Height gauges have emerged as an indispensable instrument within the realm of metrology. With a history spanning multiple industries, they have played a pivotal role in the performance of precision measurement, with manufacturers, engineers and quality control professionals relying on their accuracy.
This article provides insight into the different types of height gauges, including the timeless Vernier and the more modern digital counterpart. First, a quick introduction to precisely what a height gauge is.
What is a Height Gauge?
A height gauge is a precision measurement tool used to determine the vertical distance or height between two points. It consists of a vertical column mounted on a stable base, with a measuring spindle that holds a measuring instrument. Height gauges can be analogue or digital; they incorporate scales, such as a vernier scale or digital display, to provide accurate readings. They play a crucial role in maintaining quality standards and facilitating various machining and measurement tasks.
In keeping with the engineering/cost trade-off, various levels of capability and price are available. Further in this article, we explore some of their features. Before that, let’s quickly mention the different types of height gauges available.
Types of Height Gauges
Vernier height gauges are traditional gauges that utilise a vernier scale to achieve precise measurements. The main scale is graduated along the vertical axis, and a smaller vernier scale slides alongside it. Vernier height gauges are reliable and can provide measurements down to a few micrometres; however, they require careful interpretation and are more time-consuming than modern digital gauges.
Vernier height gauges find utility in various applications where precision measurements are crucial but where advanced features offered by digital technology might not be necessary. Their mechanical design makes them suitable for workshops, small-scale manufacturing and educational settings where they are often used for comparative measurements, layout marking and depth assessments.
Dial Height Gauges
Dial height gauges have a large circular dial with a pointer attached to a measuring spindle. As the spindle is moved up or down, the pointer rotates around the dial, indicating the height measurement. These gauges are easier to read than Vernier gauges, as they provide a direct analogue display of the measurement.
Dial height gauges offer a balance between traditional analogue readings and enhanced accuracy. They are commonly used in workshops and manufacturing environments for their simplicity and accuracy; their quick visual indication of measurement makes them efficient for tasks like machine tool alignment, depth measurements and part verification.
Digital height gauges incorporate digital technology to provide quick and precise measurements. They have a digital readout display that directly indicates the height measurement in a digital format, eliminating the need for manual interpretation. Users can easily switch between different measurement units and achieve higher accuracy without the risk of human error. Advanced models even have data output capabilities, allowing them to interface with computer systems for data logging and analysis.
Digital height gauges are the go-to choice for precision measurement, requiring high accuracy, repeatability and advanced features. They are commonly used in aerospace, automotive and electronics design industries where quality control, calibration, research and development, and rapid data output and analysis are paramount.
Besides the obvious, example uses of height gauges include measuring heights for quality control, machining setup, calibration reference, alignment, layout inspection, depth, flatness and parallelism.
Height Gauge Parts
The base of a height gauge provides the support and stability required for measurement. Typically made from a solid cast iron base, it may be placed on a flat granite surface plate for precise measurements. A column, or vertical beam(s), perpendicular to the base and usually made from metal, facilitates smooth and controlled vertical movement. An axis carriage is used to carry a measuring instrument such as jaws, scribes or probes to the workpiece being measured.
Characteristics and Properties of Height Gauges
Height gauges come in various sizes and scales to meet the requirements that span industries and applications. They can provide accurate measurements within specified tolerances (maintenance and calibration can help maintain this accuracy). Modern height gauges can have very fine resolutions with high repeatability. They can also measure at speed, contributing to improved productivity in manufacturing and inspection processes.
While all height gauges serve the same fundamental purpose of measuring height and dimensions, expensive models typically offer advantages in terms of accuracy, durability and additional functionalities.
Height gauge components must also be precise to provide exceptional accuracy and preciseness. Precision manufacturing such a gauge naturally incurs greater expense. To provide greater durability, comparatively more expensive materials will be used.
An example of an advanced digital height gauge is the Vertex VMS. It features comprehensive 1D and 2D measurement, has advanced movement and stability control, is motorised and will integrate with a computer.