrometer set to the nominal bore diameter. No ring gauge is included; if you don’t already have one, a setting micrometer or a certified ring gauge will be required to put this instrument to work. The 511-series accepts standard Mitutoyo 511-series replacement tips.
- Ideal for — Checking needle and plain bearing bores, reamed and honed cylinder bores, hydraulic valve and spool body bores, press-fit housing inspection, and small-bore roundness checks during lathe or jig-boring work.
Condition
Used (Good Condition / Pre-owned, functional, minor shop wear)
The gauge handle and stem show the kind of light surface patina and handling marks you’d expect from a quality instrument that has seen bench use — nothing that affects grip, function, or accuracy. The dial face is legible and undamaged, with no cracked crystal, lifted bezel, or fogged lens visible. The contact tips and extension rods show no obvious deformation, galling, or damage to the precision-ground spherical contact surfaces, which is the critical point: worn or pitted contacts will destroy repeatability far faster than any cosmetic wear on the handle. The tip seating mechanism functions correctly. As with any pre-owned bore gauge, zeroing against a certified ring gauge or a calibrated outside micrometer before use is strongly recommended — this confirms the dial is tracking accurately and gives you a verified datum before you commit measurements. There is no information from the seller to suggest the instrument has been dropped, overloaded, or repaired.
Included
- 1 x Mitutoyo Bore Gauge, Model 511-201, 10–18.5mm range, 0.01 mm graduation
- Full set of interchangeable contact tips (No.1–No.10, 10 mm–18 mm, plus 0.5 mm tip)
- Original Mitutoyo orange moulded carry case with foam insert
Not Included
- Dial gauge.
- Setting ring gauge (required to zero the instrument — not included)
- Calibration certificate
Brand Information
Mitutoyo Corporation, founded in Japan in 1934, is the global benchmark in hand-held precision metrology — sitting at the top of the market alongside Mahr and Tesa, and a clear tier above general-purpose brands. Their 511-series dial bore gauges are standard equipment in Japanese and Australian toolrooms, automotive engine shops, and precision engineering facilities where traceability and long-term calibration stability matter. Japanese-manufactured Mitutoyo instruments are specified by OEM manufacturers, defence contractors, and metrology laboratories precisely because the tolerances on Mitutoyo’s own components are held to the same standard they ask of yours.
Specifications
| Feature | Specification |
|---|---|
| Brand | Mitutoyo |
| Model | 511-201 |
| Type | Dial Bore Gauge (Inside Diameter Gauge) |
| Series | 511 |
| Measuring Range | 10–18 mm |
| Graduation / Resolution | 0.01 mm |
| Dial Reading | ±0.05 mm (±50 divisions from zero) |
| Measuring Method | Self-centring rocking action, two-point contact |
| Contact Tips Included | No.1 (10 mm) through No.10 (18 mm) + 0.5 mm tip |
| Construction | Hardened steel contact tips, chrome-plated stem |
| Country of Origin | Japan |
| Condition | Used — Good Condition |
| Included Items | Body, full tip set (No.1–No.10 + 0.5 mm), original Mitutoyo case |
| Not Included | Setting ring gauge, calibration certificate |
Keywords
Mitutoyo 511-201, Mitutoyo dial bore gauge, bore gauge 10-18mm, inside diameter gauge, small bore gauge, dial bore gauge Australia, bore mic, toolroom gauge, Mitutoyo 511 series, precision bore measurement, hydraulic bore gauge, bearing bore inspection
