Classification and features of the choice of bits for a screwdriver

For repair work, assembly or dismantling of the retaining elements, power tools are used to facilitate the process of fastening and removing the retainers. Screwdrivers and drills can fail due to an incorrectly selected nozzle, therefore, for confident and high-quality multidimensional work, craftsmen use bits. Let's take a closer look at the modern types of bits, what they are, and how to use them.

A bit is a rod that is attached to the chuck of a power tool, and the selected drill is already inserted into it. The working surface of the nozzle is a hexagon. Each bit corresponds to the type of fastener.

Tool accessories consist of:

• drill;
• magnetic / regular bit and holder (extension cord).

Bits for a screwdriver must be selected for the size of the fastener head and the characteristics of the nozzle itself. Taking into account all these criteria, the sets are made up of common in practice nozzles from 2 to 9 mm.

Each nozzle is distinguished by the geometric shape of the working surface. On these grounds, the following categories are distinguished.

• Standard. They are heads for bolts, straight handpieces, cross-shaped and hexagonal for screws, star-shaped.
• Special. Equipped with various springs with a limit stop, used for fixing drywall sheets. They have a triangular shape.
• Combined. These are reversible attachments.

Extension cords are available in two varieties:

• a spring - a nozzle inserted into a bit, as a rule, lends itself to rigid fixation;
• magnet - fixes the tip with a magnetic field.

These bits are present in all bit sets, as they are used in almost any job. Bits for a straight slot appeared first, today such nozzles are used in working with screws and screws, the head of which has a straight section.

Equipment for a flat slot is marked S (slot), after which there is a number indicating the slot width, the size range is from 3 to 9 mm. All nibs have a standard thickness of 0.5-1.6 mm and are not labeled. The tail indicates the material from which the nozzle was made. All elements have increased erosion protection and hardness.

Titanium slotted bits are incredibly durable. Gold plating is swept away with the letters TIN, indicating that the tip is made of titanium nitride. The width of such tips is larger than the standard one - up to 6.5 mm, and the thickness is slightly less - up to 1.2 mm.

Slotted nozzles are often reversible, in combination with a cruciform tip. This is due to the versatility and frequent demand for the product. The thickness of a flat bit is usually not indicated, since it has an internationally accepted standard from 0.5 to 1.6 mm.

Some rigs are available in an extended version. Due to the length, the possibility of tight contact between the screw and the nozzle is achieved, which improves the quality and accuracy of work.

Many firms produce bits with their own markings, but in a standard form. Philips puts the letters PH on the crossheads and produces them in 4 sizes: PH0, PH1, PH2 and PH3.The diameter depends on the size of the screw head. The most commonly used PH2 is used in home work. PH3 is used by craftsmen in car repairs, furniture assembly. The length of the bits ranges from 25 to 150 mm. Flexible extensions are designed for fastening work in hard-to-reach places.

Pozidrive cruciform bits are double-shaped. Such a nozzle ensures reliable operation with torsional moments; strong adhesion occurs even when the screw head is turned at a small angle in relation to it. The size range of bits is marked with the letters PZ and numbers from 0 to 4. The PZ0 tooling is designed for small screws and screws with a diameter of 1.5 to 2.5 mm. The largest head PZ4 is used to fix the anchor bolts.

Hex head fastening material is secured with hexagonal bits. Such screws are used when assembling heavy furniture, repairing large-sized equipment. A special feature of hex fasteners is the slight deformation of the bolt head. This should be taken into account when twisting the clips.

Bits are divided into sizes from 6 to 13 mm. The most common bit in everyday life is 8 mm. It is convenient for them to tighten screws and carry out roofing work. Some bits are specially magnetized with metal hardware. Because of this, magnetic bits are one and a half times more expensive than conventional bits, but at the same time they greatly facilitate and speed up the work with fasteners.

Such a tip resembles a six-rayed star in shape. These bits are used in the repair of cars and foreign household appliances.

The tips are available in sizes from T8 to T40, indicated in millimeters. Sizes below the T8 value are produced by manufacturers for highly specialized screwdrivers used in microelectronic technology. Star-shaped nozzles also have a second marking - TX. The number in the marking indicates the distance between the rays of the star.

The six-beam insert creates a secure grip on the bit to the bolt without excessive force. This shape minimizes the risk of screwdriver slipping and bit wear.

Torx hole campaign bits come in two flavors: hollow and solid. This point should be considered when buying.

Triangular tips are marked with the letters TW (Tri wing) and size range from 0 to 5. The head of such a tool looks like a trihedral with rays. Models are used with Phillips screws. This type of screws is usually used in foreign household appliances to protect against unauthorized opening of the equipment. To fix the drywall, nozzles with a limiter have been created, which does not allow the screw to be tightened deeper than the stop.

Square bits are of a highly specialized nature. Designated with the letter R, the slot consists of four faces and is available in four sizes. Square bits are used in the assembly of large furniture.

Fork bits are flat-slotted with a central slot. They are designated by the letters GR and come in four sizes. Type - standard, extended, length up to 100 mm. The four- and three-bladed bits are labeled TW. These are professional attachments used in the aerospace and aviation industries.

Non-standard types are included in conventional bit sets, but are not used in home repairs, so it is advisable to give preference to sets containing standard and Phillips nozzles for a nut, screw, screw and other fasteners.

Angle and long screwdriver nozzles are designed for work with fasteners in hard-to-reach places. They are flexible and solid, allow you to screw in and out the screws. Made of durable materials, non-magnetic.

Impact or torsion nozzles are designed to relieve the effect of the torque that occurs when the screw is screwed into the soft layers of the working surface. These attachments are used only with an impact screwdriver and do not require an increased load on the device. Bit markings are color-coded.

Particular attention should be paid to the material from which the bit is made, its coating. Most of the work is done by the surface of the nozzle, and low-quality materials will lead to rapid tool wear.

Quality bits are available in various alloys:

• molybdenum with vanadium;
• molybdenum with chromium;
• will win;
• vanadium with chromium;
• high speed steel.

The latter material is cheaper and subject to rapid wear and tear, so it is not considered when comparing performance.

The soldering of the bit is made of spraying:

• nickel;
• titanium;
• tungsten carbide;
• diamond.

The outer coating is always applied, it provides protection against corrosion, increases wear resistance and improves the strength of the material from which the element is made. Titanium soldering appears in golden hues.

There is no universal answer to the question of which bits are better, but preference should still be given to proven brands. Cheap products not only will not allow you to perform the task in a high-quality way, but also damage the tool.

Manufacturers and characteristics of the kits:

• Bosch 2607017164 - quality material, durability;
• KRAFTOOL 26154-H42 - adequate price in relation to product quality;
• HITACHI 754000 - multifunctional set of 100 pieces;

• Metabo 626704000 - the best tooling quality;
• Milwaukee Shockwave - High Reliability
• Makita B-36170 - running bits with manual screwdriver, high quality;

• Bosch X-Pro 2607017037 - ease of use;
• Metabo 630454000 - increased safety margin of the tooling;

• Ryobi 5132002257 - large set in mini-case (40 pcs.);
• Belzer 52H TiN-2 PH-2 - medium wear of elements;
• DeWALT PH2 Extreme DT7349 - high durability.

The question of bit exploitation always remains relevant.

• German sets from the company Belzer and DeWALT represent products of above average quality. In the first minutes of operation, wear and tear of fasteners appears, small breaks of the bit, breakthroughs on low-quality elements, but after a few minutes the wear stops. These changes are happening with all the bits of different firms. German bits are the most impact-resistant.
• In large sets HITACHI 754000 bits of all sizes and types are presented, they are suitable for craftsmen of large repair and construction companies. The quality of the bits is average, but it is compensated by the number of nozzles. With a careful attitude, the service life will be unlimited.
• Kraftool company presents chrome vanadium alloy tips. The set consists of 42 items, one of which is a case. ¼ ”adapter included.

• Makita (German company) - a set of chrome vanadium steel, represented by common types of splines. The bits are designed to work with a screwdriver, but the kit also includes a manual screwdriver. In addition, there is a magnetic holder. All elements are of high quality.
• American Milwaukee Set provides craftsmen with work surface bits, each of which is designed with Shock Zone technology, which protects the bit from kinking during operation. Excellent elasticity and impact resistance of the material ensures a long service life.
• Metabo set highlighted with color coding. Each type of spline is color coded to make it easier to store and retrieve a particular bit. The set contains 9 elongated bases of 75 mm and 2 nozzles.

• Ryobi Is a Japanese company that focuses on duplicating popular bits in different lengths.The magnetic holder is made in a non-standard format, looks like a bushing on a hexagonal shank, because of this, loose magnetic fixation of the fastener and the bit is possible. In general, the set has sufficient strength and quality materials.
• Bosch has established itself as a company that produces quality products that enjoy the prestige of craftsmen. Most used bits are gold titanium coated, but tungsten-molybdenum, chrome-vanadium and chrome-molybdenum bits are more durable. Titanium is replaced with nickel, diamond, and tungsten carbide to protect against corrosion and reduce wear. The titanium coating increases the price of the product, but it will also last longer. For short-term and rare works, you can choose ordinary hardware.

• If you need to replenish the set with piece copies, you should take a look at the tools by Whirl Powermarked with green markings. They have excellent hardness and magnetism, the fasteners are held for a long time. The bit adheres tightly to the chuck, does not fall out. The standard bit WP2 in most cases is used to fix screws, but for self-tapping screws, WP1 is intended. The length of the bits is different, the size range is 25, 50 and 150 mm. The tips have notches that are responsible for the wear resistance of the material. Bits of this brand have proven themselves in the market, they are used by construction firms and private craftsmen.

If you buy a piece by piece, it is important to select models with:

• the presence of a protective coating;
• high impact resistance.

When purchasing a set, you should pay attention to slightly different parameters.

• The material from which the bits are made. The better it is, the fewer problems will occur in the work.
• The way the item is processed. There are two types of processing. Milling is the least durable option due to the removal of the surface layer of the material. Forging is a homogeneous structure. Heat treatment of the bits allows them to be used in various modes with increased load.
• Profiling. Designed to facilitate handling difficult-to-release fasteners.

• Micro-roughness. Bits with rough edges, coated with titanium nitrides, are used to secure fasteners with special coatings.
• Hardness. The standard value for most attachments is around 58-60 HRC. Bits are divided into soft and hard. Hard bits are fragile, but they are more durable. They are used for low torque fasteners. Soft, on the other hand, are designed for hard mounts.
• Design. Metal tips should not be used in work where there are chips from the same material. This will make the fixing process more difficult and will lead to wear on the workpiece.

Before starting work, it is worth deciding on the screwing depth of the fasteners and adjusting it. To replace the magnetic holder, it is necessary to remove the chuck, mount, coupling, after which all the parts are inserted back into the screwdriver.

After selecting the nozzle, the configuration of the screw head, its size, types of recesses are determined, the bit is installed in the center of the open cams of the holder. Then the sleeve is turned clockwise, and the bit is fixed in the cartridge. To remove or change the nozzle, it is necessary to turn the chuck counterclockwise.

If a key chuck is used, the key is turned clockwise, inserted into its designated recess in the chuck of the power tool. At the same time, the tip of the bit enters the groove of the screw. Double-sided bits do not need to be clamped in the chuck attachment.

Further, the direction of rotation is adjusted: twist or untwist. The chuck ring is marked with markings indicating the range of values ​​required to tighten the various fasteners. Values ​​2 and 4 are suitable for drywall applications, higher values ​​are needed for hard materials. Correct adjustment will minimize the risk of damage to the splines.

The direction of rotation has a middle position, which blocks the operation of the screwdriver, it is necessary to change the bits without disconnecting the tool from the mains. The chuck in electric drills is also replaced if necessary. The sleeve itself is fastened with special screws with a left-hand thread.

The tips can be hardened using a conventional torch, but not all types lend themselves to this procedure. The method is used to increase the resistance and hardness of the material from which the element is made. The device is connected to the network or a portable power supply is used.

The battery of drills is discharged over time, it is recommended to put it on charge before work so that the speed and power of the torque do not drop. The first charge takes up to 12 hours. Braking the electric motor can damage the battery.

For information on how to choose the right screws and bits, see the next video.