Drilling holes in metal fer
Hole machining
Holes can be machined: drilling, countersinking, reaming, boring, broaching, grinding, honing, superfinishing, lapping, sizing and rolling.
Drilling is used to create holes in solid metal. Holes with a diameter of more than 30 mm in solid material are drilled with two drills, i.e. drilling and reaming.
Gun drills are used to drill deep holes. For large diameters, it is advisable to use annular.
Drilling and reaming allows you to get 11-12 grade and Rz = 30. 80 microns.
When making holes on 8. 10 grade of accuracy and Ra-1.2. 3.0 microns after drilling apply countersinking.
Cast or stamped holes are usually processed immediately with a rough countersink, which allows you to get 9-11 quality and Rz = 15. 40 microns.
With the simultaneous processing of several holes d 30 mm located on the same axis in serial and large-scale production, mandrels with mounted countersinks are used.
In large-scale and mass production, combined countersinks are widely used, which simultaneously process a hole, an end face and a chamfer, as well as combined tools: a drill. countersink.
If it is necessary to obtain hole accuracy up to 4. 5 quality and roughness Ra = 0.3 µm, deployment is used, and a rough deployment allows you to obtain; 8-9 accuracy grades and Ra = 1.2. 2.0, finishing deployment: 6-7 accuracy grades and Ra = 0.6. 1.2 and fine deployment 4-5 quality Ra = 0.3. 0.6 μm.
In large-scale and mass production, combined tools are often used: a drill. reamer or drill. countersink. scan. Drilling, countersinking and reaming of holes is usually performed on lathes, boring machines or turret lathes.
In single, small-scale and serial production, vertical drilling or radial drilling machines are used. over, for a quick change of cutting tools on these machines, quick-change chucks are used. In small-scale and serial. CNC machines. In large-scale production. aggregate, in mass. automatic machines and semiautomatic devices.
For finishing holes, thin or diamond boring is often used, which is carried out in the following modes:
cutting speed for cast iron 120.150 m / min, for bronze 300.400 m / min, for babbitt 400.1000 m / min, for aluminum alloys 500.1500 m / min.
The advantages of fine boring are:
no caricature of abrasive grains;
high accuracy is achieved: 5-6 quality;
simplicity of the cutting tool design.
Recently, more and more widely used is boring holes with wide cutters installed in special blocks.
These blocks are usually made floating.
Boring is used for processing holes d 80 mm.
Boring can be rough, fine and fine (diamond).
Rough boring allows to obtain 10-12 accuracy grades and Rz = 20. 80 µm, finishing. 8.9 precision grades and Ra = 1.2. 5.0 μm, fine. 5.7 grades Ra = 0.2. 1.2 μm.
Hole boring can be carried out on various turning, drilling, vertical and horizontal boring machines with CNC and modular machines, automatic machines and semi-automatic machines.
In mass, large-scale and serial production, pulling of holes of cylindrical, spline and other shapes is widely used.
Cylindrical holes are pulled after drilling or countersinking, it replaces hole drilling and allows you to get 5-7 accuracy grades and Ra = 0.3. 1.5 μm.
Broaching is performed on horizontal and vertical broaching machines.
Holes are grinded on internal grinding machines. The diameter of the grinding wheel is usually taken as dcr
Transverse (radial) feed. 0.003. 0.15 mm for one double stroke. Longitudinal feed: 0.2. 0.35. for fine grinding and 0.6. 0.85 for rough grinding (5. grinding wheel width). In large-scale and mass production, semi-automatic internal grinding machines are used.
In addition to conventional grinding, large-diameter holes can be ground on machines with planetary spindle movement, as well as on machines for centerless grinding (Fig. 7.6). Grinding allows you to get 5-8 qualities and Ra = 0.2. 2.5.
Honing allows you to get 4-6 accuracy grades and Ra-0.04. 0.6 μm.
Holes are honed on honing machines with a special rotating head (hon) with sliding abrasive or diamond stones, which, in addition, have a reciprocating motion. The movement of the bars in the radial direction is carried out by a mechanical, hydraulic or pneumatic device.
Recommended Honing Modes: Allowance. 0.05. 0.1mm, honing head rotation speed. 60 75 m / min for steel; the speed of the cart in the rati o-post on
body movement of the head. 12.15 m / min.
Nowadays, honing with diamond stones for roughing is successfully used.
Recently, flat-top honing has been successfully used to increase the bearing capacity of the surface (increase / p) with oil s from previous processing (Fig. 7.7). It allows you to get: /] O60, Sm = 0.05. 0.5 at Ra = 0.4. 1.0 μm.
Lapping (lapping) of holes is carried out on turning, drilling, internal grinding and special lapping machines.
Lapping is done with cast iron or copper lapping, pressed to the surface of the part by springs. Lapping allows you to get 4-5 quality of accuracy, Ra = 0.04. 0.2 μm, t1050, Sm = 0.05. 0.2, does not correct the shape error. Recently, more and more widespread use has been made of synthetic diamond lapping bars.
Drilling and reaming holes, tapping
Drilling holes
Holes in various products are drilled with drills installed in drilling machines, drills, rotors. In plumbing, twist drills are most often used, since they are easy to drill and give a clean hole of more accurate dimensions.
Twist drills are available in standard diameters with a sharpening angle (tip angle) of mostly 116 degrees. A drill with this sharpening angle is suitable for drilling in both hard and soft materials.
The drills are sharpened on special machines or manually on an emery wheel. The correctness of sharpening is checked using a special template. For a well sharpened drill, the cutting edges should be exactly the same length and at the same angle to the axis of the drill. The middle of the bridge should be on the axis of the drill and form an angle of 55 ° with the cutting edge.
The back angle of sharpening with a template is not checked, but it should be equal to 6 ° at the outer surface of the drill and increase towards its axis up to 20 °. If these sharpening rules are not followed, the drill will hit, go to the side, it is bad to take chips and quickly heat up, and the resulting hole will be incorrect.
Drills (left spiral, right pen)
In the absence of twist drills of the required diameter or length, feather drills can be used. They are easy to make yourself from a bar of carbon tool steel. For this, a bar of the required dimensions is heated and flattened at one end in the form of a spatula.
This end is hardened and then sharpened on an emery wheel so that cutting edges are formed at the tip of the drill at the desired sharpening angle. For drilling steel, the sharpening angle is taken equal to 120 °. for brass. 90 p. for aluminum 80 o.
To drill a hole, insert the selected drill until the drill chuck fails and clamp it slightly. Then check that the drill does not hit when rotating, and clamp it in the chuck as much as possible.
Before starting drilling, it is necessary to deepen each center of the outlined holes by re-punching, and then fix the product in a vice on a workbench so that it does not bend or move during the drilling process.
The drill, first you need to set perpendicular to the surface of the product, then, slowly and carefully drilling a small depression, check whether the drill coincides with the center of the punching.
If it has moved away from the center, then it is necessary to make a deeper punching or cut two or three radial grooves from the center of the recess with a cross-cutter in the direction where the drill should be fed. In this case, the drill will take large chips where the grooves are applied and move to the desired direction.
If this time it turns out to be eccentric, then it is necessary to make a new punching, drill a hole with a thin drill, and then with a drill of the required diameter. The pressure on the drill should be such that it delivers uniform chips. When the drill comes out of the metal, it is necessary to reduce the pressure, since at this moment the drill picks up large chips and can break.
When drilling deep holes, remove the drill more often and free it from jammed chips. In addition, to reduce the heating of the drill, it is necessary to apply drops of lubricant into the hole with a brush. This will result in a cleaner and more accurate hole.
When drilling steel, ductile iron, red copper and brass, use mineral oil or soapy water, and when drilling aluminum, soapy water and kerosene. Gray cast iron and bronze are dry drilled.
A large hole is drilled in two passes. First, the hole is drilled with a small-diameter drill, and then with a drill of the required diameter. This method is due to the fact that drills with a smaller diameter are easier to install at the drilling point. In addition, the hole is more correct and more accurate.
Particular care should be taken when using an electric drill with thin and long drills. In such cases, the worker needs to take a comfortable and stable position. The drill must be directed so that the axis of the drill coincides with the axis of the future hole.
It is advisable to finish drilling once, without removing the drill from the hole and not tilting the drill to the side, since the slightest tilt of the drill will break the drill. In this case, the feed is needed very small, and if the drill is in a vertical position, then the drill feed is carried out by the weight of the drill’s own weight.
When drilling large and shaped holes in sheet metal, a number of small holes are pre-drilled next to each other so that they almost reach the marking mowing line. The gaps between these holes are cut with a cross cutter, and the irregularities are cut with a file. Holes in cylindrical parts are drilled on a stand with a cut out recess.
Reaming holes
Reaming is the process of machining holes by reaming. Reaming of holes is performed when assembling parts, when a slightly larger hole is required or greater accuracy and purity of its finish, for example, for calibrating the bore of bushings.
In plumbing, manual cylindrical and conical reamers are used. Manual reamers have a large intake (working) part, and their tail has a square for putting on the wrench.
Tapered reamers are used for stripping and straightening tapered holes. It is also convenient to use conical reamers to expand the holes in the sheet material, in the chassis of the blocks. Reamers are made in a set, three pieces per set (rough, transitional and finishing) or two each (transitional and finishing).
Expansion of holes on a cone for countersunk heads of screws, screws and rivets is made by conical countersink.
During manual work, the reamer should be rotated with a knob, for which leave it in the square hole of the knob.
Before using the reamer, it is necessary to check all its cutters by touch and, if any burrs are found, remove them. To obtain a hole of exact dimensions, the hole is pre-drilled with a drill, the diameter of which is 0.2 less than the required hole diameter. 0.4 mm, which provides a stock of material for deployment.
The product is clamped in a vice so that the hole is in a vertical position. Then the transitional reamer is left with the lower part in the hole and rotated with a knob towards the direction of the tip of the teeth. To obtain a hole of more accurate dimensions, a finishing one is used after a transitional sweep. It is necessary to rotate the reamer with pressure, run through the hole. You can not rotate the sweep in the opposite direction.
Threading
In the repair business, threads are cut mainly by hand. Taps are used for cutting internal threads, and dies and screw boards are used for cutting external threads.
Locksmith kit:
Internal threading
According to the method of application, taps are divided into manual (locksmith) and machine.
Hand taps are produced in sets. The set includes three taps: rough (first), middle (second) and finishing (third). All three taps are made so that the thickness of the chips cut by each tap is more or less the same. The third tap is used last for finishing and calibrating threads.
It is very important to select the correct drill diameter for drilling holes for threads.
For threading in soft metals such as copper or aluminum, the diameter of the hole must be taken slightly larger, since when cutting, such metals are squeezed out, causing the tap to jam and gall the thread.
The thread is cut as follows: the product is clamped in a vice, and the end of the first tap is inserted into the hole as accurately as possible and pressed on it with a knob.
At the beginning of work, the crank is taken with the right hand, grasping the tap with the thumb, middle and forefinger, and with slight pressure slowly rotate the tap clockwise, keeping its vertical position. As soon as the tap begins to pick up the chips, they switch to rotation with both hands. Having made one turn to the right, make half a turn to the left, etc. Having passed the hole with the first tap, replace it with the second, and then with the third.
With a cutting length of up to 5 mm, only the first and third taps are dispensed with, and for cutting less accurate threads, it is enough to use the first two taps. When cutting deep holes, unscrew the tap more often and clean it with a brush from shavings, and lubricate the cutting area with two or three drops of oil. Holes in bronze and gray cast iron are dry cut.
External threading
Dies and screw boards are used for cutting external threads. Dies are round (split and continuous). They are also called lerks. For work, the die is inserted into a special die with clamping screws.
Threading with round dies and screw boards is performed in the same way as with taps. When cutting with dies, it is important that the diameter of the rod is slightly less than the outer diameter of the cutting of the dies.
The cutting bolt is fixed in a vice and slightly rounded from above with a file for better grip with the die. Having lubricated the bolt with oil, put on a die on top and, pressing strongly on it, at the same time turn the klupp to the right. As soon as the die takes the chips, the die is rotated in the same way as when working with a tap, that is, after each full turn, make half a turn back. The thread is cut in one to two passes.
Drilling holes: in wooden structures with an electric drill with a diameter of up to 10 mm and a depth of up to 20 cm
FEDERAL SINGLE PRICE FERr 69-02-04
| Name | unit of measurement |
| Drilling holes: in wooden structures with an electric drill with a diameter of up to 10 mm and a depth of up to 20 cm | 100 holes |
| Scope of work | |
| 01. Marking of drilling points. 02. Drilling holes. | |
PRICE VALUES
The price does not include overhead costs and estimated profit, respectively, the direct costs of work for the period of 2000 (of the Moscow region) are indicated, which are calculated based on the standards of 2009. For further calculations, this cost must be multiplied by the index of the transition to current prices.
You can go to the pricing page, which is calculated based on the standards of the 2014 edition with additions 1
| Total (RUB) | Workers’ wages | Operation of machines | Remuneration for machinists | Cost of materials | Labor costs (man-h) |
| 108 | 89.57 | 18.43 | 0 | 0 | 10.5 |
UNACCOUNTED RESOURCES
| Cipher | Name | Unit Rev. | Consumption | Price Unit. | Total |
| 509-9900 | Construction garbage | t | 0.002 | 0.00 | 0.00 |
TOTAL PRICE: 108,00 RUB.
See the cost of this standard in current open page
Look at the resource part of the price in the standard HESNr 69-02-04
When used in an estimate, the quote requires indexing to be translated into current prices.
The price is compiled according to the standards of GESN-2001 edition of 2009 in of 2000.
Drilling holes: in brick walls with an electric hammer drill with a diameter of up to 20 mm, wall thickness 0.5 bricks
FEDERAL SINGLE PRICE FERr 69-02-01
| Name | unit of measurement |
| Drilling holes: in brick walls with an electric hammer drill with a diameter of up to 20 mm, wall thickness 0.5 bricks | 100 holes |
| Scope of work | |
| 01. Marking of drilling points. 02. Drilling holes. | |
How to use a hole saw to cut metal with a cordless drill
PRICE VALUES
The price includes only direct costs of work for the period of 2000 (for Moscow and the Moscow region), which are calculated according to the standards of 2009. To draw up an estimate, the cost of the work must be applied to the conversion index into the of the current year.
You can go to the pricing page, which is calculated based on the standards of the 2014 edition with additions 1
| Total (RUB) | Workers’ wages | Operation of machines | Remuneration for machinists | Cost of materials | Labor costs (man-h) |
| 57.11 | 46.83 | 10.28 | 0 | 0 | 5.49 |
UNACCOUNTED RESOURCES
| Cipher | Name | Unit Rev. | Consumption | Price Unit. | Total |
| 509-9900 | Construction garbage | t | 0.006 | 0.00 | 0.00 |
TOTAL PRICE: 57.11 RUB.
See the cost of this standard in current open page
Look at the resource part of the price in the standard HESNr 69-02-01
When used in an estimate, the quote requires indexing to be translated into current prices.
The price is compiled according to the standards of GESN-2001 edition of 2009 in of 2000.
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 table top from the drill going beyond the workpiece, which can damage the drill itself, as well as provide the workpiece with a “burr”. a garter. To avoid this, use the following methods:
- use a workbench with a hole;
- put a gasket made of wood or “sandwich”. wood-metal-wood under the part;
- put a metal bar with a hole for the free passage of the drill under the part;
- reduce the feed rate at the last stage.
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 nib drills because the twist drill will damage the edges of the workpiece.
Drilling by marking, template and jig
You can drill holes according to the made markings or without it. using a template or a jig.
Marking is done with a center punch. With a hammer blow, a place is marked for the tip of the drill. With a felt-tip pen, you can also mark the place, but the 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 inspection, and final drilling. If the drill has “gone” from the intended center, notches (grooves) are made with a narrow chisel, guiding the point to the specified place.
To determine the center of a cylindrical blank, a square piece of sheet metal is used, bent at 90 ° so that the height of one shoulder is approximately one radius. Applying a corner on 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.
The template is needed when performing a series of similar parts with several holes. It is convenient to use them for a pack of thin-sheet blanks connected by a clamp. In this way, several drilled workpieces can be obtained 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 it is very important to keep the distance between the holes and the strict perpendicularity of the channel. 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.
Types of holes in metal and how to drill them
- deaf;
- end-to-end;
- half (incomplete);
- deep;
- large diameter;
- for internal thread.
Thread holes require the determination of diameters with tolerances established in GOST 16093-2004. For common hardware, the calculation is shown in table 5.
Table 5. Ratio of metric and inch threads, as well as selection of hole size for pre-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 | ||
| min. | Max. | min. | Max. | ||||||
| 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 | one | 30.5 |
| M3.5 | 0.6 | 2.8 | 2.9 | 9/16 | 2.117 | 11.75 | 12.0 | – | – |
| М4 | 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 |
| М8 | 1.25 | 6.5 | 6,7 | one | 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 | – | – |
| М16 | 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 | – | – |
Deep holes, coolant
Sometimes a deep hole is required. In theory, this is a hole that is five times its diameter. In practice, deep drilling is called drilling, requiring periodic forced removal of chips and the use of coolants (cutting fluids).
In drilling, coolant is 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, the coolant can be omitted. Cast iron can be drilled relatively easily and without lubrication (except for high-strength).
In production, industrial oils, synthetic emulsions, emulsols and some hydrocarbons are used as coolant. In home workshops, you can use:
- technical vaseline, castor oil. for mild steels;
- laundry soap. for aluminum alloys such as D16T;
- a mixture of kerosene with castor oil. for duralumin;
- soapy water. for aluminum;
- turpentine diluted with alcohol. for silumin.
The universal refrigerated liquid can be prepared independently. To do this, you need to dissolve 200 g of soap in a bucket of water, add 5 tablespoons of engine oil, you can waste it, and boil the solution until a soapy homogeneous emulsion is obtained. Some craftsmen use lard to reduce friction.
| Processed material | Coolant lubricant |
| Steel: | |
| carbonaceous | Emulsion. Sulfurized oil |
| structural | Sulfurized kerosene oil |
| instrumental | Mixed oils |
| alloyed | Mixed oils |
| Malleable cast iron | 3-5% emulsion |
| Iron casting | No refrigeration. 3-5% emulsion. Kerosene |
| Bronze | No refrigeration. Mixed oils |
| Zinc | Emulsion |
| Brass | No refrigeration. 3-5% emulsion |
| Copper | Emulsion. Mixed oils |
| Nickel | Emulsion |
| Aluminum and its alloys | No refrigeration. Emulsion. Mixed oils. Kerosene |
| Stainless, heat-resistant alloys | A mixture of 50% sulfurized oil, 30% kerosene, 20% oleic acid (or 80% sulfofresol and 20% oleic acid) |
| Fiber, vinyl plastic, plexiglass and so on | 3-5% emulsion |
| Textolite, getinax | Compressed air blowing |
Deep holes can be made with solid and circular drilling, and in the latter case, the central rod formed by the rotation of the crown is not broken out entirely, but in parts, weakening it with additional small-diameter holes.
Solid drilling is performed in a well-fixed workpiece with a twist drill, into the channels of which coolant is supplied. Periodically, without stopping the rotation of the drill, you need to remove it and clean the cavity from chips. Work with a twist drill is performed in stages: first, take a short one and drill a hole, which is then buried with a drill of the appropriate size. If the hole depth is significant, it is advisable to use guide bushings.
If you regularly drill deep holes, you can recommend purchasing a special machine with automatic coolant supply to the drill and accurate centering.
Drilling on both sides is not recommended. at home it is almost impossible to perform the operation efficiently.
Complex holes
Holes located on the edge of the workpiece (half) can be made by connecting two workpieces or the workpiece and the gasket with the edges and clamping them with a vice and drilling a full hole. The gasket must be made of the same material as the workpiece to be machined, otherwise the drill will “go” towards the least resistance.
A through hole in the corner (shaped metal rolling) 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 the platform perpendicular to the hole (milling, countersinking) and the actual drilling. Drilling holes in angled surfaces also begins with site preparation, after which a wooden spacer is inserted between the planes, forming a triangle, and a hole is drilled through the corner.
Hollow parts are drilled by filling the cavity with wood cork.
Shoulder 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 reamed 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 the maximum diameter is drilled to a given depth, then the drills are changed with a sequential decrease in the diameter and deepening of the hole. This method makes it easier to control the depth of each step.
Reaming the hole. 2. Reducing the diameter
Large holes, circular drilling
Making 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 tapered, or better step-taper drills. For holes with a larger diameter (up to 100 mm), you will need hollow bimetallic or carbide-tipped bits with a center drill. over, the craftsmen traditionally recommend Bosch in this case, especially on hard metal, for example, steel.
This hole drilling is less energy intensive, but can be more costly. In addition to drills, the power of the drill and the ability to work at the lowest speeds are important. over, the thicker the metal, the more you will 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 fixed to an “angle grinder”, but the edges in the latter case leave much to be desired.
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 a chuck with an adjustable stop;
- using a ruler fixed on the machine;
- a combination of ways.
Some machines are equipped with an automatic feed to a predetermined depth, after which the mechanism stops. During the drilling process, it may be necessary to stop work several times to remove the chips.
Diamond drilling in concrete
Diamond drilling of holes is used for hard materials. Usually, special nozzles are used for this, which have a spray or solder on the end. In the first case, we are talking about piece diamonds, while in the second. about a victorious alloy. These solutions are quite popular, but diamond tools have many advantages over victorious ones.
Diamond drilling of holes involves the use of core bits and drills. In the latter case, there is diamond chips at the end of the working part, which is capable of crumbling concrete without the impact of an impact load. This advantage can be called the first factor that makes consumers choose this method. The hole is made without hitting, so the work is not accompanied by noise, and the result is more accurate.
Concrete drilling tools
Household rotary hammers and industrial tools are used as equipment for making holes in concrete. The hammer drill allows you to get holes of small depth and diameter. As for professional drilling equipment, it can be used to make holes in concrete to an impressive depth. If you need to get a large hole, then devices are used, the working part of which is a diamond drill. Such equipment can additionally use a dust and crumbs outlet through special channels. This allows for neatness.
Drilling holes in concrete sometimes requires additional cooling of the drill. In this case, water is supplied to the work area. Additionally, it acts as a purifier. Crumbs and dust are flushed out of the hole, and the water is drawn out by a special vacuum device that works on the principle of a vacuum cleaner.
Drilling holes in metal
Drilling the hole is completed by recessing the drill. To do this, the drill turns in the opposite direction, if the design requires such a function. To work with metal, a drill stand is often used, on which it will be possible to fix the tool. In this case, at the beginning of work, the handle will only need to be pressed lightly. When the shavings go, the pressure will need to be increased.
Drilling holes in metal involves maintaining the relationship between the thickness of the drill and the number of revolutions of the tool. The larger the drill diameter, the lower the RPM should be. For example, if the drill is 4 mm in diameter, then the revolutions should be equal to the limit from 2400 to 2800 per minute. If the diameter increases to 8 mm, then the number of revolutions should be reduced to 1300 per minute.
Using a hammer drill to drill concrete
Drilling holes in concrete can be done with a hammer drill. It allows you to solve simpler problems. The selected nozzle will determine the parameters of the hole. A conventional rock drill is capable of working in one of three modes, among them:
- rotation without impact;
- rotation with a blow;
- non-spinning impact.
The first of the mentioned modes is relevant for making holes in metal. The second mode is used to work with brick and concrete walls; in this case, winder drills should be used. And to make holes with a perforator, you should prepare a drill with a victorious soldering. Combining operation in rotation mode with impact, such a drill will allow you to make holes for dowels, as well as for laying water pipes and wires.
When using this tool, be aware that the working part may overheat. The equipment should be installed at medium speed, and the drill should be periodically wetted with water. If you need to make a deep hole, then the technology is used in several passes. If it is necessary to form a hole with a large diameter, a crown should be used as a tip.
Drilling a hole in metal and concrete: methods, tools and recommendations
When carrying out repairs and construction, it is often necessary to drill holes in different materials, among them concrete and metal should be distinguished. This requires skills and special tools. Modern craftsmen have no problems with carrying out such work.
On the market, you can find devices that can facilitate the described task. Tools allow you to punch holes in hard material, ensuring accuracy, speed and accuracy.
Metal Drilling Tips
The hole can also be drilled in metal. To begin with, it is important to choose a drill, while saving is not worth it. A high-quality consumable usually costs 300 rubles. Next, the surface is prepared. Before starting work, the central part of the hole should be punched to prevent the drill from slipping. The work is carried out with a center punch, which looks like a metal pointed rod. The master will have to hit it with a hammer, while the point forms a notch.
The hole is drilled according to a certain algorithm. If you have to work with metal, the thickness of which exceeds 5 mm, then it is advisable to use several drills. Work needs to be started with a drill of a smaller diameter, after which holes are drilled with a drill of a larger diameter. The drill is switched on at low speed, in the process of work it is necessary to increase the speed. To facilitate the process, a board is placed under the metal. This will keep the hole neat and straight.
Why you should prefer diamond drilling
After the hole has been made, an almost perfectly smooth base is obtained at the exit, which does not require additional processing. Drilling holes in concrete in this way allows you to deepen several meters. The same applies to the diameter. Diamond drills allow you to get an impressive diameter quickly and accurately. This technique helps to form styling channels:
- sewerage systems;
- water supply;
- hoods.