Vernier Caliper, Stainless Steel

Quick Answer: The Vernier Caliper, Stainless Steel is a manual sliding caliper made from stainless steel, with a main scale on the beam, a vernier scale on the moving jaw, and jaws and a depth rod for outside, inside and depth readings. A stainless steel vernier caliper suits both physics practicals and workshop measuring.

Why the Metal Body Matters

Accuracy on any caliper depends on the two measuring faces staying flat and parallel. Stainless steel is hard enough for the faces and the knife-edged inside jaws to keep their shape through years of student use, whereas plastic jaws gradually round off. Graduations engraved or etched into a metal beam also stay legible after repeated cleaning.

Stainless steel resists rusting from sweaty hands and damp storerooms far better than plain carbon steel, which is why it is the usual material for workshop calipers. It is not immune: left wet, or kept near acid fumes in a chemistry preparation room, it can still stain. It also conducts electricity, so the plastic vernier caliper is preferred where a caliper will be used near live circuits.

Metal expands as it warms, but when a steel caliper measures steel parts at room temperature the two expand by similar amounts. Holding the beam in a warm hand for a long time before measuring a small object can shift a fine reading slightly, so take readings promptly and hold the caliper by the beam rather than the jaws.

Applications

• Measuring rod diameters and slab thicknesses for density and thermal expansion experiments
• Checking the bore of glass tubing so the right stopper or connector can be chosen
• Measuring filed and turned parts in fitting and machining workshops
• Taking the internal diameter and depth of a calorimeter for heat-capacity calculations

Specifications

Care & Handling

• Dry the caliper after use, especially after handling wet or oily parts, and keep it in its case.
• Store it away from the chemical store and fume cupboard, where acid vapour can spot even stainless steel.
• A thin film of light instrument oil on the beam keeps the slider running smoothly; wipe off any excess.
• Keep the depth rod and jaw tips for measuring only; scratching lines with them wears the faces.

Why Choose LabEquip

Institutes that want calipers to last through many student batches, and workshops that measure metal parts every day, generally choose stainless steel. LabEquip includes this model in the General Lab Products range; let us know the quantity and range you need via the contact page.

Frequently Asked Questions

Is a stainless steel caliper rust-proof?

It is rust-resistant, not rust-proof. Stainless steel copes with handling and humidity far better than plain steel, but it can still stain if left wet or exposed to acid fumes. Wiping it dry after use keeps it in good condition.

How is it different from a plastic caliper?

The steel beam and jaws are stiffer and harder, so they keep flat, parallel faces and fine graduations for longer, and finer least counts are usually offered on metal models. Plastic calipers are lighter, non-conducting and suit younger students.

Can I measure a part straight after machining?

Let it cool to room temperature first. A warm part is slightly larger than it will be when cool, so the reading will not match the drawing, and heat passing into the jaws can also shift a fine reading.

Is it attracted to magnets?

Some stainless steel grades used for tools are magnetic and some are not. If the caliper will be used near magnets or in magnetism experiments, test it with a magnet first, or use a plastic caliper for that work.

How can I tell if the jaws are worn?

Close the jaws and hold them up to a light. If light shows between the outside measuring faces, or the zero no longer lines up, the faces are worn or the slider is loose, and the caliper should be adjusted or kept for rough work only.

Can it be used for marking out?

It should not be used as a marking gauge. Scratching lines with the jaw tips blunts and wears the measuring faces. Use a scriber with a steel rule or a height gauge for marking out, and keep the caliper for measuring.

Last Updated: September 2026