How to sharpen a drill bit for wood. Circular saw (crown) for wood, concrete, metal: dimensions, sharpening. Twisted, or single-stranded

Hole or core saws represent a rather specific segment of the tool, due to technical and operational features. If classic saws work with cutting equipment that implements a straight cut, then the ring tool performs circular cutting. This, by the way, makes such models related to traditional drills. In the process of work, a hole is also formed, only of a larger diameter and with a minimum mechanical action on the structure of the material. What is more important, thanks to the design of the nozzles, the circular saw allows you to cope not only with cutting wood blanks, but also with concrete, metal and even stone.

Design features of hole saws

The ring-type saw complex is formed by two basic components. First of all, this is equipment, due to which a force is applied, causing the nozzle to rotate. The main functional element is directly cutting blade. This can be a set of different sizes, and universal canvases for a wide range of building materials, providing for the possibility of adjusting the diameter.

A mandatory component that connects the power tool and the saw blade is the holder, or shank. The saw is screwed onto the holder before the working process, and after it it is untwisted with a hex wrench. In this case, the mechanisms of fixation may differ. Hex toolholders are suitable for use in compound conventional drills, but more modern designs are integrated into the system using the SDS-plus keyless chuck. After completion of work, the hole saw must be freed from the cut off part of the material that has entered the empty niche of the crown. A special spring is designed to perform this operation. Removal of sawn products can also be done manually. This method is carried out through special slots on the sides of the saw blade.

Technical specifications

In the ring system, only one parameter remains constant and unified - this is a height equal to 40 mm. Depending on the design, it allows you to cut holes with a depth of about 32-37 mm. The main characteristic is the diameter of the crown, which is provided by the circular saw. Its dimensions are divided into two groups - less than 30 mm and more than 30 mm. In the first group minimum value will be 14-16 mm. Manufacturers usually stick to one starting value and apply it to all saws. Further, almost the entire range of digital values ​​up to 30 mm is covered.

As for the range over 30 mm, its maximum is 150 mm. At the same time, the step at the beginning of the dimensional corridor is on average 2-4 mm, and at its completion - up to 10 mm. There is also a special one produced in 168 and 210 mm formats. It is usually used in industrial applications when equipped. The diameter of the hex shank, in turn, varies from 6.4 to 15.4 mm.

Functionality

Additional functions are more related to the power tool that drives the saw blade. Depending on the workflow, cooling and dust extraction options may be required. When working with concrete and metal, loads can be excessively high, so cooling with water becomes a necessity and even a safety measure. To do this, drilling rigs are supplied with water tanks and its automatic feeding to the working head. As an alternative experienced craftsmen It is recommended to simply stop the tool at times of peak loads. Connectable dust extraction system industrial vacuum cleaner installations that include a hole saw for wood are less often supplied, although this solution is theoretically possible. The introduction of a dust collector is more justified when processing concrete and stone surfaces, the emitted particles of which not only pollute the work site, but can also be dangerous for the operator.

Wood saw 29588 from Kraftool

The German manufacturer Kraftool produces reliable and ergonomic ring-type saws. The line contains kits for different purposes, but the most popular solution is kit 29588. This is a wood typesetting hole saw, which is also used in working with plastics and drywall. According to users, the cutting part provides an almost perfect edge, which allows further use of workpieces for spot mounting work.

The set includes crowns with diameters from 60 to 74 mm, so the set will also be used in professional construction work. Although a wood hole saw as such does not require much reinforcement of the functional blade, the Kraftool developers have made a special hardening of the teeth. Moreover, their wiring is made in such a way that the sawdust in the process of cutting naturally leans back through the side slots.

Metal saw BAHCO SANDFLEX

For the processing of metal blanks, saws made of a special material are used. In particular, SANDFLEX offers 21 mm bimetal saw blades. Such equipment allows cutting non-ferrous and ferrous metals, as well as wood. Thanks to the universal holder, the nozzle can be used with hand drills and machine tools. The drilling depth in this case reaches 38 mm. Again, the drill bit was made with the expectation of independent removal of chips beyond working area. Side holes are provided for this, but depending on the model of the drill or screwdriver, it is possible to connect a separate system for removing processed products. By the way, in terms of cost, the offer from SANDFLEX is one of the most profitable in the segment - typical nozzles of common formats are available for 300-400 rubles.

Concrete saw HRS from HYCON

Equipment for working with concrete also has its own characteristics. They are clearly expressed in the design of the saw presented on the market by HYCON. This is not just a hole saw, but a hydraulic hole cutter that can also be used to cut holes in reinforced concrete, brick and stone slabs. Such high technical and operational capabilities are due to the fact that diamond spraying is used as part of the nozzles. According to its characteristics, this saw belongs to a special segment even within the industrial sector. Suffice it to say that only a specially trained team can operate the equipment. To ensure safety, the hole saw in the HRS modification is supplemented automatic shutdown. This function triggers when stuck in a solid niche, which also happens when using units of this type.

Operating rules

First of all, the user must select a suitable power base for the use of equipment. As already mentioned, it can be a drill, a puncher, and even a machine tool. Next is selected optimal mode sawing and diameter, if it is possible to adjust it. The hole making process must be carried out without excessive pressure. It is important to feel the pace of cutting set by the engine of the equipment. Otherwise, the circular saw may be deformed or even lead to malfunctions in the technical filling of the tool. After completion of the work, the processing product should be removed from the niche of the crown, after which the integrity of the saw teeth and the condition of the power apparatus should be checked.

How to sharpen a hole saw for wood?

By virtue of design features the process of sharpening such saws is quite difficult to perform at home without special equipment. With proper experience, you can use traditional way manual groove. To do this, it is necessary to securely fix the equipment and, in accordance with the requirements for the condition of the teeth, use a file or other hard abrasive to modify their geometry. If a standard set of wood crowns made of metal sheets is used, then this operation will not cause any special problems. However, bimetal and diamond drill bits for hard materials are machined only in factory lines or on specially equipped construction sites.

Conclusion

Ring type saws have many variations and designs. In choosing a fundamental criterion will be the structure and material of the fabric. In particular, the wood hole saw set is adjustable and flexible. Kits for work with metal blanks and concrete structures are more reminiscent of drill bits. The next selection step will be a specific size. It is important to bear in mind that the final diameter of the hole may be several millimeters larger than planned, therefore, in some cases, when performing spot processing, it is necessary to initially select nozzles with a smaller standard size than expected. In terms of material quality, there can also be different nuances choice, but in this part it is also worth relying on the possibility of destroying the structure of the target base. For wood and plastic, standard metal sheets will suffice, and concrete structures can only succumb to diamond solid elements.

Wood is a material that is easy to process various tools. One of their types can be a drill. You have to use a drill when processing material quite often.

Holes to be drilled can be different diameter, as well as deaf or through.

For a small size, a tool for metal is usually used, but for an increased diameter, a specialized drill for wood is used. large diameter.

There are several types:

There are, but rarely used, drills for cutting cone spikes, cork, etc., etc. Let's consider some of them.

Twisted, or single-stranded

A spiral, or screw, wood drill is available with two types of working tips: conical and special cutters. The basis is a cylindrical rod, the working part of which is formed by helical spiral grooves. Grooves effectively remove chips during operation.

Used for making deep holes. Holes with this tool are even, smooth and neat.

ballerina

It is an adjustable device with incisors. The gimlet in the center performs pre-drilling, and the cutters cut along the circumference. When setting desired diameter the cutters move along the guide at the same distance from the gimlet and are securely fixed.

Due to the design features deep holes cannot be made. The maximum hole size does not exceed 300 millimeters.

Crown

Used for drilling shallow through holes. A disk is used as the basis, in the center of which a spiral gimlet is installed. Saw blades are installed in special places. Usually produced in sets with canvases of different sizes up to 100 mm.

Forstner drill for wood

The Forstner drill is mainly used for furniture production, for drilling holes of exact diameter. It allows you to easily make a blind hole. Blades are available in different diameters working surface: 10, 16, 24, 27, 32, 36, 38, 40, 45, 50 (mm). The price depends on the diameter, the larger it is, the greater the price.

It is a drill consisting of a cylindrical shank with two cutting edges and a circumferential edge. The cutter is ideally characterized smooth edges holes and long service life.

Fountain drill

For drilling any kind of wood, quite often, feather drills are used.

The feather drill is designed to make through holes of different diameters. Of course, you can drill with other types of drills, but The advantage of a pen drill is as follows:

• low price;
• good diameter selection step;
• ease of use, no pre-drilling required;
• high performance;
• the possibility of using an extension cord.

The disadvantages include the quality of work and rather rapid wear of the cutting parts, and therefore are usually used for rough operations that do not require surface cleanliness.

What is a drill?

Structurally, the drill is made in the form of a rod. Top part The rod is a hexagon designed to be clamped into the drill head. The lower part, working, has the form of a blade, in which two cutting blades are sharpened on the sides special form. Thanks to this shape, the blade cuts into the wood, removing chips in a circle. In order for the drill to be stable during operation, a centering tip is made in its very center below the blade.

By their appearance, drills can be one-sided and two-sided. The bevel angle of the cutter, for one-sided is 70-90 degrees, and for double-sided 115-135 degrees.

The drill has a standard length of 150 mm. Using a special extension cord, the depth can be increased up to thirty centimeters.

So, The following parts of the tool can be distinguished:

At points of sale, you can purchase both a set of drill bits for wood and single ones. They are produced different sizes diameter. A number is indicated on the blade indicating the diameter of the hole in millimeters that it can perform, for example, 50. The maximum diameter used is sixty millimeters. No longer produced, as the tool will simply break under such a load. The most popular set consists of diameters: 10, 12, 16, 18, 20, 25 (mm).

The tool is distinguished by color:

• Golden. The material was treated with internal pressure relief.
• Dark. Heated steam treatment was carried out to increase the strength of the material.
• Bright gold. The surface is coated with titanium nitride, which increases the service life of the tool.
• Steel. No additional processing.

Features of use

It is better to use such a drill with a drill that has speed control. They must be set to medium mode, since when working at high speeds, the probability of drill breakage increases. It should be noted that the larger the diameter of the drill, the lower the rotation speed should be set.

During operation, the middle of the drill must be set strictly perpendicular to the workpiece being processed, the pressing force is small. The chips that appear in the created hole, due to the design of the drill, must be periodically removed. If this is not done, it will become impossible to control the drilling process, and the load on the drill and tool will also increase.

I would like to highlight such an interesting tool as an adjustable drill bit. This tool allows you to make holes with a diameter of 22 to 76 mm. Such a device is very convenient to use for non-standard diameters, for example, 23 mm, 52 mm, etc. Work is exclusively carried out at low rotation speeds, with power tools.

How to sharpen a drill bit?

As mentioned above, the disadvantage of a pen tool is the rapid wear of the cutting edges, but at the same time it is not difficult to sharpen them yourself.

Any abrasive material can be used for sharpening. You can sharpen by hand or on a machine. It is best to sharpen the cutters according to the pattern, and try to grind the tip in the center. When sharpening a pen drill for woodworking, you must be very careful not to accidentally damage this tip.

After finishing the sharpening process, it is necessary to carry out test drilling and, if necessary, correct cutting blades or centering.

Summing up, it should be noted: the choice of a tool will primarily depend on the requirements for the quality of work when processing the material, as well as technological conditions. For one-time work, you can use a cheap tool, while for permanent work it is better to use drills produced well-known manufacturers Bosch, Makita, DeWalt, Heller. They are made from quality materials which will ensure a clean cut and a longer service life.

All photos from the article

Often, when working with wood, it becomes necessary to drill holes different diameter. To do this, there is a whole arsenal of devices, which, as a rule, are united by the common name of a crown on a tree. Nevertheless, professionals divide them into several directions, for example, a 110 mm wood crown can be not only a crown as such, but also a core cutter, and in order to reduce these errors, we will try to sort out the assortment.

The most common fixtures

All devices of this type are made of durable tool steel. The denser the mass, the stronger the cutting edge must be. Any instrument other than cutting edge necessarily has a working part and a clamping shank.

Twist drills

This is a classic type of tool, almost everyone is familiar with them, it is this type that any person means by the concept of a drill. The range for wood processing here ranges from 3 to 52 mm.

Interestingly, products with a diameter of up to 10 mm are made smooth. But already everything that goes above often has a hex clamping shank. It is necessary, because the load during drilling increases many times and the tool is able to rotate in the chuck.

Important: all the lineup, except for a core cutter, designed for working with wood can be distinguished by the presence of a sharp guide shank.
It enters the array first and prevents the tool from slipping or moving to the side.

When working with such nozzles great importance has the number of revolutions set on the drill, if these parameters are neglected, then in best case you will not be able to drill a hole, in the worst case, you can “burn” the drill at high speeds when overheated, or even break it.

• So small drills, the diameter of which does not exceed 14 mm, on soft wood work best at 1800 rpm.. If you have to work with hard wood, then the number of revolutions is reduced to 750.

• The average diameter of the tool is considered from 16 mm to 25 mm. For this direction, experts recommend exhibiting on soft wood 1500rpm Hard material is drilled at 500 rpm.
• Starting from the upper threshold of the average diameter and ending maximum dimensions in 52 mm, work should be done at 500 rpm for soft material and at 250 rpm on a hard.

The length of the working surface of the drill is also different. Here everything directly depends on the diameter of the tool, the thicker the drill, the longer it can be. The minimum length is 80 mm, the maximum is limited to 600 mm.

In addition, it would be useful to observe a reasonable ratio between the diameter of the cutting surface, the size of the drill and the power of the drill itself. So, for example, a fifty-millimeter drill 60 cm long will weigh about 3 kg and not every drill is able to turn it even at idle.

Fountain drills

This is a rather specific tool, the dimensions of the holes that can be made with their help range from 10 to 55 mm. Their main advantage lies in the simplicity of design and low cost. The price for pen models is 10 times lower than for twist drills.

But they have a serious disadvantage. Fountain drills are quite problematic to drill deep hole, this is due to the fact that a chip removal mechanism is not provided. In fact, it is a flat, multidirectionally sharpened knife with a guide spike in the middle.

All models of this type have a hexagonal shank, this is caused by a large load during operation.

Most often, such a tool is used to work with a thin board, plywood, as well as with chipboard boards, USB or hardboard.

• As for the number of revolutions, they are higher here than with the spiral options. So feather nozzles with a diameter of up to 25 mm, on soft wood, work at 2000 rpm. hard material processed at 1500 rpm.
• Accordingly, wide nozzles of 30 - 55 mm are drilled on soft material at 1500 revolutions. For hard rock should be set to no more than 1000 rpm.

1. Design features
2. Preparation for work
3. Models
4. DeWalt
5. Bosch

The ring cutting method is used to form holes of large diameter. Used for work hand power tool, an annular nozzle on a drill . One of the types of annular drills is a crown for wood.

Scope of use, main characteristics

Wood crowns are designed for cutting through holes, most often used to provide a seat for a socket. With their help, using a nozzle with a certain coating, they process wood, chipboard, plywood, concrete, plastic, metal.

Samples with a diameter of 68 mm are suitable for many types of work.

Core drills up to 65 mm wide are equipped with a 19 mm shank. Samples bigger size - fastener 32 mm in diameter. The number of toothed segments on the ring depends on the drill bit size. On average, hole saws have between 2 and 16 teeth.

Hole drills are also used to form a clean cut with a smooth inner surface groove. After work, it is not necessary to modify the workpiece, remove burrs, since they do not form. Before cutting holes, there is no need to pre-center, drill the surface to be treated. As a result, the time of work is reduced, the quality increases. It is possible to drill holes without dust, noise. The hole cutter provides comfortable work.

Design features

Regardless of what material the crown is intended for processing, it includes several mandatory elements. Consists of a cutting head, a shank and a pilot drill with a pointed end. The kit also includes a hexagon, with which the drill is clamped in the chuck.

The cutting head is produced in the form of a solid cylindrical edge with sharp teeth or as a collapsible design with a round seat into which a cutting ring of the required diameter is inserted.

The ring after installation in the socket does not close, it has the configuration of a cut cylinder. Usually they purchase a working tool with a set of cutters of various diameters and one shank.

Type-setting rings allow you to make grooves of a certain size, change nozzles. Each hole cutter has characteristic slots or holes: through them, chips are ejected, removed wooden cork. On samples of large diameter, the technological holes are located on top, on smaller models - on the side.

At self-manufacturing crown nozzle is used metal pipe required diameter.

Preparation for work

Technological hole on the cup has irregular shape, which prevents the nozzle from turning in the socket. It is recommended to tighten the clamping nut tightly so that when drilling grooves in wood with a high load, the ring crown does not loosen.

After center drill and the cutting nozzle are tightly fixed in their seats, the chuck is installed in a hand-held power tool, drilling begins. The hole is cut strictly perpendicular.

Before work, the number of revolutions is set on the drill. Each additional millimeter to the groove diameter increases the vibration of the tool. Therefore, you should choose drills with high power, comfortable handle.

For soft wood, 300 rpm is enough; for hard wood, it is better to set the regulator of a drill or rotary hammer at around 500 rpm. Sharpening of crowns is carried out in workshops or at home.

Models

Overview of some drills.

bison

The Zubr company produces crowns for wood with centering drills made of high-tech tool steel. The center drill provides increased rigidity in softwood and hardwood applications. Crowns are installed on an ordinary household drill, suitable for working with wood, plastic, plywood, chipboard, MDF, drywall.

DeWalt

Crowns are used to form grooves, holes when performing electrical installation, laying communication lines. Bimetallic products do not dull for a long time, even when in contact with nails, fittings, they are hardy.

Bosch

Crowns are hardy, do not overheat, do not deform during sawing, withstand a large number of drilling cycles without resharpening.

The table shows the sizes, prices for crowns of various types.