How to use the protractor and why is it needed? The protractor is a measuring instrument designed to measure angles during various construction and repair work. There are various models on sale, it is possible to choose a device that is most suitable for performing a particular type of work.
The device of a goniometer with the nonius.
What goniometer will do?
All models that are currently used for measuring work can be divided into 7 types. Everyone has their own characteristics, they have different specializations, their design also differs.
Construction goniometer device.
- Construction protractor is used for installation, design, marking works. Products vary in size, in the method of measuring angles. When laying the foundations used tacheometer - this is one of the varieties of optical equipment. If you need to perform installation work of a small volume, it is better to use a rake protractor, which has a length of approximately 50 cm.
- The metal protractor is designed specifically for delicate work, where high precision takes precedence.
- The carpentry model is approximate, it is used only when working with wooden structures.
- Mountain varieties are called surveyors, angles can be measured even at a distance, if the range is large. Many works require the use of just such equipment.
- Astronomical protractor is a special high-precision equipment, which is used only for a narrow range of work. Its accuracy is the highest, but the use of such a device is justified only for a small area of work.
- Nautical devices are used for calculations only on oceanic and sea spaces.
- Artillery protractors are designed for targeting. Use them only for specific cases.
By the principle of operation and design features, all proposed models can be divided into:
Control angles cutters goniometer.
- Electronic products, they are also called digital. These devices are accurate, work on the principle of semiconductors. On the front of the device there is a display, a reading is displayed on it. The tool is accurate, it allows you to perform even complex work with ease.
- Laser equipment operates on the principle of the direction of the beam to a point. The downside is that it’s difficult to see the laser pointer beam with the naked eye. For this, additional receivers are used to ensure accurate targeting.
- Optical goniometers have a special lens, which is used for measurement.
- Pendulum devices are designed to obtain accurate measurements. They are common in tool making, work on the principle of a pendulum. The scale remains fixed, only the arrow, which is placed on the counterweight, moves during use.
- Among the mechanical tools are nonius and ordinary models. The tool is compact, the contact with the planes is tight, as accurate as possible.
- The device of fixed angles makes it possible to determine the exact value, check the flatness. For example, it is used to check the angles at 90 or 30 degrees. It is rather a template than a full-fledged measuring tool.
How to use the protractor?
The design of the pendulum protractor.
The most convenient and familiar is the usual mechanical protractor, which many can use. Universal equipment of this type can be applied to almost any surface, taking readings is easy and convenient. It is possible to work not only with internal corners, but also with external ones. Mechanical goniometer can be traditional vernier or optical.
In the first case, the instrument has a special scale that allows to increase the accuracy of the values by an order of magnitude. Such tools for use are similar to a caliper, during operation usually does not arise difficulties. When planning a purchase, it is recommended to abandon cheap Chinese devices, since their accuracy does not correspond to the required one. Preference should be given only to proven manufacturers. Optical devices have a special magnifying glass, with which you can easily see the values on the bar. Using it is a little more difficult, but with a little practice, everything is solved simply.
Today, various types of automated devices are used, and the more devices are automated, the more convenient it is to handle them. It is only necessary to fix the desired position, after which the result will be displayed on the display. The optical device will require only a flat surface, since even the slightest deviations from the horizon will make the results incorrect, unsuitable for use.
Vernier devices are applied on the plane so that the body and ruler coincide with the sides of the corner.
In this case, it will be easy to read the readings. Degrees are displayed on the main scale. Outwardly, this is a normal protractor, well known to everyone since high school. It is convenient to use them, it is necessary to count the divisions from the zero point to the set point. You can calculate the value for the angle, if necessary. Nonius devices are simple, it is extremely easy to use them, their size is the most varied.
Optical movable protractors move during the calculation. It is necessary to fix a special ring of the clamping type, while the magnifier and the disc depend on the position on the ruler. They will be indicators of the value you want to get. Through a magnifying glass visible markup deposited on the disk. It is correlated with the mark that is on the plate, after which the reading of the device is determined.
Electronic goniometers are the most convenient options, but they are used mainly in construction. Get the most accurate dimensions, they are displayed on the display. It is enough to install the working legs of the instrument, after which the instrument will show the angle value. An electronic tool can even be used by a beginner without studying any instructions.
Using the protractor is simple. Special experience is not required, it is only necessary to choose the appropriate type of equipment, the most appropriate for the tasks. If calculations are rarely performed, it is better to use a conventional mechanical device. For quick measurement, it is better to use special automated products with a different set of functions.