The work of drilling holes in metal, depending on the type of holes and the properties of the metal, can be performed with different tools and using various tricks. We want to tell you about drilling methods, tools, as well as safety precautions when performing these works.

Drilling holes in metal may be needed during repairs engineering systems, household appliances, car, creating structures from sheet and profile steel, designing crafts from aluminum and copper, in the manufacture of circuit boards for radio equipment, and in many other cases. It is important to understand what kind of tool is needed for each type of work so that the holes are the right diameter and in a strictly intended place, and what safety measures will help to avoid injury.

Tools, fixtures, drills

The main tools for drilling are manual and electric drills, and, if possible, drilling machines. The working body of these mechanisms - the drill - can have a different shape.

There are drills:

spiral (most common);
screw;
crowns;
conical;
feathers, etc.

Drill production various designs standardized by numerous GOSTs. Drills up to Ø 2 mm are not marked, up to Ø 3 mm - the section and steel grade are indicated on the shank, larger diameters may contain additional information. To obtain a hole of a certain diameter, you need to take a drill a few tenths of a millimeter smaller. The better the drill is sharpened, the smaller the difference between these diameters.

Drills differ not only in diameter, but also in length - short, elongated and long are produced. important information is the ultimate hardness of the metal being processed. The shank of the drills can be cylindrical and conical, which should be borne in mind when selecting a drill chuck or adapter sleeve.

1. Drill with a cylindrical shank. 2. Tapered shank drill. 3. Drill with a sword for carving. 4. Center drill. 5. Drill with two diameters. 6. Center drill. 7. Conical drill. 8. Conical multi-stage drill

For some work and materials, special sharpening is required. The harder the metal being processed, the sharper the edge must be sharpened. For thin sheet metal, a conventional twist drill may not be suitable, you will need a tool with a special sharpening. Detailed recommendations for various types drills and processed metals (thickness, hardness, hole type) are quite extensive, and in this article we will not consider them.

Various types of drill sharpening. 1. For hard steel. 2. For stainless steel. 3. For copper and copper alloys. 4. For aluminum and aluminum alloys. 5. For cast iron. 6. Bakelite

1. Standard sharpening. 2. Free sharpening. 3. Diluted sharpening. 4. Heavy sharpening. 5. Separate sharpening

To fix parts before drilling, a vice, stops, conductors, corners, clamps with bolts and other devices are used. This is not only a safety requirement, it is actually more convenient, and the holes are of better quality.

To chamfer and process the surface of the channel, they use a countersink of a cylindrical or conical shape, and to mark a point for drilling and so that the drill does not “jump off” - a hammer and a center punch.

Advice! The best drills until now, they are considered to be issued in the USSR - exact adherence to GOST in geometry and metal composition. German Ruko with titanium coating are also good, as well as drills from Bosch - proven quality. Good feedback about Haisser products - powerful, usually with a large diameter. The Zubr drills, especially the Cobalt series, proved to be worthy.

Drilling modes

It is very important to correctly fix and guide the drill, as well as select the cutting mode.

When making holes in metal by drilling, important factors are the number of revolutions of the drill and the feed force applied to the drill, directed along its axis, providing the penetration of the drill at one revolution (mm / rev). When working with various metals and drills are recommended various modes cutting, and the harder the metal being processed and the larger the diameter of the drill, the lower the recommended cutting speed. An indicator of the correct mode is a beautiful, long chip.

Use the tables to choose the right mode and not dull the drill prematurely.

Feed S 0 , mm/rev	Drill diameter D, mm
	2,5	4	6	8	10	12	146	20	25	32
	Cutting speed v, m/min
*When drilling steel*
0,06	17	22	26	30	33	42	—	—	—	—
0,10	—	17	20	23	26	28	32	38	40	44
0,15	—	—	18	20	22	24	27	30	33	35
0,20	—	—	15	17	18	20	23	25	27	30
0,30	—	—	—	14	16	17	19	21	23	25
0,40	—	—	—	—	—	14	16	18	19	21
0,60	—	—	—	—	—	—	—	14	15	11
*When drilling cast iron*
0,06	18	22	25	27	29	30	32	33	34	35
0,10	—	18	20	22	23	24	26	27	28	30
0,15	—	15	17	18	19	20	22	23	25	26
0,20	—	—	15	16	17	18	19	20	21	22
0,30	—	—	13	14	15	16	17	18	19	19
0,40	—	—	—	—	14	14	15	16	16	17
0,60	—	—	—	—	—	—	13	14	15	15
0,80	—	—	—	—	—	—	—	—	—	13
*When drilling aluminum alloys*
0,06	75	—	—	—	—	—	—	—	—	—
0,10	53	70	81	92	100	—	—	—	—	—
0,15	39	53	62	69	75	81	90	—	—	—
0,20	—	43	50	56	62	67	74	82	-	-
0,30	—	—	42	48	52	56	62	68	75	—
0,40	—	—	—	40	45	48	53	59	64	69
0,60	—	—	—	—	37	39	44	48	52	56
0,80	—	—	—	—	—	—	38	42	46	54
1,00	—	—	—	—	—	—	—	—	—	42

Table 2. Correction factors

Table 3. Revolutions and feeds for various drill diameters and drilling in carbon steel

Types of holes in metal and methods for drilling them

Types of holes:

deaf;
through;
half (incomplete);
deep;
large diameter;
for internal thread.

Threaded holes require the determination of diameters with tolerances established in GOST 16093-2004. For common hardware, the calculation is given in table 5.

Table 5. The ratio of metric and inch threads, as well as the selection of the hole size for drilling

Metric thread				Inch thread				Pipe thread
Thread diameter	Thread pitch, mm	Thread hole diameter		Thread diameter	Thread pitch, mm	Thread hole diameter		Thread diameter	Thread hole diameter
Thread diameter	Thread pitch, mm	min.	Max.	Thread diameter	Thread pitch, mm	min.	Max.	Thread diameter	Thread hole diameter
M1	0,25	0,75	0,8	3/16	1,058	3,6	3,7	1/8	8,8
M1.4	0,3	1,1	1,15	1/4	1,270	5,0	5,1	1/4	11,7
M1.7	0,35	1,3	1,4	5/16	1,411	6,4	6,5	3/8	15,2
M2	0,4	1,5	1,6	3/8	1,588	7,7	7,9	1/2	18,6
M2.6	0,4	2,1	2,2	7/16	1,814	9,1	9,25	3/4	24,3
M3	0,5	2,4	2,5	1/2	2,117	10,25	10,5	1	30,5
M3.5	0,6	2,8	2,9	9/16	2,117	11,75	12,0	—	—
M4	0,7	3,2	3,4	5/8	2,309	13,25	13,5	11/4	39,2
M5	0,8	4,1	4,2	3/4	2,540	16,25	16,5	13/8	41,6
M6	1,0	4,8	5,0	7/8	2,822	19,00	19,25	11/2	45,1
M8	1,25	6,5	6,7	1	3,175	21,75	22,0	—	—
M10	1,5	8,2	8,4	11/8	3,629	24,5	24,75	—	—
M12	1,75	9,9	10,0	11/4	3,629	27,5	27,75	—	—
M14	2,0	11,5	11,75	13/8	4,233	30,5	30,5	—	—
M16	2,0	13,5	13,75	—	—	—	—	—	—
M18	2,5	15,0	15,25	11/2	4,333	33,0	33,5	—	—
M20	2,5	17,0	17,25	15/8	6,080	35,0	35,5	—	—
M22	2,6	19,0	19,25	13/4	5,080	33,5	39,0	—	—
M24	3,0	20,5	20,75	17/8	5,644	41,0	41,5	—	—

through holes

Through holes penetrate the workpiece completely, forming a passage in it. A feature of the process is the protection of the surface of the workbench or tabletop from the exit of the drill beyond the workpiece, which can damage the drill itself, as well as provide the workpiece with a “burr” - a hart. To avoid this, use the following methods:

use a workbench with a hole;
put a gasket made of wood or a “sandwich” under the part - wood + metal + wood;
put a metal bar under the part with a hole for the free passage of the drill;
reduce the feed rate last step.

The latter method is mandatory when drilling holes "in place" so as not to damage closely spaced surfaces or parts.

Holes in thin sheet metal are cut with spatula drills, because the twist drill will damage the edges of the workpiece.

blind holes

Such holes are made to a certain depth and do not penetrate the workpiece through and through. There are two ways to measure depth:

limiting the length of the drill with a sleeve stop;
limiting the length of the drill with an adjustable stop chuck;
using a ruler fixed on the machine;
a combination of methods.

Some machines are equipped with an automatic feed to a given depth, after which the mechanism stops. During the drilling process, it may be necessary to stop the work several times to remove the chips.

Holes of complex shape

Holes located on the edge of the workpiece (half) can be made by connecting two workpieces or a workpiece and a gasket with faces and clamping with a vise and drilling a full hole. The gasket must be made of the same material as the workpiece being processed, otherwise the drill will “leave” in the direction of least resistance.

A through hole in the corner (shaped rolled metal) is performed by fixing the workpiece in a vice and using a wooden gasket.

It is more difficult to drill a cylindrical workpiece tangentially. The process is divided into two operations: preparation of a platform perpendicular to the hole (milling, countersinking) and drilling itself. Drilling holes in surfaces located at an angle also begins with the preparation of the site, after which a wooden gasket is inserted between the planes, forming a triangle, and a hole is drilled through the corner.

Hollow parts are drilled, filling the cavity with a cork made of wood.

Stepped holes are produced using two techniques:

Reaming. The hole is drilled to the full depth with a drill of the smallest diameter, after which it is drilled to a given depth with drills with diameters from smaller to larger. The advantage of the method is a well-centered hole.
Reducing the diameter. A hole of maximum diameter is drilled to a given depth, then the drills are changed with a successive decrease in diameter and a hole deepening. With this method, it is easier to control the depth of each step.

1. Drilling a hole. 2. Diameter reduction

Large diameter holes, annular drilling

Obtaining holes of large diameter in massive workpieces, up to 5-6 mm thick, is a laborious and costly business. Relatively small diameters - up to 30 mm (maximum 40 mm) can be obtained using cone, and preferably step-cone drills. For holes with a larger diameter (up to 100 mm), hollow bi-metal hole saws or hole saws with carbide teeth with a center drill will be required. Moreover, the craftsmen traditionally recommend Bosch in this case, especially on hard metal, such as steel.

Such annular drilling is less energy-intensive, but may be more financially costly. In addition to drills, the power of the drill and the ability to work at the lowest speeds are important. Moreover, the thicker the metal, the more you want to make a hole on the machine, and with a large number of holes in a sheet with a thickness of more than 12 mm, it is better to immediately look for such an opportunity.

In a thin-sheet blank, a large-diameter hole is obtained using narrow-toothed crowns or a milling cutter mounted on a grinder, but the edges in the latter case leave much to be desired.

Deep holes, coolant

Sometimes a deep hole is required. In theory, this is a hole whose length is five times the diameter. In practice, deep drilling is called, requiring forced periodic removal of chips and the use of coolants (cutting fluids).

In drilling, coolants are needed primarily to reduce the temperature of the drill and workpiece, which are heated by friction. Therefore, when making holes in copper, which has a high thermal conductivity and is itself capable of removing heat, coolant can be omitted. Cast iron is drilled relatively easily and without lubrication (except for high-strength ones).

In production, industrial oils, synthetic emulsions, emulsols and some hydrocarbons are used as coolants. In home workshops you can use:

technical vaseline, castor oil - for mild steels;
laundry soap - for aluminum alloys of the D16T type;
a mixture of kerosene with castor oil - for duralumin;
soapy water - for aluminum;
turpentine diluted with alcohol - for silumin.

The universal coolant can be prepared independently. To do this, you need to dissolve 200 g of soap in a bucket of water, add 5 tablespoons of machine oil, you can use it, and boil the solution until a soapy homogeneous emulsion is obtained. Some masters use lard to reduce friction.

Processed material	Coolant
Steel:
carbonaceous	Emulsion. Sulfurized oil
structural	Sulfurized oil with kerosene
instrumental	Blended oils
alloyed	Blended oils
Ductile iron	3-5% emulsion
Cast iron	Without cooling. 3-5% emulsion. Kerosene
Bronze	Without cooling. Blended oils
Zinc	Emulsion
Brass	Without cooling. 3-5% emulsion
Copper	Emulsion. Blended oils
Nickel	Emulsion
Aluminum and its alloys	Without cooling. Emulsion. Mixed oils. Kerosene
Stainless, high temperature alloys	Mixture of 50% sulfurated oil, 30% kerosene, 20% oleic acid (or 80% sulfofresol and 20% oleic acid)
Fiber, vinyl plastic, plexiglass and so on	3-5% emulsion
Textolite, getinaks	Compressed air blowing

Deep holes can be made by solid and annular drilling, and in the latter case, the central rod formed by the rotation of the crown is broken out not entirely, but in parts, weakening it with additional holes of small diameter.

Solid drilling is performed in a well-fixed workpiece with a twist drill, through the channels of which coolant is supplied. Periodically, without stopping the rotation of the drill, it is necessary to remove it and clean the cavity from chips. The work with a twist drill is carried out in stages: first, a short hole is taken and a hole is drilled, which is then deepened with a drill of the appropriate size. With a significant depth of the hole, it is advisable to use guide bushings.

With regular drilling of deep holes, it can be recommended to purchase a special machine with automatic coolant supply to the drill and precise centering.

Drilling by marking, template and jig

You can drill holes according to the markings made or without it - using a template or a jig.

Marking is done with a punch. A hammer blow marks a place for the tip of the drill. A felt-tip pen can also mark a place, but a hole is also needed so that the tip does not move from the intended point. The work is carried out in two stages: preliminary drilling, hole control, final drilling. If the drill "left" from the intended center, notches (grooves) are made with a narrow chisel that guide the tip to a given place.

To determine the center of a cylindrical workpiece, a square piece of tin is used, bent at 90 ° so that the height of one shoulder is approximately one radius. Applying a corner from different sides of the workpiece, draw a pencil along the edge. As a result, you have an area around the center. You can find the center by the theorem - the intersection of perpendiculars from two chords.

A template is needed when making a series of parts of the same type with several holes. It is convenient to use it for a pack of thin-sheet blanks connected with a clamp. This way you can get several drilled blanks at the same time. Instead of a template, a drawing or diagram is sometimes used, for example, in the manufacture of parts for radio equipment.

The conductor is used when the accuracy of maintaining the distances between the holes and the strict perpendicularity of the channel are very important. When drilling deep holes or when working with thin-walled tubes, in addition to the conductor, guides can be used to fix the position of the drill relative to the metal surface.

When working with a power tool, it is important to remember human safety and prevent premature wear of the tool and possible marriage. In this regard, we have collected some useful tips:

Before work, you need to check the fastening of all elements.
Clothing when working on a machine or with an electric drill should not be with elements that can fall under the action of rotating parts. Protect your eyes from chips with goggles.
The drill, when approaching the surface of the metal, must already rotate, otherwise it will quickly become dull.
It is necessary to remove the drill from the hole without turning off the drill, reducing the speed if possible.
If the drill does not go deep into the metal, then its hardness is lower than that of the workpiece. Increased hardness in steel can be detected by running a file over the sample - the absence of traces indicates increased hardness. In this case, the drill must be selected from a carbide with additives and work at low speeds with a small feed.
If a small diameter drill does not fit well in the chuck, wind a few turns of brass wire around its shank, increasing the gripping diameter.
If the surface of the workpiece is polished, put a felt washer on the drill to ensure that it does not scratch even when it comes into contact with the drill chuck. When fastening workpieces made of polished or chrome-plated steel, use spacers made of fabric or leather.
When making deep holes, a rectangular piece of foam placed on a drill can serve as a measuring instrument and at the same time blow off small chips while rotating.

Today everyone has home master available essential tool for metal cutting, drilling, stripping. But what if you need to drill a large hole? After all, the maximum cross section of a conventional drill for a hand-held electric drill is only 20 mm.

Tools for drilling large holes

There are several ways to drill a hole with a diameter of more than 20 mm. For this, special devices are used:

Cone drill. A large number of openings of the same size will not work. But for home use quite acceptable. The maximum section is up to 40 mm. The thickness of the processed metal is 5-6 mm.
Cone step drill. It is more convenient to use, since each of its steps is formed by a smooth spiral transition. When drilling, this makes it easy to track the actual diameter of the hole. With it, you can drill a circle up to 40 mm in diameter on metal up to 6 mm thick.
Bimetal crowns - suitable for preparing holes up to 109 mm in steel products up to 5 mm thick. When working, it is strongly recommended to use specialized lubricants and coolants, which will ensure maximum service life. cutting tool. Also, an adapter is required to install the device on an electric drill. On average, 5-20 openings can be drilled with a bimetallic crown, depending on its quality, which, accordingly, is reflected in the cost.

How can you drill a large hole at no extra cost?

For this method, you will need a small section drill (5-6 mm is enough), as well as a milling cutter or a used grinding wheel (corresponding or slightly smaller diameter holes) for the grinder. The option is more laborious, so it takes much more time.

2 circles are marked on a metal blank with a pencil:

1 - for the future hole.
2 - depends on the cross section of the drill, that is, when using a 6 mm tool, the diameter of the intended circle will be 6 mm less than the previous one.

On the 2nd circle, it is necessary to punch 2 places in opposite places and drill holes with a 6 mm drill. From the received openings along the intended line, you need to retreat about 3 mm and again mark the places for drilling. Holes are drilled along the contour of the entire circle. If necessary, the remaining sections can be chopped with a chisel.

The hole will be jagged, so it needs to be bored out. This can be done with an electric drill with a milling cutter, but it is much more convenient with a grinder using grinding abrasive wheels of a suitable diameter. With a grinder, you can quickly and evenly bore a hole to the required diameter.

Therefore, you should not throw away used abrasive wheels for a grinder with a diameter of even less than 45 mm - they can always come in handy on the farm.

What to drill big hole in metal

Now drilling large diameter holes in metal is not serious problem . The main thing is to prepare well. Let's say you need to make a hole in a corner, channel or mortgage to strengthen building structure or hang a shelf, lamp or piping. That is, to carry out this not in the conditions of a workshop or workshop, but directly on the spot. The easiest way to drill in such conditions is to use an electric drill. But, imagine how much pressure you need to apply to it in order to drill a hole with a diameter of 16 or 20 mm? The question is not rhetorical - the effort will be about 40-50 kgf. This is not at all easy to ensure if the intended hole is located above the shoulder level of the driller. Even 10 years ago, when such a task arose, even professionals resorted to autogen and, just imagine, to drilling small holes around the circumference of a large one. Today, there is a completely professional solution for this - core drilling, which ensures the production of holes according to 11 grades.

However, many are sure that core drilling is a rather expensive method, economically viable only with industrial volumes. Is such a statement true? Partly. To date, you can choose from several options for tools and equipment for drilling holes in metal of large diameter without reaming. At the same time, the cost per hole will be justified even when drilling only a few holes.

Consider, what tool options for drilling through holes of large diameter in metal does the market offer. For comparison, we take a diameter of 51 mm.

First, this bimetallic crowns. The choice includes samples from the cheapest ones, which are immediately sold in sets and cannot be accepted by us in this review for the reason that their purpose is to drill wood, and if they manage to drill a sheet of metal, then it will be no thicker than 0.5 mm . At a price of 240 rubles, products with a wall thickness of 1-1.2 mm start, often it is marked HSS - Co 5% and even HSS - Co 8, but judging by the fact that drilling one hole in stainless steel takes more than one such crowns, cobalt is probably not there at all. twice as expensive crowns of more decent quality, really allowing you to drill stainless steel and ordinary steel a few millimeters thick. Bimetal crowns of this level allow you to drill 5-20 holes in a steel sheet with a thickness of 5 mm. At the same time, the use of any lubricating-cooling composition ensures that the upper bar of this range is reached. On the third step there are bimetallic crowns worldwide famous brands, which are twice as expensive, can be equipped with special devices for quick change in a drill, but in terms of resource, they do not much or do not exceed the average price level at all.

Drilling large holes in steel sheets more than 5-6 mm thick for bimetallic crowns is a great difficulty, although sometimes you can hear a different opinion. It is based on data on the total drilling depth of such crowns - 35-38 mm. As a rule, only sellers of bimetallic crowns, who do not have a more worthy tool in their assortment, risk advising to drill a 30 mm sheet or beam in this way. The fact is that the bimetallic crown is devoid of a chip removal groove, and as soon as the thickness of the drilled metal becomes greater than the height of the tooth of the crown, problems with chip removal begin. In addition, the body of the bimetallic crown is not quite cylindrical, which causes jamming in the metal of solid thickness.

Unlike bimetallic crowns, crowns with carbide teeth provide more precise drilling. The body of the carbide hole saw is chiselled, while the bi-metal hole saw is rolled from a band and welded into a ring. There are several types of carbide drill bit designs. Without delving into the types of shanks and types of attachment, we will analyze only the cutting part. The most expensive part of the crown is the carbide teeth. The quality of the material greatly affects the drilling speed, impact resistance, bit life and the ability to drill alloyed steels with a high chromium content.

The second feature that you need to pay attention to is the shape of the tooth and its size. For drilling thin sheet steel, thin stainless steel and non-ferrous metals, a narrow tooth with a flat profile, slightly beveled inward, is used. Such crowns also do not have a chip-removing groove, and they will not be able to drill metal thicker than the height of their tooth. The price of such drill bits is two to three times higher than that of bimetallic drill bits, depending on the design of their body, they can be designed for drilling flat materials or for drilling pipes and profiles. Since these are professional samples, fakes are not common at present, and almost all samples found on the market are of acceptable quality, but excellent quality should be chosen from manufacturers specializing in these products.

Thicker metal can be drilled with crowns with teeth of a variable sharpening profile. In such crowns, every second or, as a rule, one of three consecutive carbide teeth is sharpened in its own way. This provides soft cutting, no vibration, reduced load on the cutting edges and, as a result, an increase in the resource of the crown. In such crowns, there is a short or long chip removal groove, almost the entire height of the wall. The first version of the drill bits allows you to drill metal up to 12 mm thick, and more powerful drill bits with a developed chip removal groove - up to 25 mm. It is this version of the tool for drilling holes in large diameter metal that is the most progressive, providing the best performance and quality. The price of such crowns is 20-30% higher than that of thin-walled ones and in absolute terms is 1880-1910 rubles, as we agreed, for a crown with a diameter of 51 mm. As elsewhere in nature, there are deviations in one direction or another up to 2 times, but, as usual, to consider builds a golden mean.

A variant in which the metal is quite thick, say 10 mm, and the hole diameter is 20-25 mm can be solved with a carbide hole saw with a pilot drill. Recommended as a drive drilling machine on a magnetic base. but you can also use an electric drill. With the mentioned machine, investments will amount to 21,164 rubles without VAT, and with a drill - 5,000 - 5,500 thousand.

For a hole with a diameter of 50-60 mm, with such a metal thickness, the use of a magnetic or stationary drilling machine is clearly required. A large load causes a high cost of investing in equipment, and together with a crown it will be about 56,000 rubles, or, with a magnetic stand of a drilling machine and a separately purchased drill, about 50,000. Drilling such holes with a drill from your hands is not only difficult, but also dangerous .

Drilling large-diameter holes in metal up to 5 mm thick with a hand-held electric drill is not difficult when using both bi-metal and carbide drill bits. The choice of tool is made depending on the required accuracy. When drilling holes with a bimetallic crown, the ovality of the holes and the increase in diameter from the desired one can reach 4% or in absolute terms - 2 - 3 mm. When drilling with a carbide crown - only 0.6 - 1 mm. In addition, all carbide drill bits presented in the review, and almost all metal drill bits available on the market, also drill stainless steel.

Drilling holes in metal - tools and fixtures

Metal processing is carried out not only in industrial conditions. While doing repair work on a car, making structures on a personal plot or carrying out repairs to a home, it is necessary to drill holes in the metal. At home, a hand drill is most often used.
This universal tool requires certain skills to work with solid products. You can purchase or make your own machine for drilling holes in metal, but this is not a cheap pleasure.

The technology of drilling holes in metal consists in removing a thin layer of material due to the simultaneous translational and rotational movement of the drill.

The main condition for high-quality and safe (for the tool) processing is holding the chuck axis in a fixed position. With the help of the machine it is easy to maintain straightness, which cannot be said when working with a hand tool.

If you are not sure about the firmness of your hands (this is normal for ordinary person), drilling at a right angle requires mechanical assistants (jigs).

Immediately make a reservation that additional conductors are required only when the thickness of the metal exceeds the diameter of the drill.

If you're making a hole in a thin steel plate, straightness doesn't matter.

Fixtures for drilling perpendicular holes

There are several types of hand drill guides. Power tools are not well suited for metal work, especially when it comes to precision.

Drilling guide. Made in the form of a body, easy to hold, inside of which there are guide bushings for drills of various diameters.

The material of the sleeves is harder than the tool, so the holes do not wear out. By installing the jig exactly above the center of the intended hole, you don’t have to worry that the drill will “take away” from the given direction.

This device is especially useful when drilling perpendicular holes in pipes of small diameter, when the tip tends to slip off the cylindrical surface.

Drill guide (manual). Support device in which the tool is fixed by the neck

The sole is placed on the workpiece, holding the handle with the second hand. The drill moves strictly vertically, avoiding distortions and drifts of the drill.

The design can have an angle holder for pipes of small diameter, which makes the fixture more versatile.

With a swivel mechanism, you also get a device for drilling holes at an angle.

True, the metal cannot be drilled in this way, lateral loads will quickly break the drill.

Drill stand (semi-stationary). In fact, it is an inexpensive alternative to a drilling machine.

The carriage with a fixed tool (for the same neck) moves along the bar with the help of a lever. The workpiece is firmly held on the sole with a vice or clamp. The quality of drilling is very high, but the cost of the device is considerable. Although in comparison with a drilling machine, it is inexpensive.

A device for holding the drill at a right angle can be made independently. It is enough to drill holes of various diameters in a bar of durable material, for example - textolite or ebonite.

You should not count on lateral support only - it is rather a “device” for visual control. With a lateral deviation, the drill will quickly break the pilot hole in the jig.

The next challenge is deep hole drilling

Technologically correct would be to use lathe. Moreover, when processing cylindrical parts (for example, a gun barrel), the workpiece rotates, while the drill remains stationary. Cooling and forced removal of chips from the hole are mandatory.

To do this, deep-drill drills have special grooves on the surface, or the drill is periodically removed from the workpiece to clear chips.

At home, be sure to use drill guides. Masters recommend not to drill holes deeper than 2/3 of the length of the drill. Ordinary water can be used as cooling, the drill is periodically removed from the hole for cleaning from chips and cooling.

Important! When drilling in several approaches, it is unacceptable to change the angle of the drill. Otherwise, you can "screw up" the workpiece.

The use of special long drills requires special technology.

As soon as the cutting part, together with the retracting edges, hides in the hole, the chips will clog the grooves and block the rotation. Therefore, at the last stage, the extraction of the drill and the cleaning of chips are performed more often.

Drilling large holes in metal

Drilling large holes in metal with a bimetal crown - video

This procedure is even more difficult than deep drilling. Large holes are drilled either with a hole saw (for small thicknesses) or conventional drill in several stages.

The technology is the same as in the phased passage. You push the drill into the hole until you get the right size.

Taper Step Drill Overview and Application Tips - Video

A few more examples of the use of a step drill in everyday life

Drilling with a step drill in metal with a thickness of 10 mm

How to choose a tool for drilling holes, we have dismantled. Now let's talk about general principles metal processing:

The center of the future hole is “pierced” with a center punch. The tip of the drill rests against the hole at the first revolutions. Of course, if there are guides or a conductor, this is not necessary.
For achievement high precision(by diameter) you should choose a drill 0.1-0.3 mm smaller. Due to slight vibration in the chuck, the diameter increases slightly
Use lubricant to reduce friction and cool. Plain water or machine oil will do
At the first sign of a dull drill, stop work and sharpen the edges. Otherwise, you can not only lose the tool, but also ruin the workpiece.
When drilling hollow workpieces (pipes, boxes), it is advisable to place a wooden spacer inside the workpiece
For drilling blind holes, a stop ruler with markings is used. If your drill is not equipped with a stop, wrap the indicator ring around the drill with light tape.

An interesting video on the topic: How to drill square hole in metal

Alexander | 24.04.2017 11:09

An overview of conical step drills and tips for their use.
Very poor review. There are no recommendations for use.
These drills must be operated at low speeds. About 200.
At high speeds (from 400 and above), they "lick" and become unusable.
These drills are designed more for cold-rolled sheet metal up to 3 mm.

sports | 24.04.2017 14:50

Hello, Alexander. As I understand it, you are talking about a video review of conical stepped drills? For the topic itself is much broader. Thank you for your comment. Let's pick a more interesting review.

How to make a big hole in metal

Large hole in metal

If you have a need to drill large diameter holes, do not rush to spend money on a tool. Consider all options. It is possible that the tool that is suitable in one case is completely useless in another.

Cone drill

The drill is more suitable for home use. Because drilling a large number of holes of the exact diameter will be very difficult.

In this case, it is better to use a cone step drill.

Taper step drill

The most popular drills with a diameter of 0t 6 to 30 mm. (less often up to 40 mm.) with a step of 2 mm. That is, 6, 8, 10, 12 mm. etc.
Typically used for drilling sheet metal up to 2mm thick. and plastic up to 5 mm thick. Undeniable dignity this drill is that for 1500 ─ 3000 rubles. you buy about 10 ─ 15 diameters.

If, when drilling plastic, the drill behaves very well, then drilling holes of large diameters in metal is associated with some difficulties:
with large volumes of work, a 6 mm drill quickly becomes dull;
drilling holes of large diameters requires considerable physical effort.

Crown for metal

Large holes in metal, plastic, wood, etc. with a diameter of 19 to 102 mm. it is convenient to do it with a Hilti bi-metal crown.

The drill bits performed very well when drilling a large number of holes for fittings in metal boxes for cable (metal thickness 2 mm.).

A clear plus is that the crown is collapsible. If the center drill becomes dull or breaks, the replacement price is about 250 rubles.

But for each diameter, you will have to use a separate crown, the price of which (depending on the diameter) is from 400 to 1200 rubles. Add here 1000 rubles. to the adapter.

Hole press

The tools discussed above, for drilling large holes in metal, have one significant drawback: a very sharp edge. When laying cable or wires without fittings, this can be a serious problem.

To get a perfectly smooth edge, it is better to use a hole press. It costs a little more than 11,000 rubles. But in the set you get 8 nozzles with a diameter of 16.2 to 47 mm.
Without special efforts a large number of holes are punched in metal up to 3 mm thick.

One clarification: the instructions for the PGRO-60 KVT press say that after punching the hole, you need to stop pumping. As practice has shown, it is better to do one more compression with the handles of the press. This makes it easier to remove the cut metal from the matrix.

How to drill metal with a drill - detailed step by step instructions

Drilling metal with a drill is somewhat more difficult than wood, brick or concrete. There are also some features.

For convenience, we have combined practical advice on this type of work into step-by-step instructions.

You will need the following tools: a drill, a drill, coolant (oil is better, but water is also possible), a center punch, a hammer, goggles.
When drilling metal on a horizontal surface, we put a wooden block under the product and fix it as best as possible. When working in a vertical position, rigid fixation is extremely important, since drilling must be strictly perpendicular.
We make markings, after that, using a center punch and a hammer, we outline the center of the future hole.
Pour coolant into a small container.
We put on protective goggles.
We start drilling. Do not exert strong pressure on the drill, because it is better to work at low speeds. If the drill is powerful, then the method of short-term inclusions is suitable, until the tool has had time to gain maximum speed.
Do not forget to cool the drill as often as possible .
When drilling is not strictly perpendicular, but at an angle, it is likely that the drill will jam. If this happens, put the switch in the reverse position. So you avoid injury and do not break the drill.
If everything was done correctly, then even in living conditions using a low-power drill, you can drill a hole in metal with a thickness of up to 5 mm inclusive and a diameter of up to 10-12 mm. More complex tasks will be discussed below.

Metal drilling work

Can you drill metal with a concrete drill?

It is possible, but this is in case of emergency for shallow holes with a small diameter. Unprofitable.

It is better to use either standard metal drills with steel grade R6M5 or improved - R6M5K5.

The letter K in the marking indicates that this is an alloy with the addition of cobalt. On the market you can find a drill, which is called "Cobalt". We will not vouch for all manufacturers, we only note that the reviews on practical application in the vast majority of cases are positive.

How to drill with a step drill for metal?

Step drills are universal - just one can make holes of different diameters (from 2 to 40 mm). They are most effective when working with thin metal, when you need to get a neat edge. They are better fixed in the cartridge, they are easier to sharpen, and therefore, when correct operation last longer, but also cost more than usual. They work with the same principles, but it is easier to drill large diameter holes than with conventional twist drills.

Is it possible to drill metal with a Pobedite drill?

The principle of operation of metal drills is to cut, and crush materials with victorious soldering. Brick, concrete, stone are better suited for this. Therefore, as mentioned above, with a drill for concrete. of course, you can drill metal, but it will quickly become unusable and the victorious soldering will collapse.

What is the larger hole diameter? the lower the turnover should be. The more depth? the gradually you need to reduce the pressure on the drill. With a drill diameter of up to 5 mm, the torque should not be higher than 1200-1500 rpm. Accordingly, 10 mm in diameter - no more than 700 rpm, 15 mm - 400 rpm.

How to drill holes in large diameter metal?

Usually, most of drills for domestic use power from 500 to 800W, which allows you to drill holes with a diameter of up to 10-12 mm. In metal up to 2 mm thick, using step drills, holes up to 40 mm can be made. With a thickness of 3 mm, bimetallic crowns are better suited.

When drilling deep holes with any tool, you may sometimes need a magnet to extract the chips.

metal drilling process

Particular attention should be paid to safety, be sure to take care of your eyes from chips, and if there is a skew and jamming, immediately turn off the drill and rearrange the torque to reverse.

In a power outage or where the noise of an operating tool may disturb others ( read. when can repairs be made so as not to quarrel with neighbors?) - ideal solution when drilling metal will be manual mechanical drill, the so-called rotator. Low speed and pressure, no overheating, just what you need. Of course, there are also disadvantages - the cost of time and fatigue. In such a simple "old-fashioned" way, you can drill holes with a diameter of up to 10 mm.

We hope our advice will be useful to you.

More information in this video.

Drills for metal are selected based on the diameters of the holes and the properties of the material being processed. As a rule, they are made of high-speed steels, such as R6M5K5, R6M5, R4M2. Carbide drills are used to work with cast iron, carbon and alloy hardened steels, stainless steel, and other difficult-to-cut materials.

The power of the electric drill must be designed to drill a hole of the required diameter. Power tool manufacturers indicate the relevant specifications on the product. For example, for drills with a power of 500 ... 700 W, the maximum drilling diameter for metal is 10 ... 13 mm.

There are blind, incomplete, and through holes. They can be used to connect parts to each other by means of bolts, studs, pins and rivets. If the hole is drilled for the purpose of threading, it is worth paying attention Special attention choice of drill diameter. Due to its beating in the cartridge, a breakdown of the hole occurs, which must be taken into account. Indicative data are presented in the table.

To reduce breakdown, drilling is performed in two stages: first with a smaller diameter drill, and then with the main one. The same method of sequential reaming is used when it is necessary to make a hole of a large diameter.

How to drill metal with a drill

The peculiarity of drilling metal with a drill is that it is necessary to manually hold the tool, give it the correct position, and also ensure the required cutting speed.

After marking the workpiece, the center of the future hole should be punched. This will prevent the drill from moving given point. For the convenience of work, the workpiece should be clamped in a bench vise or placed on a stand so that it takes a stable position. The drill is set strictly perpendicular to the surface to be drilled. This is important to avoid damage.

When drilling metal, the drill does not need to exert much pressure. On the contrary, it should decrease as you go. This will prevent breakage of the drill and also reduce burr formation on the trailing edge. through hole. Chip removal should be monitored. If the cutting tool jams, it is released by reverse rotation.

Cutting mode selection

When using a tool made of high speed steel, you can refer to the speed according to the data in the table. When working with carbide drills, the allowable values are 1.5 ... 2 times higher.

drilling metal products needs to be done with refrigeration. If it is not used, there is a high probability that the tool will lose its cutting properties due to overheating. The cleanliness of the surface of the hole in this case will be quite low. An emulsion is usually used as a coolant for hard steels. At home, machine oil is suitable. Cast iron and non-ferrous metals can be drilled without coolant.

Features of deep hole drilling

Holes are considered deep if their size is greater than five drill diameters. The peculiarity of the work here lies in the difficulties associated with cooling and chip removal. The length of the cutting part of the tool must be greater than the depth of the hole. Otherwise, the body of the part will block the helical grooves, through which chips are removed, and liquid is also supplied for cooling and lubrication.

First, the hole is drilled with a rigid short drill to a shallow depth. This operation is necessary to set the direction and centering of the main tool. After that, a hole of the required length is made. As you progress, you need to remove metal shavings from time to time. For this purpose, use coolant, hooks, magnets, or turn the part over.

During the construction of pipelines, laying sewers and other works, it periodically becomes necessary to make a hole in a pipe of a certain diameter and shape. On the one hand, this simple work, which can be performed by novice masters on their own, on the other hand, any process has its own nuances and difficulties, which it is desirable to know about in advance.

Preparation for work

To drill a hole in a pipe, you need:

prepare the necessary equipment;
learn the nuances of the process to avoid mistakes.

Necessary equipment

Cutting holes in pipes is done using:

conventional drill or special professional tool. A special machine is used by people whose profession is related to the installation of pipelines. For home purposes, a drill with a speed control function and a set of various drills is enough;

vice for fixing the pipe;
a file with which, if necessary, it will be possible to expand the hole;
a hammer. With the help of this tool, small diameter holes are punched;
a wooden block or a homemade template that fixes the drill in a given position.

When cutting holes, do not forget about basic safety precautions. When drilling pipes, it is recommended to wear protective gloves and goggles.

Nuances

Determine the type of material used to make the pipe. Each material has its own characteristics that must be taken into account.
Determine the wall thickness of the pipe. The larger this parameter, the more powerful the equipment will be required. When drilling a through hole, it is necessary to take into account and outside diameter pipes.

To give the drill additional stability, a wooden block or a special template is used:
- if a bar is used, then it is necessary to drill a hole of the required diameter in it and fix the finished structure at the location of the hole in the pipe. The width of the bar (about 50 mm) will fix the drill and will not allow it to deviate from the given direction;
- homemade template is also made from a wooden block. The main difference between the designs is that the template contains several prepared holes of different diameters and is equipped with a mounting vice, while the bar must be prepared for each hole separately.

when drilling metal and cast iron, the drill may overheat, so it is recommended to periodically moisten it with cold water;
only sharp drills, most suitable for a particular material, can be used.

Taking into account all the mentioned nuances will allow you to quickly and accurately make the necessary holes.

Small diameter holes

General drilling pattern

Drilling holes in a metal pipe, including in profile pipe from metal, produced according to the following scheme:

the pipe is securely clamped in a vice;

if it is required to cut several holes, then the pipe is pre-marked. For this, a tape measure and a marker are used;
a prepared bar or template is installed in place of the hole;
the drill is wetted in water to prevent it from overheating;
drilling is performed.

When working with metal pipes as additional lubrication and protection against overheating of the drill, it is recommended to use:

machine oil for steel pipes;
soap solution for copper products.

Features of work on cast iron pipes

Drilling holes in cast iron pipe requires:

compliance with all safety standards. Since small chips may form during the operation, in addition to protecting the eyes and hands, it is recommended to use a respirator or gauze bandage. In addition, in the room where the work is carried out, there must be high-quality ventilation;
drilling a hole in a sewer pipe made of cast iron is recommended at low speed drills. The power of the equipment can be gradually increased;
for drilling, drills with victorious tips are the best choice.

Features of work on plastic pipes

Cutting holes in plastic pipes, for example, in drain pipe is the easiest task. This does not require special equipment. All work can be done with a simple drill.

When drilling, there are some features:

it is necessary to cut holes at the minimum speed of the drill, since under the influence high temperature the pipe may be deformed;
if even and neat holes are required, then after drilling it is necessary to refine them with a small file or a sharp knife.

Drilling large holes

Now let's look at how to cut a hole for a pipe in a pipe or how to make holes of large diameters. For this you need:

fix the pipe and apply markings on it;
according to the scheme described above, drill a hole of small diameter;
put on a drill a special nozzle for drilling large holes;

insert the center drill into the prepared hole;
carefully, first at low speeds of the tool, make a hole of the desired diameter.

When working with nozzles, the drill must be kept in a strictly vertical position. Due to the slightest shift in the equipment, the hole will turn out irregular shape and at an angle.

If a hole with a size of 5 mm to 10-15 mm is required, then the use of special nozzles is not required. It is enough to first drill a small hole, and then use a larger diameter drill to bring the hole to the desired size.

Cutting square holes

Square holes are most often cut into square tube for connecting sections into a finished structure. There are several ways in which such holes can be made. The first one is as follows:

on the pipe section, the area and dimensions of the future hole are marked;
the first stage is cutting a round hole of small diameter according to the scheme presented above;
then a drill or nozzle of a larger diameter is selected, which is most suitable for the size of the circle inscribed in the square;
a round hole of large diameter is cut;
with the help of files different sizes a square (rectangular) section is made from a round hole.

The second way is to use a special nozzle instead of files. The preliminary stages completely coincide with points 1 - 4 of the above instructions. The prepared hole requires minimal rework.

The article discusses the method of drilling pipes without special equipment. How the drilling machine works is shown in the video.

So, drilling holes in metal, cast iron or plastic pipes is not a difficult task. If you have an ordinary drill with various drills and nozzles, you can make holes of different diameters and geometric shapes in a short time.

Sportsman 27-03-2007 10:53

I have been wanting to make a skeletal knife like "Flea" or "Bug" for a long time. Finger holes are 24 and 17 mm, respectively. How to make them? workpiece - a blade from a planer, steel 9hf (written). Maybe let go first? I have the opportunity to let go / temper in the forge ...

yunker 27-03-2007 11:06

let me insert my five cents, such a profile is cut out on a special laser machine from a sheet of iron, and if you can drill and drill at home, then honor and praise be to you. untranslated means craftsmen in Russia.

head 27-03-2007 11:06

According to the released, I would try, for example, "ballerina"

Sportsman 27-03-2007 11:31

I tried to drill - the blade from the planer on the machine is drilled normally. Moreover, the blade is Soviet, our tool factory. It is clear that it is cut with a laser or something else, but I don’t believe that it’s impossible to do it artisanally. Maybe, of course, slightly crooked holes will come out, but I'm not going to calibrate the sleeves. You can generally deliberately fill up, i.e. pull it into an oval, supposedly on purpose ... I’ll probably try it traditionally - drill it out with a drill for 14, then I’ll look for a cutter, I was somewhere, then a rasp ...

sergeant 27-03-2007 11:36

Sold special crowns for drilling metal. but you need a drilling machine for them. there, the cutting efforts are large, it is very difficult to hold the handles.

SiDiS 27-03-2007 11:54

Nothing prevents drilling holes along the contour dia. from 3mm and connect them with vulcanite on a dremel. Then smooth with an abrasive cutter
If you want to make perfect - take a cone with a small taper and grind from 2 sides. At the same time you will make chamfers

Val13 27-03-2007 12:18

On tempered metal, it is very convenient to increase the diameter of the hole with a set of Morse taper reamers. Center drills also come in a very "adult diameter. Deep drilling cannot be done with them, but a few millimeters is easy. Again, abrasive consumables for Drimel are sold almost in buckets everywhere. tiles), only with water and do not press down hard. There are many options. IMHO diamond is better, since it is not known in advance where this openwork structure will be unscrewed during hardening

Sportsman 27-03-2007 12:31

O! Cone bowl! A good idea! About the vacation - I meant just first to make holes in the workpiece, harden it and only then cut the contour, it’s not very hard on a grinder and a grinder ...

Volkov 27-03-2007 15:36

The hole can be etched electrochemically, and then leveled with the same cutter.

Sportsman 27-03-2007 16:34

quote: Originally posted by Volkov:
The hole can be etched electrochemically, and then leveled with the same cutter.

So the point is not that the hole is difficult to make (I’m saying that the workpiece is drilled quite well, you can drill holes and finish with a rasp), but that you want a perfectly even hole, that’s the trick ... tomorrow they promised to bring an 18mm drill I'll give it a try and then we'll see...

avb 27-03-2007 17:47

It's a pity to waste time on such crap.

Val13 27-03-2007 21:20

If with a drill, then it is worth clamping it into a bag with at least hard wood, otherwise such a diameter with any sharpening of the drill (at such a metal thickness) will make a hollow, and not an even hole

Sportsman 28-03-2007 16:46

It’s not a pity to waste time, so you can say about any knife and about any business in general ... I made the holes: I went through with drills: 6-10-12-14-17 then with a corundum cutter on the machine, as advised. IMHO it turned out well, I'll blacken it in oil, then I'll show you. the main problem is that the planer blade has zone hardening, it is hardened 35-40 mm from the cutting edge, no further. One, the largest hole fell on the border of the zones. The drill all the time tried to move from the hardened zone to the raw metal. In the end, somehow still drilled through.