Part 1: Basics of Use

Once upon a time, in a dim corner of the college studio where I took my first jewelry lessons in working with metal, there was a rusty, bent drill, with a vacuum cleaner suspended from it to collect sawdust - and a barely flexible shaft with a toothed tip. We used this shaft to drill tiny holes into something.

The occasional attempt by the most daring students to do something more sophisticated usually ended badly. However, I was fascinated by the potential I saw in this tool.

It is often misunderstood and not enough attention is paid to the fact that the drill is one of the most universal tools at the master's studio. It can speed up and improve the manufacturing process of a product, “opening” the door to new possibilities for reworking, sanding and polishing. Using a drill, you can peel and grind stone, glass, metal, wood, and plastic, you can improve the finishing of castings, make wax models, and even use it as a hammer and lathe.

The abundance of many tips and fastening possibilities further expand the limitless possibilities of this tool. In this series of articles I will show how a drill can be more than just a drill!

Dremel or regular drill?

The names “Kleenex,” “Dremel” are often used as generic terms. Dremel rotary tools are manufactured by Robert Bosch Tool Corporation, but we tend to associate “Dremel” with any lower-priced portable rotary tool that contains a motor in the tip.

Because of its low cost, many people start with Dremel. But because the vibration motor is held in the hand, Dremel tools can't really perform the finer maneuvers that flex shafts can. Dremel variable speed drills can reach up to 35,000 rpm and are typically controlled via a dial, either on the tool itself or on a separate control unit. Most often these tools use a collet clamping system (typically 1.8 inch/3 mm) to clamp the drill bit, but this limits the range of tip sizes.

There are foot pedals for speed control and even flexible shaft mounts available for sale with Dremel, which do not make it possible to change the handpieces for these drills, and at the same time they simply do not provide the accuracy and versatility that an average-priced drill does.

Which brand should you choose? What model?

As with many tools, the first thing to do is decide what kind of work—and how much of it—you'll want the drill to do. For an amateur jeweler who produces a small number of items, for whom it is a hobby or a part-time job as an artist-engraver, a simple, basic drill with a lightweight engine will be sufficient.
Anyone who needs full power and control at low speeds—toolmakers, woodworkers, and carvers—will need larger, higher-output motors.

For a jewelry workshop, woodworking workshop or product designer, you need good quality, general purpose machines that work well across the entire speed range. In the recent past there were many manufacturers of flexible shafts, but today their number has narrowed significantly. Here are the leading manufacturers:

A brand that has become synonymous with the tool itself, Foredom is by far the most commonly found in workshops and shops; it's a template, a pattern, if you will, on which other brands are based. Most specialized handpieces and control pedals designed for operation are built around this basic concept.

For many years, the workhorse was the Foredom with an “S” motor that ran at 1/8 hp. Since then the drill has been upgraded to “SR” with a more powerful 1/6 HP. With. motor and a maximum speed of 18000 rpm, which can operate in forward or reverse direction with a switch. This feature is much more convenient than it might seem at first glance.

When the drill gets stuck, gets stuck in the metal, switching the motor back on shows the difference between the normal and reverse motors; in the first case, a broken bur or drill will get stuck so that you have to drill out, and when there is a reverse function, you simply switch and slowly pull out the bur, drill. Reversing can also help avoid the dreaded unnecessary directional dullness on steel and brass wire brushes that results from rotating in one direction.
A right-handed master can direct debris away from the face by installing a reverse switch, and also reduce the “jumping” of the working tip and nozzle from the edge of the product by turning on the reverse motion of the motor.

Any tool that has an indirect action—a tool that cuts, grinds, or polishes by rotating clockwise or counterclockwise (such as abrasive wheels)—can add an advantage to the craftsman's work.

But there are some peculiarities: standard drill bits, burs and cutters are designed only for cutting in a straight direction. They're useless cutting tools in the opposite direction. As much as we'd like to, a tool with a reverse rotation feature won't push metal back into the hole once you've drilled too deep.

And any attachment mounted on a tip near a screw-type shaft can have a common problem where the right-hand thread of the screw begins to loosen in the opposite direction. Foredom makes a range of screws, with different threads, which are available on their website. However, the reverse function is a good feature and it offers the chance that there may be a new industry standard for drills.

Foredom SR comes with a standard 39-inch approximately 1m rubber outer shell and inner cable. Specialty 45" - 1.1m and 66" - 1.7m shells, as well as softer, more pliable neoprene shells available.
The basic Foredom SR drill comes with an electronic foot pedal and an adjustable handpiece.

OttoFlex

This machine was made in Buffalo by a dental manufacturing company and sold to the Otto Frey Company. Other supplier companies once sold this machine under their own names, and you can find machines with the Buffalo Dental label from dental industry suppliers, but Otto Frey remains the best option acquisitions.

This drill has a 5 HP motor. With. with a maximum speed of 20,000 rpm. The OttoFlex engine body is covered in shiny chrome - it makes absolutely no difference, but wait a minute - chrome! This drill is a reliable comrade and works with most conventional foot pedals and handpieces.

The big difference between this and other brands is the neoprene shell, which is softer and more flexible. The advantages of flexibility are obvious, the only drawback of the neoprene shell is that if it gets a little loose or weakened, the more flexible shell can bring a surprise - the motor will rotate, but the tip will not. No real danger, of course, but be prepared for surprises!

Soft, aftermarket neoprene sheaths are available for other brands, but sheaths and drills are not necessarily or always interchangeable. If you need replacement parts, make sure on shore that they match the specific model and manufacturer of your drill.

Grobet and Prodigy

Drills from Grobet and Prodigy are manufactured in China. An economy class drill from Grobet (USA) usually costs less than $100. The basic kit is equipped with a 10 hp engine. sec., maximum 18,000 rpm, standard electronic foot pedal housed in a plastic housing, and a #30 stylish tip.

The relatively inexpensive Prodigy has a slightly more powerful 1⁄8-horsepower motor and the same pedal and tip style. Few people sell the Prodigy model, except Rio Grande sells the Prodigy and one or two online stores do, while Grobet drills are more widely available.

Chinese products may sometimes have a less savory reputation, but things are changing and Chinese goods are improving. Grobet and Prodigy offer an economical alternative for those who are just getting into the creative field, need a backup unit, or will use the instrument relatively infrequently.

Other Brands

Dumore, Pfingst, Pro-Craft, and Vigor, along with the discontinued Foredom model, once represented wide range and flooded the market. Why am I talking about machines that are no longer made or are not widely available? Because they can still be found on the secondary market. Avito, eBay, yard sales, and even newspaper advertisements sometimes list these cars for sale. And while Foredom doesn't stock the CC and S models, you can still find them new, in packaging from small suppliers, if you dig deeper online.

Summary of the first part:

Discouraged? I'll simplify everything. If you plan to work long hours and often at a bench, or you plan to work in metalworking or related fields, buy the Foredom SR or OttoFlex (BuffaloDental). Choice of 1⁄6-1⁄5 l. s., which these machines produce a lot, but at least 1⁄8 liters. With. If cutting operations will be performed. They cost just under $200.
If your budget is limited, buy only the machine (motor, shaft, tip and pedal). If you can find it for $20 more, then get the basic advanced kit, which includes good choice hogs, bits and accessories; they provide broad access to job opportunities. But at the same time, avoid more massive kits - they simply have too many different shortcomings, shortcomings and unnecessary functions. If you are a hobbyist or beginner, then a Grobet or Prodigy, shaft, tip and pedal is the way to go.

When you compare prices, make sure you are looking for comparable kits or systems. The Foredom SR drill may seem inexpensive until you realize that the price only includes the motor and shaft!

In conclusion

Like any tool, a drill is the perfect complement to your capabilities. It is important to remember that the operator of any tool is the key in this system. Maximizing the capabilities offered by this amazing tool is a function of control and control that you will only gain by mastering the tool through practice. It takes time, but it's the same good way spend time and acquire a skill.

How does a drill work?

1. Motor, depending on the model, rotates at a maximum speed of 14,000-20,000 rpm. Some specialized drills only reach 5000 rpm. Motor power ranges from 1/10 to 1/4 horsepower, which is typically found in drills designed for woodworkers or manufacturers that need more torque to cut or move material. Most models have built-in hangers (hooks are not provided); some models will be obsessed with the workbench.

2. Rubber or neoprene outer shell and a steel or brass inner cable assembly transfers the rotational force of the motor to the handpiece. It's the "flex shaft" that gives the machine its name, and it's usually about 3 feet (91.4 cm) long. The internal cable is the part that breaks most often, but it's easy to replace.

3. Tip- which large selection on the market and accessories for them. There are tips various styles and configurations. Many, if not most, are interchangeable. The #30 tip is the most popular and is the default for most flex shaft models. These tips have an adjustable chuck that is loosened and tightened using a chuck wrench.

4. Pedal- the mechanic uses a speed control - most often a pedal - to change the speed of the machine to suit his task. There are several options available, as well as a speed control device on the drill unit itself installed on the workbench.

A wood carving drill, equipped with various working attachments, is equipment with which wooden surface You can apply not only various inscriptions and patterns, but also relief images. To perform wood carving, you can use not only special engravers designed for working on this material, but also drills that are equipped in dental offices.

Beginning craftsmen who find a wood engraver to be a complex piece of equipment should obtain the appropriate knowledge and master certain skills before starting work. On modern market There are many models of such devices, which can cause certain difficulties when choosing, especially for those who are just planning to get into this exciting thing like wood carving.

How to choose equipment for woodworking

Knowing the basic criteria that should be followed when choosing a wood engraver, purchasing the right model is not so difficult. Such criteria, in particular, are the power of the drive motor and the number of revolutions it can produce, as well as the torque it develops.

None of them modern models The drill, unfortunately, does not combine two important characteristics: the ability to operate for a long time at high speeds and resistance to increased loads arising during the treatment process. In this regard, craftsmen who are going to purchase wood drills have to make a choice between powerful, load-resistant and high-speed devices. The best option in such cases, it is necessary to purchase two models of engravers at once, with different technical capabilities.

If you are going to devote yourself to wood carving and immediately purchase technical equipment for these purposes, it is better to opt for such equipment as:

• a powerful drill, the working tip of which has a reinforced design;
• micromotor of compact size, capable of operating at high speeds.

You can save on purchasing an engraver for wood carving by making such a device yourself. To make your engraver, you must prepare:

• electric motor from old washing machine or other household appliances(its power must be sufficient for the device being manufactured);
• elements of a belt drive, with the help of which rotation from the electric motor shaft will be transmitted to the arm of the drill;
• the sleeve itself (flexible shaft) of the device;
• a nozzle in which the working tool used will be fixed.

If the electric motor and belt drive mechanism can be selected from old household appliances, then the flexible shaft and nozzle will have to be purchased additionally. Naturally, to make a drill with your own hands, you will need at least minimal technical knowledge and skills, as well as a set of plumbing tools.

You can make an engraver for wood carving yourself even more in a simple way. To do this, you need to purchase a flexible shaft that can be installed on a regular electric drill or a screwdriver. Using such a shaft with an attachment eliminates the need to think about how to connect the drive motor to the drill arm.

Types and manufacturers of drills

The domestic market offers a wide variety of drills and engravers that can be successfully used for wood carving. When choosing such equipment, you need to know for what tasks it will be used and in conjunction with which tool.

Drills for technical purposes

Drills in this category are distinguished by sufficiently high power, which makes it possible to effectively use such equipment to solve various technical problems. It is also represented by Russian products trademark“Profile”, under which sleeveless drills are produced, equipped with a pedal, which makes working with them more convenient and comfortable. Using technical drills produced under this brand, you can perform various technological operations - drilling, boring, grinding, etc. Meanwhile, when choosing such equipment, you should keep in mind that it operates at low speeds.

The Profile-B-04 drill chuck is designed for attachments with a shank diameter of up to 6.5 mm

Powerful, reliable and functional drills for technical purposes are produced by American company Foredom SR. They can be equipped with power collet and quick-release attachments, which allows you to successfully use various types of working tools. It is also important that purchasing spare parts and components for drills from this manufacturer on the domestic market does not present any particular problems.

Micromotors

Micromotors are compact drills or engravers that can be used for wood carving. Their design features consist in the absence of a flexible shaft and the location of the drive motor at the rear of the working nozzle itself. It is very convenient to use such engravers for making fine wood carvings.

Among similar products produced by domestic manufacturers, we should highlight the micromotor model DPM 25-2, which is equipped with a specialized medical tip. Despite its relatively low cost, this micromotor has decent technical characteristics, it is easy to use and can be used in conjunction with various types of working tools. However, it should be borne in mind that the medical handpiece with which such a micromotor is equipped is not intended for intense loads, therefore it is advisable to use such equipment only for performing simple work and fine wood carvings. If the operating conditions are not observed, the micromotor of this model may have a motor failure that cannot be repaired, but can only be replaced with a new one. However, all the above-described disadvantages of the DPM 25-2 micromotor are compensated by its low price.

Micromotors produced under the Marathon and Strong brands are much more reliable and functional, but also more expensive. Along with high power (65 W), such micromotors are capable of providing high rotation speed of the tool used for carving (up to 30,000 rpm). Many experienced woodcarvers, already well versed in the equipment available on the domestic market, choose micromotors from these brands to equip their workshops.

Micromotors, regardless of their modification, are not intended for use in conjunction with large tools, which can quickly render them unusable.

Mini drills or compact drills with flexible drive

Mini-drills or engravers for woodworking, equipped with a compact drive, a sleeve and a convenient working attachment, are presented on the domestic market with products from different manufacturers. You can consider the capabilities of such equipment using the Hammer MD 135A drill model as an example. made in China, which is popular among those involved in wood carving. At a low cost, the mini-drill of this model has decent characteristics and comes in a good package, which includes:

• compact drive unit;
• flexible shaft;
• telescopic rod, intended for fastening the device;
• a set of 40 working tools.

If we talk about the main technical characteristics of the drill of this model, they are impressive: the rotation speed of the tool is 10,000–32,000 rpm, the power of the device is 135 W. It should also be noted high quality the assembly of this drill, as well as the ergonomic shape of its body and flexible shaft attachment, which are convenient to hold in your hands during processing. When turned on, the Hammer MD 135A wood carving engraver does not make much noise or vibrate.

To expand the functionality of the Hammer MD 135A drill, it is enough to purchase additional set working tools of various types. During the process of running in a drill of this model, performed at idle speed, you can notice that the speed of the device “floats”. When the Hammer MD 135A mini drill is running under load, no such problems are detected.

The working tools included in the standard set of a drill of this brand can be divided into several categories:

1. cylindrical tools with abrasive work surface which are used to perform grinding work;
2. milling cutters, which are used to select and grind the surface being processed;
3. rollers with an abrasive coating applied to the head.

If we analyze the reviews of those who have worked with the Hammer MD 135A drill for some time, we can draw the following conclusions about its most significant advantages and disadvantages.

1. The reliability and functionality of the mini-drill are at a fairly high level.
2. The Hammer MD 135A drill can be successfully used both for making shallow grooves and for grinding surfaces with complex configurations.
3. The price of this mini-drill is low for equipment of this level.
4. The collet clamp of the drill, although highly reliable, is not very convenient to use.
5. There are not many attachments that come standard with the equipment, and their quality and durability leave much to be desired.

To perform complex and voluminous work on wood and processing hardwood, you should choose more powerful drills equipped with cam rather than collet clamping mechanisms, and also use a quality tool.

We offer you to consider several popular models of drills intended for hobbies and light repair work. In the article we will compare operational and technical specifications network and battery devices. They are produced by well-known companies, but belong to different price categories.

Most hand-made projects cannot be imagined without the use of electrical assistants. For a number of reasons, construction units are not always suitable for handicrafts, so some companies produce special products - “universal microtools”.

These small hand-held devices called differently: engraver, drill, mini-drill, straight grinder, dremel. This is because such a tool is multifunctional; it embodies the features of several devices. In essence, this is a universal drive that can be equipped with a large number of working attachments and perform a lot of machining operations, such as:

• cutting;
• drilling;
• milling;
• grinding;
• stripping;
• polishing;
• sharpening

It’s not for nothing that, for example, the Bosch product is defined by its developers as multifunctional “ rotary tool" For home handyman The ability to work with one hand and process ultra-precisely, including miniature parts and workpieces, is valuable. Very useful qualities household engravers are considered: high speed of movement of the equipment, absence of vibration, low level noise.

Similar tools are also used in many areas professional activity(dental services, jewelry, car service, various types of finishing...). But they can be specifically designed and highly specialized, including large mass and dimensions, or, for example, powered by compressed air. We are interested in lightweight (up to a kilogram) compact engravers, which are powered by an available living conditions electrical energy, and which allow you to install many different attachments - disc holders, brushes, felt and cylinder holders, burs, drills, cutters... The selling idea of ​​this multitool is simple - by purchasing just one device, the master completely covers all questions regarding the tool.

Networked drills

Dremel is considered a leader in its field of activity. Hobby drills are the company’s calling card; it is not surprising that this is what people often call all rotary multi-tools (“dremel”). The 4000th model is the flagship of the networked line of drills from this manufacturer and has many traditional and advanced characteristics.

The layout is no different - an elongated straight body-handle, which contains a motor, a spindle with a clamp at the end, and controls. The casing is made of plastic with many pronounced rubberized linings.

At the front of the tool, near the clamp, there is a replaceable rubber casing for finger grip; the user, depending on the type of work, can choose either a cylindrical shape or with three edges. The start and shaft lock switch are located in different buttons, located at hand, but they are difficult to touch accidentally. The speed control wheel is hidden in the rear, where there is also a recessed steel loop for hanging the tool.

The main features of the Dremel 4000 drill lie in its technical solutions. First of all, let's pay attention to the performance of the motor. 175 watts allow you to get quite a decent torque and successfully process hard and viscous materials. Note that this power has almost no effect on the weight of the car, which is only 660 grams, while the weight of less famous competitors of similar power exceeds a kilogram.

This drill is high-speed, it accelerates to 35 thousand rpm, but if this is necessary for a specific operation, the speed can be limited to 5000 rpm. At the same time given parameters will be supported automatically, regardless of the load level. This is called "constant electronics" and is often used in construction tools.

The attachments are fastened using a collet clamp with a maximum working diameter of 3.2 millimeters. The most inexpensive set includes 45 attachments, a flexible shaft for precise work in hard to reach places, an additional handle, all this fits into a soft bag.

There are several wider sets, the most advanced is the Dremel 4000 Platinum Edition with 128 attachments and 6 additional elements(angle attachment, compass, vertical stand holder...), the set is offered in a monumental aluminum box. The retail price of Dremel 4000-1/45 is about 5.5-6 thousand rubles, the “platinum” set costs about one and a half times more.

This drill is manufactured by a well-known German company, which presents many different models on the market, including those for industrial use. FBS 12/E, like other company products, is made of very durable fiberglass reinforced polyamide. The device turned out to be light and compact, its weight is about 450 grams, and the case diameter is about 35 mm. It looks like nothing new, there is a shaft lock, a speed regulator, and a start switch.

At the same time, the network Proxxon FBS 12/E is an unusual device. The main feature of this drill is its low-voltage power supply. It operates on 12 volt DC. As you understand, there are no batteries here, and the current is converted through a step-down transformer. The manufacturer recommends using branded adapters designed to operate with a current of 1 ampere or more. By the way, the transformer is not included in the kit; you will have to purchase it additionally.

What does the 12-volt solution provide? The machine is safe when stored high performance. Such a tool can be used where the workpiece needs to be cooled with liquid, for example, in the production of jewelry - for processing precious stones.

It should be noted that the technical characteristics of Proxxon FBS 12/E are not entirely traditional. First of all, the low maximum speed of 15,000 rpm is striking, which is more than 2 times lower than most 220 V models. But this means that there are no problems with a drop in torque levels. Even this speed can be reduced - as much as 3000 rpm, this is done smoothly, using thyristor control electronics “with feedback”. Another plus: FBS 12/E consumes a very small amount of energy, about 100 W per hour.

To change attachments, a three-jaw keyless chuck is installed on the drill. But it is possible to replace it with collet clamp to the required diameter of the tool shanks. There are few attachments in the set (they, together with the device, are placed in a plastic case), but for additional equipment you can choose from hundreds of items that are in the price lists of this brand. Proxxon FBS 12/E costs about 2200-2400 thousand rubles.

Cordless drills

Dremel 7700-15 Hobby

The mobile autonomous drill is intended exclusively for creativity, this is clear even from the name. The battery used is simple, made using NiCd technology. Its capacity is 0.7 Ah, and the voltage is 7.2 volts - this is enough for short-term work with most materials, but does not allow the machine to be used as a professional one.

The speed range of the 7700 model is quite limited. You can select only two modes - 10,000 rpm and 20,000 rpm. Although the two-speed version is already outdated, drills are still produced without a speed controller at all.

This model can impress. Its ergonomics. Weight less than 300 grams, length 175 mm - very good indicators.

The tool is intended for those who often work outdoors, do light work and do not need an expensive, powerful device with a large number of attachments and accessories. A Dremel 7700-15 Hobby drill with 15 attachments, a battery and a charger costs about 3,000 rubles.

The Germans delayed the release of a cordless drill for a long time, but they immediately produced a reliable, productive model capable of solving serious professional problems. The GRO 10.8 V-LI is a “multifunctional rotary tool” that comes in a blue casing. Compact (250 x 53 mm) and ergonomic, it weighs only 600 grams including battery.

What is the “professional bias” of the unit? The developers powered the machine from a compact 2 Ah system battery with a voltage of 10.8 volts, which powers the entire line construction tools(more than 20 devices). That is, we can use a unified battery from another product that is in stock at any time. By the way, to make the product more profitable, the Bosch drill is sold both fully equipped and without a battery or charger.

Despite the battery power, the Bosch GRO 10.8 V-LI Professional at idle speed develops a high shaft rotation speed of up to 35,000 rpm, which can be reduced by the wheel to 5 thousand.

As usual, German designers make full use of battery technology and installed it on the machine LED backlight working area. The remaining battery charge level can be monitored using 3 indicator LEDs.

The cost of the Bosch GRO 10.8 V-LI, released in 2014, is still relatively high, about 4,000 rubles, but this instrument already has fans. Direct competitors of the GRO 10.8 V-LI are the Dremel 8200 and 8100, which have similar characteristics and a battery with the same power ratings. The price of the 8100th model is about 4,500 rubles, Dremel 8200 (35 attachments) with battery (Lithium-Ion/ECP) and “fast” charger costs approximately 5200 rubles.

Video on the topic

Anyone who has been in a dentist's chair at least once in their life is familiar with such a technical device as a drill. Meanwhile, a dental office is not the only place, where a pneumatic or electric drill is actively used as the main working equipment. Using such devices equipped with attachments various types, professional specialists and home craftsmen perform the finest processing of parts from different materials, produce decorative products, and also successfully solve a whole list of other problems.

Areas of use

The drill, the main working part of which is a shaft rotating at high frequency with the function of a spindle that transmits rotation to the tool, is today actively used by both professionals and home craftsmen, who also appreciate the versatility and efficiency of such a device. In addition to the already mentioned dentistry, where pneumatic drills are mainly used, such devices are necessary for:

• instrument making, where drills are used as mini-drills and compact polishing devices;
• manufacturing products for decorative and applied purposes (carving wood, stone and bone, applying inscriptions and patterns to the surface of products made from various materials (engraving));
• jewelry making, where using similar equipment they create beautiful jewelry from various materials.

In order to turn a drill, which is essentially a driving device, into a multifunctional equipment, it is equipped with special working attachments. Each of them is designed to solve specific technological problems. Thus, the most popular types of working attachments used in conjunction with drills are:

• drills that turn the drill into a mini drill;
• cutters, with the help of which a drill performs processing of both flat and shaped surfaces, as well as holes of various configurations;
• mini-disk tool designed for cutting the material being processed;
• an engraving tool used to apply inscriptions and patterns to the surface of the workpiece;
• tools that are used to clean the surface being treated from traces of corrosion and various contaminants, as well as grind and polish it.

Modern models of drills differ from conventional dental devices not only in that they are electric rather than pneumatic, but also in the presence additional options(in particular, the ability to adjust the spindle speed). The most reputable manufacturers of such devices are Dremel, Omax, Proxxon and PowerMax.

If we talk about the degree of autonomy of electric drills (engravers), then depending on this parameter, such devices are divided into the following types:

• stationary equipment;
• manual engraving devices;
• compact cordless drills;
• models operating from a central power supply network.

Design Features

When deciding how to choose a drill or how to make it yourself (which is quite possible), you should understand the design and operating principles of this equipment. The main elements of any drill are:

• a tip on which working attachments are installed;
• electric motor, which can be brushed or brushless;
• a device that provides power to the drill motor.

It is clear that a pneumatic drill, powered by compressed air energy, does not have an electric motor in its design. If a brushless type electric motor is installed on the drill, it additionally contains a special control unit that ensures the creation of variable magnetic field between the stator and rotor of the drive motor. A commutator drill, unlike a brushless one, can be connected directly to a DC source.

When comparing commutator and brushless type drills, you need to pay attention to the following points:

1. Collector drills are easier to manufacture and, accordingly, cheaper. No expensive control unit is required to ensure their operation.
2. Brushless drills are more powerful and are capable of providing a rotation speed of the tool used in the range of 50–60 thousand rpm, while collector ones develop a speed not exceeding 45 thousand rpm.
3. The presence in the design of commutator devices of an intensively rubbing unit (brushes and commutator surface) leads to their significant heating during operation, which requires ensuring effective ventilation of the electric motor of the drill.
4. The presence of a rubbing unit in the design is also the cause of a significant loss of power in collector-type drills. Because of this, the efficiency of collector devices is only 60–70%, while for brushless devices this parameter is at the level of 90%.
5. To increase the power and torque generated by brushed electric motors, it is necessary to increase the size of the device.
6. The brush-commutator assembly itself is the reason for the large size of commutator devices when compared with brushless ones.
7. Collector drills are also characterized by more high level noise during operation.
8. The service life of commutator drills is slightly shorter than that of brushless ones.

In general, to summarize all of the above, we can say that in terms of the ratio of the most significant parameters, collector drills are the most preferable option in most cases, which is confirmed by the high popularity of the devices. of this type. Brushless drills are more expensive and difficult to operate and maintain when you often have to process very hard materials.

How to choose the right drill

Regardless of what you are purchasing the device for - for minor works in the home workshop or for professional use, – it is very important to choose this mini-equipment correctly. Parameters of such a device that you should pay attention to special attention, are:

• rotation speed that the drill spindle is capable of developing;
• device power;
• force, or torque created by the drill.

A set with two drills: a full-fledged mains one for basic work and a miniature low-voltage one for “small things”

Many of those who purchase a drill to perform simple work in the home workshop opt for high-speed models, which is not entirely correct. For most of such work (and for solving most professional problems associated with drills), models capable of spindle rotation speeds of up to 35–40 thousand rpm are quite suitable. In particular, the tool used to process ceramics must rotate at this speed, and for work on more soft wood More modest parameters are sufficient. It should also be borne in mind that a drill capable of operating at very high speeds is much more expensive than its slower-speed counterparts. Therefore, you need to think carefully about whether you will need options on an expensive device that you will use very rarely or not at all.

A more important practically important characteristic of any drill is the torque that such a device is capable of developing.

There is a direct relationship between torque and power of the drill, so special attention should be paid to this parameter. Compact drills, which are often called micromotors, have the lowest power of the models on the market today. Such mini-devices, the working attachment of which is combined in one housing with a drive electric motor, cope quite well with the finishing of products made of various materials. Working attachments for this equipment (both straight and angular) are small-diameter drills, mini-mills, grinding and polishing heads. It should be borne in mind that micromotors, like pneumatic engraving tools, are not intended for use in conjunction with massive working attachments and for performing rough work.

Technical drills have higher torque and, accordingly, power. Such devices, the straight or angular working attachment of which is driven by flexible shaft, are equipped with a powerful electric motor that can successfully cope even with fairly high loads. The working attachments themselves, which are equipped with such drills, also have a reinforced design, which allows them to be used in conjunction with large and heavy tools and with their help to perform rough processing of products made from various materials.

Technical drills, which have high power and operate mainly at medium speeds, are not very suitable for performing delicate work. This is also explained as follows. The working attachment (straight or angular) installed on such equipment is driven by a flexible shaft, which puts a lot of stress on the hand, and this can cause defects when performing delicate work.

We are often asked: what bone carving drills do we use and which one is better to buy, What should you pay attention to? Therefore we decided to write brief overview, it is based solely on our personal experience accumulated over many years of work. It should be noted right away that there is no universal drill for carving. The wide selection of different models of drills on the market often confuses beginners. Each drill has its own characteristics and is intended for specific purposes.

Which drill should you choose?

Choose a drill suitable for carving bone or wood, among the many offerings on the market, is actually not that difficult. Drills vary in engine power, speed (rpm) and torque.

Very often, when choosing, they pay attention to the number of revolutions, but in practice the number is 30,000 rpm. is superfluous and is used in carvings extremely rarely. For example, to work with a large cutter, 10,000 rpm is quite enough, but to work with small burs, sometimes more than 20,000 rpm is required. Unfortunately, there is no single drill that can simultaneously withstand the high loads of a large cutter and can operate at high speeds for a long time. Therefore, the most important and only the right choice will purchase at least two drills with different characteristics.

The optimal solution for carving wood or bone would be to purchase the following drills:

1. Powerful drill with reinforced tip.
2. Compact micromotor capable of operating at high speeds.

Technical drills

For the initial stage, you need a powerful technical drill capable of clamping a cutter with a shank with a diameter of 6 mm. Those who like to save money and tinker can avoid some costs by doing this, for this you can take, for example, a motor from a washing machine or another powerful engine and use a belt drive to connect it to the sleeve from the drill, in this case you will still have to do a fair amount of magic, but the sleeve and tip itself still have to buy it. This is one of the cheapest options; at first we used it. Of the minuses, it can be noted that sleeves adapted for belt drive are now quite difficult to find and they are quite unreliable, because They were originally intended for dental purposes and now such samples are no longer used.

There are quite powerful sleeveless drills "Profile" with a pedal, created by Russian engineers, very reliable, practically “indestructible”, allowing you to perform wide range technical operations such as drilling, grinding and much more, this drill has a three-jaw chuck, which is very convenient for these purposes. However, having tested it, it should be noted that it has low speeds, with a fairly high torque, and for threading, a three-jaw chuck is less suitable than a strong collet clamp.

Another example of domestic production, but with a sleeve, also a fairly powerful drill, but low-speed.

We have been using a drill for many years Foredom SR series, produced in the USA, it can be noted that it is reliable in operation and fails extremely rarely under high loads. All spare parts can always be easily purchased in stores that sell tools for jewelers, such as Sapphire or Ruta in Moscow. There is also a large selection of tips, from power collet tips to convenient quick-release ones.

This drill has an optimal power of 125 W. It’s quite enough for rough cutting of a mammoth ivory workpiece and the speed is quite decent 18,000 rpm. However, for elaboration small parts it is not entirely convenient even when using special tips, of which there are quite a few offered; the range for this drill is quite large, however, this is only our subjective opinion. First of all, the presence of a flexible shaft. At long work it puts extra stress on the hand, and at 18,000 rpm. It starts to work very noisily, which creates a lot of strain on the ears and reduces comfort at work. There is also a Chinese analogue, which costs much less, about 5,000 rubles, but is assembled quite decently, the drill was tested by us and our colleagues, and had no particular complaints. It is less powerful, but as it turned out, this power is quite enough for normal operation. This drill is marked SS. It should be noted that the original and Chinese drills have some differences, for example, the handpiece from one will not fit the other drill.

Micromotors

Micromotors or mini drills are more compact and do not have a flexible shaft, unlike powerful drills. Their motor is mounted directly behind the tip. They happen the same way Russian made and foreign. These drills are designed for more fine workmanship with a blank, they are more convenient.

There is a drill made in Russia DPM 25-2 with medical tip. It fits very comfortably in the hand, you can quickly change burs and is affordable. However, the medical tip cannot withstand heavy loads and with constant use can quickly fail. And also, the micromotor itself cannot be repaired, since the carbon brushes wear out over time, and it is not yet possible to replace them. Having exhausted its resource, you will have to change the engine itself or the entire drill. Otherwise, it’s not a bad, budget and convenient option.

There is also a Korean version, this drill is very attractive for its functionality and reliability, but on the Russian market the drill Marathon or Strong It's not cheap, about $200 or more. It is high-speed up to 30,000 rpm. and a power of 65 W, which is very high for a micromotor; we work with these drills.

Do not forget to use a hood and safety glasses when working with a drill, especially when rough processing a workpiece made of bone or wood. You can use a regular vacuum cleaner as a hood; there is also a synchronizer for a vacuum cleaner from the company Proxxon, which will turn the vacuum cleaner on and off simultaneously with the drill, which is very convenient.

So, our review has come to an end; we examined and compared only those drills and micromotors that we use or have previously used ourselves. We hope we were able to answer most current issues problems that worry most beginning carvers when choosing a tool. If you still have questions, ask your questions in the comments, we will try to help you decide on the choice of a drill suitable for your needs. Tell us what carving tool you use, share your experience?