Description
Product Overview
The Mitutoyo 511-128 Dial Bore Gauge covers a 50–100mm measuring range and represents the workhorse end of Mitutoyo’s bore gauge lineup — a tool that belongs on any serious toolroom bench. With a full set of interchangeable extension rods and washers, this kit gives you the reach to check bores from small hydraulic cylinder housings right through to large bearing housings, all with the repeatability and contact geometry that bore gauging demands. If you’re chasing consistent, reliable internal diameter readings without setting up a CMM, this is the class of tool that gets the job done.
- 50–100mm measuring range with interchangeable extension rods — The graduated rod set lets you step through the range in increments, keeping the measuring head geometry correct at each setting. This matters because a bore gauge used outside its rod’s designed reach will load the contact points incorrectly, introducing cosine error and killing your repeatability. Dial it in with the right rod and you’re reading true.
- Dial indicator with 0.01mm graduation — One-hundredth-of-a-millimetre resolution is the practical standard for bore work in a production or toolroom environment. You’re not splitting tenths here, but for checking fits to H7/h6 tolerances, verifying reamed bores, or comparing to a master ring, 0.01mm is entirely fit for purpose and readable at a glance without squinting at a vernier.
- Spring-loaded centralising head with replaceable anvils — The self-centring contact design rocks the gauge to find true diameter, which eliminates operator-to-operator variation in how the tool is presented to the bore. Worn or damaged contacts can be replaced without retiring the whole instrument — a practical advantage over fixed-anvil designs.
- Original Mitutoyo case with full extension rod set and washers — Every rod and washer is present, meaning the full 50–100mm range is accessible without hunting for missing components. The original foam-lined case protects the instrument and keeps the rod set organised — important when you’re pulling gauges in and out of a cabinet multiple times a day.
- Ideal for — Checking engine cylinder bores for wear and taper, verifying reamed and bored holes in jig and fixture work, inspecting bearing housing fits, confirming internal grinding results, incoming QC on castings and forgings, and setting up four-jaw or independent-chuck bores to a target diameter.
Condition
Used (Good Condition / Complete Kit, Fully Functional)
The bore gauge body and dial indicator are in good used condition. The measuring contacts and extension rod threads are intact with no visible damage to the seating faces. The dial indicator needle sweeps freely with no stiction or dead band observed, and the bezel and crystal are undamaged. The extension rods and washer set appear complete across the full range (50mm through 100mm in steps, plus 0.5mm, 1mm, 2mm, and 3mm washers visible in the case). As with any used bore gauge, we recommend zeroing the instrument against a certified master ring or a precision bore standard at your intended range before taking it into production measurement. This is standard practice regardless of tool history and will confirm the gauge is reading within your required tolerance. There are no missing components that would prevent full use across the stated range.
Included
- 1 x Mitutoyo 511-128 Dial Bore Gauge, 50–100mm, 0.01mm graduation
- 1 x Full set of interchangeable extension rods (50mm through 100mm in steps)
- 1 x Set of spacing washers (0.5mm, 1mm, 2mm, 3mm)
- 1 x Replacement contact anvil set
- 1 x Original Mitutoyo fitted carry case
- 1 x Original Mitutoyo instruction manual / papers
Not Included
- Setting / master ring gauge (required for zeroing — not included, sold separately)
Brand Information
Mitutoyo Corporation is a Japanese precision instrument manufacturer founded in 1934 and widely regarded as the global benchmark in hand-held metrology. Their gauges, micrometers, and indicators are the reference standard against which most other toolroom instruments are compared, sitting in the same tier as Mahr, Tesa, and Starrett for accuracy, finish quality, and long-term calibration stability. Japanese manufacture means tight process controls, consistent material specifications, and a global calibration and service network — factors that matter when a gauge needs to hold its certification across years of production use.
Specifications
| Feature | Specification |
|---|---|
| Brand | Mitutoyo |
| Model / Code No. | 511-128 |
| Type | Dial Bore Gauge (Cylinder / Internal Diameter Gauge) |
| Series | 511 — Dial Bore Gauge Series |
| Measuring Range | 50–100mm |
| Graduation / Resolution | 0.01mm |
| Dial Indicator Travel | ±0.5mm (comparative measurement against master setting) |
| Measurement Method | Comparative (zero against master ring or micrometer setting fixture) |
| Contact / Anvil Material | Carbide-tipped replaceable contacts |
| Extension Rods Included | 50mm, 55mm, 60mm, 65mm, 70mm, 75mm, 80mm, 85mm, 90mm, 95mm, 100mm |
| Spacing Washers Included | 0.5mm, 1mm, 2mm, 3mm |
| Country of Origin | Japan |
| Condition | Used — Good Condition, Complete Kit |
| Included Items | Bore gauge body, full extension rod set, spacing washers, replacement contacts, original case, instruction manual |
| Not Included | Setting / master ring gauge |
Keywords
Mitutoyo 511-128, Mitutoyo dial bore gauge, bore gauge 50-100mm, internal diameter gauge, cylinder bore gauge, bore mic, dial bore gauge toolroom, Mitutoyo bore gauge Australia, internal measuring gauge, engine cylinder gauge, precision bore measurement, toolroom metrology
