Pneumatic Sander: Features Of Straight And Eccentric, Hand And Collet Grinders. How To Choose The Best Metal Cutting Machine?

2024 Author: Beatrice Philips | [email protected]. Last modified: 2024-01-18 12:09

When a master needs a device that can remove excess material from a flat surface without scratching the base, he picks up a sander. This technique is in great demand, ensuring the quality of the final result and uniformity of processing. In the article, we will consider the characteristics of such equipment and outline the main criteria by which it is chosen.

Features and scope

Today, grinding machines are used not only for grinding - they polish work surfaces, they are used in construction, metal rolling, car repairs not only by individuals, but also by large enterprises. At the same time, a different type of material can be processed with this technique, including wood, metal, plastic. Pneumatic grinders level the bases well, they clean the metal from the rust that appeared as a result of the coating operation.

Grinding machines can work even on natural and artificial stone and glass . In addition to the basic functions, these units can be used for smoothing welds and preparing the painted surface for polishing. When polishing, the disc is replaced with a felt disc.

The equipment can be used in different conditions, including explosive and at remote sites where it is impossible to connect to the power supply.

Pneumatic units are preferred not only because of their explosion safety. In addition to the fact that the equipment is capable of working with hazardous dust in the atmosphere, it is electrically safe, which is especially convenient when working on a conveyor. In addition, air grinders can be operated continuously. This allows you to increase the efficiency of work and eliminate the forced downtime for its cooling.

The noise of pneumatic machines is stronger than electric analogs . Another difference from electrical equipment is their lower weight (about one and a half times), which is compensated by the greater weight of the hose.

The performance of pneumatic equipment is high, the machines are equipped with protection from the cold.

Types

Today, brands produce grinding products, which can be conditionally divided into several groups: straight, polishing, end and angular. Modifications differ in design features and speed. For example, angular PSHM differ in the perpendicular arrangement of the working shaft relative to the tool axis. In addition, they are distinguished by engine power and a maximum disk rotation speed of up to 22,000 rpm. You can cut different materials with them.

End modifications consist of a rotary air motor , a speed controller, a handle with a starting device and a glass that acts as a noise damper. A protective casing is installed in its lower part. The grinding disc is fixed to the output end of the rotor shaft.

Direct analogs differ in the parallel arrangement of the working shaft relative to the common axis of the tool. This nuance allows for greater precision when machining edges, corners and surfaces in small areas. Such equipment is used to perform delicate work.

Eccentric sanders have their own design features . In them, the disk moves in a circle and orbit. This nuance contributes to better surface treatment. Such equipment is used for both rough and fine work. For example, it is used to prepare cars for painting, as well as wood substrates.

Collet modifications can be straight and angular . They have a working pressure of 6.3 bar, weigh less than 1 kg, and an air flow rate of 200 l / min.

Such products are used for processing bases in hard-to-reach places. Collet machines can rotate at 14,000, 15,000 and 30,000 rpm.

Construction characteristics

Pneumatic hand tools are inherently powered by air. During operation, air is supplied, compressed by the compressor. The higher the air pressure, the higher the rotational speed of the disc. This technique weighs on average from 600 g to several kg. The lightness allows you to reduce hand fatigue and better handle the required surfaces.

Pneumatic grinders consist of several key components: housing, rotary motor, starter, centrifugal regulator, and protective cover. The basis of the product is a metal case. Due to its lightness and strength, it improves the convenience of the user, at the same time being the protection of working elements from accidental mechanical damage. An equally important element is the handle, on the convenience of which the distribution of the load on the hand and the efficiency of work depend.

The design includes an abrasive disc, which can differ in diameter, which directly affects the quality of processing and its execution time. The sole of pneumatic grinders is necessary for performing rotational movements. The noise level of the devices may vary depending on the type.

The eccentric versions are characterized by low compressed air consumption, which contributes to cost savings . Such structures are quite strong and durable, due to which the costs of their maintenance are reduced. The availability of special options allows for continuous dust removal, minimizing finishing operations as well as reducing costs. The quality of the grinding and its pattern are ensured by the precise movement of the eccentric.

Products can be equipped with the option of braking the sanding pad, due to which it is possible to reduce the number of errors at the beginning of work. Some models are characterized by low vibration levels. This not only simplifies the workflow, but is also less harmful to the operator's health.

Some modifications are equipped with a dust collector option.

How to choose?

When buying equipment for your own needs, you should pay attention to a number of nuances. It is important to "try on" it, which will allow you to understand the degree of convenience of the product in work and its duration without feeling tired. It is important to pay attention to the fact that the higher the speed per minute of the model, the thinner and better the processing. The speed of rotation of the abrasive disc must be matched to specific needs. Also important parameters when buying are:

• the option to adjust the speed of rotation of the disk;
• the presence of a dust collector;
• dimensions of pneumatic equipment;
• product weight.

The price will also be the determining factor: quality equipment is not cheap. As a rule, products of a higher price category are characterized by greater equipment capabilities.

In addition, you need to pay attention to the eccentric stroke. For example, if you need to prepare the surface for further application of primer or paint, as well as sand the surface for polishing, the travel of the machine should be 3 mm.

When choosing a product for wood or metal, you need to take into account the performance of the compressor . The machine requires at least 400 l / min. At the same time, we must not forget that in order to prevent air losses in the air duct, you will have to carefully select the diameter of the air duct. It is important to carefully select the disc diameter in relation to the type of work planned.

When looking after a product for metal, it is worth considering the following. If the machine is needed for cleaning welds and getting rid of burrs on metal substrates, you can take a closer look at the option with a turbine drive. Products of this type are characterized by low air consumption. Their motor can withstand many hours without being repaired. The modifications themselves consist of wear-resistant parts, they have a fast valve response under load and are distinguished by a low level of acoustic pressure.

Which are the best?

Among the variations with a turbo drive, the best products, according to buyers, are models from the Hoffmann Group. An excellent purchase option would be a typical pneumatic cut-off grinder. It sits well in the hand, has a hose instead of a power cord, which is connected to the pneumatic system (compressor). Among other modifications, several models can be noted that are also in demand among buyers.

• Concorde CD-DG260 - straight grinder for processing parts and seams with a capacity of 25,000 rpm. It has a collet size of 6 mm, weighs half a kilogram, is characterized by compactness and ergonomics.
• 7025RE Rodcraft - equipment of radial type with immersion in hard-to-reach places and with a productivity of 22,000 rpm, designed for work with hard surfaces.
• MIGHTY SEVEN QB-135 - corner modification with ergonomics and strength of the case. Great for working on metal surfaces. It has a power of 570 W and an air flow rate of 170 liters per minute.

• Caliber PMShU-6, 3 / 125PT - compact pneumatic grinding machine for metal, characterized by precision cutting and grinding, sheet fastening with Velcro and low consumption of compressed air.
• Wester Exs-20 - eccentric surface grinding model, characterized by high quality and efficiency of work. The design is characterized by the fastening of sanding sheets by means of clamps, and has rubber inserts that reduce the level of vibration.
• Makita BO5012 - a miniature device designed for small needs. Differs in light weight, has a dust collector, provides for speed control, has a start button lock.