Verdict T31 Imperial Dial Test Indicator – 1 3/8" Dial, 0.0005" Graduation, 0.04" Range

The Verdict T31 extends the measuring range of the T30 platform, offering twice the travel for setup and inspection tasks that demand more stylus movement in a familiar 1 3/8"/35 mm package.

Manufactured by Verdict Gauge Limited — Britain's leading dial test indicator maker, established in Kent in 1938 — the T31 Imperial (SKU T31I) combines a 1 3/8" dial face graduated in 0.0005" increments with a 0.04" total measuring range. Designed and made in Britain, every Verdict DTI is built around jewelled bearings, a patented pear-shaped stylus and a precision worm-spiral movement that eliminates cosine error, parallax error and irregular readings.

Key Features

• Dial face: 1 3/8" imperial dial for fast, glare-free reading at the bench or on the machine.
• Graduation: 0.0005" per division for confident, repeatable readings.
• Measuring range: 0.04" total travel suited to both fine alignment and broader inspection work.
• Dial reading: 0-20-0 balanced scale for direct plus/minus deviation readout.
• Stylus length: 1.622", with Verdict's patented pear-shaped contact for clean, friction-free engagement.
• Movement: precision worm-spiral mechanism running in jewelled bearings — smooth, shock-resistant and built to last.
• Switch lever: manually reverses the direction of stylus movement to suit either positive or negative feature inspection.
• Mounting: 4 mm / ¼" diameter top spigot, dovetail body, and holder side-clamp accepting rods up to 6.5 mm / 0.256" — compatible with the full range of standard DTI accessories, magnetic bases and indicator arms.
• Origin: designed and manufactured in Britain by Verdict Gauge Limited.

Specifications

Typical Applications

• Aligning vises, fixtures and workpieces on milling machines and machining centres.
• Checking concentricity, runout (TIR) and parallelism on lathes and grinders.
• Surface plate inspection and comparator-style measurement against masters.
• Tramming spindles and indicating bores, slots and machined features.
• In-process quality control and final inspection in toolrooms and calibration laboratories.

Backed by the exclusive Verdict guarantee, the T31 Imperial is supplied ready for use and is fully compatible with the wider Verdict accessory range as well as third-party dovetail clamps, swivel holders, magnetic bases and height-gauge attachments. Calibration and repair are available through Verdict's UK service centre using only genuine original spares.