Most craftsmen and processing specialists different materials For fine work, electric engravers and drills are used, which are more commonly called simply Dremel. They must exactly correspond to the purpose of use, which means it is time to consider the differences and features of choosing such a tool for your workshop or small home tasks.

What work is planned to be done

In our educational program we will give answers to most popular questions regarding hand drills and engravers. The most important of them is what determines such a variety of instruments and what is the specialization of individual varieties. The first thing a novice engraver or micromachining enthusiast needs to understand is that a drill is not universal tool. Before purchasing it, you need to know exactly what operations will be carried out during the work, and what specific materials will be processed.

Three most important criteria for any drill - power consumption, speed range and torque. Power - very relative concept, the real performance of the working body of the drill depends both on the efficiency of the engine and on the efficiency of the speed control system. However, it is by power that one can quite accurately determine the suitability of a drill for processing parts of various sizes:

• For engraving and invoicing - up to 50-70 W.
• For artistic carving - 100-150 W.
• For cutting and grinding small parts— 100-250 W.
• For multidisciplinary work with massive parts - from 200 W.

The ratio of spindle speed and torque is determined solely by the properties of the materials being processed. Thus, for milling plastic and tough metals, low speeds with high torque of 3.5-5 N/cm are required. In turn, stone carving, bone carving and grinding require a rotation speed of at least 35-40 thousand rpm, and torque is a secondary parameter that determines the amount of material removed in one pass. All these nuances will be discussed during our review.

A few words about Dremels

Drills are often mistakenly called Dremels, although this is only one of the brands. More knowledgeable people are asking the question: are expensive branded tools of this class really worth the money spent and is such a purchase justified if you have no experience of use?

Those interested should know that a limited number of power tools are produced under the Dremel brand, and these are mainly rotary hand drills. Their range is quite large - a dozen models of varying power with different ratios of spindle speed to torque. As a rule, branded tools are purchased not for one-time work, but with the expectation that they will pay off over time. professional activity. For beginners, Dremel or Proxxon drills can also be a profitable purchase; this tool has a significant margin of reliability and is quite tolerant of errors when choosing processing modes. In addition, the branded tool does not have such diseases as inaccurate collet fit, problems with cooling, alignment and engine balancing. However, buying a branded drill will be an adequate solution only if the instrument will be used more or less regularly, and not just as a test.

But what about other types of drills? In total, at least five can be distinguished:

1. Manual rotary drills.
2. Drills with a micromotor.
3. Hanging drills.
4. Pneumatic drills.

If, in the course of studying the material below, you come to the conclusion that it is ideal for your purposes certain type tool, it is better not to focus on a specific manufacturer. Having compared the processing features of certain materials and working conditions, it is necessary to establish exact specifications equipment, and only after that think about the issue of quality and reliability.

Nuances of processing different materials

Processing of materials using drills and engravers is carried out either by cutting, that is, milling, or by abrasive grinding. A special processing mode is implemented in engravers; they are essentially micro-perforators, that is, they process the material with a high-frequency impact method. And if when working with an engraver, the processing mode is determined mainly by the force of pressure on the tool, then the efficiency of cutting and grinding with a drill depends on the speed and torque.

Working with burrs requires maximum precision and the right choice cutting mode. As the radial distance of the cutting edges from the spindle axis increases, the angular velocity increases; accordingly, it is necessary to reduce the spindle speed. Rotation speed cutting tool should be high enough to effectively reject chips, but not too high so that the edges have time to cut portions of the material and do not rub against the surface to no avail.

You also need to take into account the viscosity, fusibility and hardness of materials. Almost no type of milling equipment is designed to operate at speeds above 30-35 thousand rpm, and at extreme speeds, needle cutters are mainly used. The maximum speed indicated above is determined for hard metals such as steel and stone, but for fluoroplastic or polyethylene this level is reduced to 4-6 thousand rpm; at higher speeds the chips simply melt. Working with burrs requires fairly accurate and smooth speed adjustment, which allows you to adjust the cutting mode on waste samples of material.

Abrasive grinding, on the contrary, is designed for high rotation speeds, which contributes to better cooling work surface And effective removal removed microchips. For this mode, drills capable of delivering 50 thousand revolutions or more are optimally suited. Torque for this type of processing is not of fundamental importance, because grinding and polishing are the final types of processing, where the material removal is absolutely negligible. A separate position from grinding and milling is occupied by the work of diamond burrs, which require the highest possible spindle speed - from 100 thousand revolutions per minute.

Engine type and location

The classic type of hand drill has a monoblock design. The housing houses a commutator motor; its armature shaft simultaneously serves as a spindle, at the end of which there is a collet for attaching equipment. At the back of the case there is simplest scheme speed control, the principle of which is to change the applied voltage. The advantages of this arrangement include high accuracy, simplicity and reliability, the disadvantages are a significant increase in the mass of the tool with an increase in power.

Direct rotary engraver device

Drills with a micromotor have a separate power supply, while the electric motor is located in the handle, and the power supply is in a separate housing. This arrangement provides higher ergonomics due to reduced weight and ease of control of the drill using a pedal. Another advantage of micromotors is the ability to use more effective schemes power supplies and speed control, with large overall dimensions and requiring active cooling of components. As a micromotor, either a conventional brushed DC motor or a brushless one, designed for more precise speed control, can be used.

Drill "Profile B-05" with power supply "Profile-6T"

A special type of drill with a separate motor is suspended; they are designed to connect the spindle to the handpiece via a flexible shaft. The main advantage of such drills is their virtually non-existent power limit. You can also point out the possibility of attaching a wide range of tips to the shaft, which themselves are quite cheap. In addition to rotary handles, impact engraving handles can also be used, designed for installing a gravel or chisel for wood carving.

Pneumatic drills have the same advantages due to their layout, but their handpieces are more expensive and are designed for use at extremely high rotation speeds - more than 300 thousand rpm.

Mains or battery

A standard benefit of battery power is the ability to work without being connected to a power source. electrical network. This advantage is especially pronounced when working in hard-to-reach places or on non-electrified objects. The disadvantages are also obvious - the operating time is limited by the battery charge and the limited service life of the battery itself.

However, in the context of operating a drill, battery power can have an additional benefit. For example, when processing bone, some types of plastics and glass composites, grinding and wet milling are required. The degree of protection of a power tool does not allow processing material with a coolant supply, but in the case of working with a cordless tool, at least the possibility of electrical injury is eliminated.

We would like to separately mention the disadvantage of battery-powered drills, such as the increase in weight, which is even more pronounced in comparison with networked ones. hand tools. We can talk about any ease of working with such a drill with a power consumption of up to 70-100 W; a more productive tool cannot be used for a long time - the hand simply gets tired and numb.

Ergonomics and controls

When choosing a drill, the ease of grip of the body and the absence of vibration are especially important. If everything is relatively clear with the first factor - it’s enough just to hold the tool in your hands and try it out before buying, then getting rid of vibration entirely depends on the design and layout of the motor with the spindle. If it is not possible to evaluate ergonomics, as is the case when ordering from online stores, you should pay attention to the quality of casting, the shape of the case and the presence of rubber pads that prevent slipping.

Vibration of the drill is categorically unacceptable, because even with the slightest trembling, after 3-5 minutes of work, a painful itch appears in the hands, and irreversible damage to the carpal and phalangeal joints occurs. Vibration in drills appears as a consequence of resonance, which occurs due to the transmission of vibrations from the working body to the engine and vice versa. The main reason for this phenomenon is poor alignment of the armature, the presence of a poor-quality intermediate kinematic transmission unit, or excessively rigid mounting of the engine. It is optimal if the commutator motor armature is mounted in shock-absorbing cups and the spindle is secured with a backlash-free needle bearing. For DC motors best way fastenings - fitting the motor housing into neoprene segment covers, as is done in Dremel drills. Also, an original technical solution was used in tools of the Profile brand - connecting the spindle to the motor with a damper coupling.

The quality of speed control depends on the design and type of engine. Corded hand drills use resistive or electronic circuit changes in the applied voltage, captivating with its cheapness and simplicity; the same control principle is implemented in most budget drills with a micromotor. The disadvantage of this scheme is a significant drop in torque by low revs and low adjustment accuracy. At the same time, high-quality suspended drills and micromotors use PWM control, which does not have the described disadvantages.

Engraving is one of the oldest methods of decoration. People carved designs to decorate their homes and tools, and the work of skilled craftsmen was always in value. Today this craft can become available to everyone thanks to an electric engraver or mini drill. Engravers can be used to make designs on various materials, manufacturing jewelry, modeling and all kinds of small work: drilling, stripping, polishing. These tools have a wide range of applications due to a large number nozzles

Device

The engraver resembles a drill or grinder, consists of a housing with a motor and a movable shaft with a mount for a working attachment. Please note that the collet (chuck for clamping equipment) can have a different diameter and is only suitable for attachments with a certain shank size. The most common size is 3.2 mm, but collets for engravers with a diameter of 1 to 4 mm are also available. The chuck can be quick-release or screw-type, requiring a key for fastening. The key one is more reliable, can withstand heavy loads, and the quick-clamping one reduces the time for changing attachments.
There are impact and rotary type engravers, they differ in the mechanism of operation. Impact hammers function like a mini hammer drill and are only suitable for engraving, while rotary hammers are a more versatile tool, allowing you to grind, drill and cut. Engravers are also distinguished by type of power supply; there are mains and battery-powered ones. Like other tools, corded models provide greater power and battery-powered mobility. More expensive engraver models are equipped with a shaft rotation speed controller. It can be electronic with fine tuning or simple mechanical, limiting the motor voltage. Impacts allow you to adjust the depth of travel of the nozzle.

Characteristics

• Shaft rotation speed. This is the main characteristic of the engraver. It is higher than other power tools and can be from 15 to 35 thousand revolutions per minute. To work with soft materials(wood, plastic, copper) and polishing will not require high speeds, and for dense products made of stone or steel, you should use a tool with at least 30 thousand revolutions per minute. For impact engravers, the corresponding characteristic is the number of strokes per minute, which can reach 6000.
• Engine power. Another important parameter, which directly affects the performance of the tool. Measured in watts (W), there are devices from 35 to 300 W. Please note that the price depends on the power, so if you do not plan to use it professionally, then it is quite possible to purchase a low-power entry-level engraver. For long-term work, especially with hard materials, you should take an engraver with a power of 200-300 W.

Engraver attachments

Nozzles (cones) are sold individually or in sets, from small ones of five or six pieces to universal sets that include one hundred or more items. The equipment differs in shape (cylindrical, disk, spherical, conical), purpose and material from which it is made. There are a huge variety of attachments for various purposes; they can be roughly divided into two groups:

• Carving and grinding. For cutting, milling and grinding hard metal and stone, nozzles coated with industrial diamonds or aluminum oxide are usually used; for soft products made of wood, glass and ceramics, silicon carbide abrasive is used.
• Polishing and cleaning. For polishing, you can use vulcanite nozzles or rubber ones with an abrasive coating. Felt and felt attachments are used with a special polishing paste, which consists of paraffin and sanding powder of different grain sizes. Various brushes are used for cleaning; for example, a metal brush can remove rust, paint, or create scuffs for an antique effect.

Choice

It is worth deciding in advance what materials you will be working with, why and how often you will use the tool, this will greatly facilitate the choice of model. You shouldn't be limited by what's included; most likely you'll use a limited number of attachments. Therefore it is better to take good tool with the basic set. Consumables you will still have to purchase it sooner or later, especially if you are constantly using it for some specific tasks. When choosing, pay attention to the ergonomics, dimensions and weight of the device. Working with an uncomfortable engraver will make you tired faster. The weight of such devices can be from 500 grams to 2.5 kilograms. Besides, important indicators, especially during prolonged operation, are noise levels and heat generation. Low-power devices do not heat up or make much noise, and professional engravers usually equip them with a cooler. Some devices come with a flexible shaft, a device similar to an extension for rotary engravers, which increases maneuverability and significantly improves convenience. The flexible shaft tip is thinner than the tool, which is better for fine and precise work. When using it, the engraver should be mounted, for example, on a special stand. For work you should choose a powerful one professional tool from manufacturers such as Dremel, Proxxon, Foredom, and for hobbies a household model from the brands Bort, Einhell, Hammer, Skil, Sturm and others is suitable. Follow safety precautions and do not neglect protective equipment. Fine dust and chips fly around during operation, so be sure to wear goggles and a mask.

A mini drill is an electric tool that is often used by amateur radio enthusiasts for various purposes. However, this device can be successfully used to perform other tasks in everyday life. Using this tool, you can drill various holes and cut many materials (plexiglass, plastic, wood, metal).

It is used for surface cleaning, milling, engraving, and sharpening. Using a mini drill, you can perform sanding, trimming and many other operations.

The device can operate both from an electrical network with a voltage of 220 V, and from a battery with a voltage of 12, 24, 36 V. Most often, the mini-drill includes a wide variety of interchangeable tools that can be inserted into a jaw or collet chuck. These additions include drills, various sizes and forms of grinding abrasive, cutting, polishing carved discs. In addition, the package may include grinding drums, polishing stones and felts, sharpening discs, wire brushes, burrs and other elements.

If necessary, you can make it yourself. You just need to attach the working part of the device to a metal rod, which can then be inserted into a collet or chuck. To do this, drill a hole in the middle of the nozzle or glue it to the surface of another suitable device available in the master’s arsenal.

Application makes it possible to hold only the working body, with the help of which various tasks are performed.

The mini-drill is equipped either with a set of replaceable collets into which the attachments are clamped, or with a miniature cam chuck that serves the same purpose. The latter is much more convenient because it allows you to use various diameters nozzles with shanks.

Many craftsmen manage to make a mini-drill with their own hands. To do this, they use a miniature electric motor left over from an old household appliances, for example, from or a tape recorder. In this case, it is important to be able to secure a cartridge or collet to the drive shaft. This mechanism is absolutely easy to make if you have at your disposal

However homemade devices not as convenient and practical as industrially manufactured devices.

Today you can buy a mini-drill from many well-known companies, and this tool is not that expensive. At the same time it is very convenient and reliable. On modern market electrical appliances, the leading position in the production of mini drills is occupied by Dremel, which is a subsidiary of the company

By the way, because of the name of the manufacturer, this tool is often called a “Dremel”. Prices for it depend on the configuration and power. A simple mini drill will cost about one and a half thousand Russian rubles. But quite good functional model You can buy it for three to four thousand rubles.

What is the difference between an engraver and a mini drill?

A mini drill is a tool that every craftsman needs. With its help, you can carry out operations in hard-to-reach places where use conventional drill impossible or impractical. The mini drill is designed for processing a wide range of materials: wood, plastic, ceramics, glass, precious materials and steel.

Essentially, an engraver is the same mini drill, but with a different attachment. The basis of the device is a straight grinder. But unlike a conventional angle grinder, or “grinder”, the engraver has a higher spindle speed: 10-35 thousand revolutions per minute versus 8-8.5 thousand.

The variety of work operations performed with an engraver (mini-drill) is explained by the wide range of attachments used. So the question of whether to buy an engraver or a mini drill does not make sense: buy different attachments - they will give you the opportunity to do more work.

For example, when choosing power tools in Bryansk, with us you can select the cutting wheels, drills, polishing and grinding attachments, files, cutters, brushes, cutting attachments.

Using an engraver you can do:

drilling holes different diameters in the materials listed above;

engraving and milling;

cutting and grinding;

cleaning and fine finishing;

sharpening and applying inscriptions and patterns.

The advantages of a mini drill are its light weight and small dimensions. The tool holding device is based on a standard collet clamp.

When buying an engraver in Bryansk, be sure to buy such a thing as a flexible shaft: it will help you do work even in hard-to-reach places. The delivery set includes a stand for hanging the mini drill along with the flexible shaft. The stand will make your work more convenient, reduce vibration and noise.