Let's get to know the Vernier caliper better with Dinamitek

Vernier Caliper (also known as Vernier Caliper) - Learn More with Dinamitek

Let's learn more about a precise and reliable measuring instrument, simple to use once you learn the reading method and affordable: the caliper .

Made of stainless steel to prevent corrosion, the calipers have a chrome or satin finish to avoid dazzling the user when reading the measurement.

With the caliper you can measure:

• the width of an object
• the distance between two flat faces in a concavity
• the depth of a furrow
• the depth of a hole, even a threaded one

The precision of the caliper, compared to the millimeter, can be:

• decimal
• twentieth
• fiftieth
• centesimal

The best known caliper model is the Vernier caliper .

The vernier caliper consists of a graduated rule divided into two parts, one movable and one fixed:

• fixed graduated rod, marked with millimetres, usually 20 cm long
• movable cursor with graduated vernier scale that indicates the precision of the caliper, called slider, equipped with a brake to avoid misreading the measurement
• lobster

The rods are fitted with appendices that serve as stops for the dimensions to be measured:

• two nozzles for external measurements of length or diameter, one in the fixed part and one in the mobile part,
• two nozzles for internal measurements of length or diameter, one in the fixed part and one in the mobile part
• an L tab for depth measurements.

To make it easier to measure smaller spaces, the tips are beveled at the ends. This way, you measure the inside of the circumference, not the chord between the two meeting points.

The shape of the jaws determines the type of measurement the caliper is suitable for. The outer jaws rest against the external walls of the object.

The internal beaks with knife-like appendages come into contact with two walls located inside the object.
A depth gauge is inserted against the bottom of a cavity, using a reference surface on the cavity's edge. Therefore, to measure the depth of cylinders or cone tips, a round-rod gauge is the best choice.

To understand how the vernier scale works, let's use the example of the decimal vernier, where the cursor is divided into 10 parts, so with the caliper closed, the zero of the vernier corresponds to the zero of the fixed scale. The vernier notch corresponding to 10 mm coincides with 9 mm, i.e., the ninth notch of the decimal caliper. In other words, within the 9 mm range there are 10 divisions of 0.9 mm each, with a sensitivity of 0.1 mm.

The same thing happens for the twentieth vernier and the fiftieth vernier:

• Vernier 20 : in the 19 mm range there are 20 divisions of 19/20 mm with a sensitivity of 0.05 mm (1/20 mm).
• Fiftieth vernier : in the 49 mm range there are 50 divisions of 49/50 mm with a sensitivity of 0.02 mm (1/50 mm).

The capacity of the caliber corresponds to its maximum opening.

To make reading easier, you can opt for the clock model, in which the moving nozzle indicates the whole part of the reading, with scanning in multiples of 10 mm, and the hand the remaining fraction, in millimetres and twentieths of a millimetre, or the more practical digital caliper.

Depending on the type of reading, the caliber is defined as :

• vernier : the reading scale is on the body, the fractions are read on the vernier

• dial : the reading scale is on the body, the fractions are read on the clock face placed on the cursor

• digital : it has no reading scale, the measurement is read directly on the electronic indicator placed on the slider

Vernier calipers are calibrated by directly measuring calibrated templates, then comparing the reading with the nominal size of the template. External calipers use parallel gauge blocks, while internal calipers use calibrated rings.

If you need a caliper, send a request to our measuring instruments expert by writing to info@dinamitek.com