How to drill properly How to properly drill metal and concrete. Drilling tips for various materials.
Drilling concrete
Drill bits with victorious tips Holes in concrete can be needed for a wide variety of purposes. The need for them may arise during routine repairs. For example, holes in a concrete wall are required when installing a toilet and other plumbing, for installing shelves and sliding doors. There are tons of examples when you need to use a drill to work with this material. Concrete has its own special properties, therefore, work with it is also carried out according to certain rules.
How to drill concrete? For this purpose, you need to purchase drills with victorious tips.
It must be remembered that a drill is used in working with concrete only for drilling small holes (up to 12-13 mm). If you need to make a larger hole, it is better to use a hammer drill.
Drill breakage and jamming are the most common problems when drilling in concrete. Drills can also become clogged, so they must be cleaned and sharpened regularly.
Drilling is done as follows:
- First, the point is marked at which the hole will be made.
- Then you need to make a small depression at this point with a conventional drill.
- Is the deepening ready? So it’s time to change the conventional drill to an asymmetric one. It will allow you to work more efficiently.
- If the hole is made for a dowel, then it must exceed its size. Because concrete dust will significantly reduce the headroom.
- It is better if the drill used in the work has a built-in level. Anyone who has already drilled concrete knows how difficult it is to keep the tool in an even position at all times. Especially if the work is long.
- During operation, the drills can be regularly moistened with plain water. This makes the process easier.
Drilling metal
To properly drill metal, you need to know the properties of this material. It is very hard, difficult to mechanical stress and requires drills of a certain strength. If the drills are bad, the job will not work. It is not recommended to save on tools, because a poor, low-quality tool can destroy the material.
Drilling thin metal sheets is a real flour for most craftsmen. Steel tends to break free, which can lead to serious injury. To prevent this from happening, the steel sheets must first be fixed. To do this, you can make a special device that will clamp the steel.
When cutting a blind thread, various debris often gets into the hole. To eliminate this phenomenon, you need to pour a little paraffin or wax inside.
Drilling tiles
Drill selection
Tile is a very fragile material. Wrong move and it might just crack. To properly drill a tile, you need to follow simple rules. First of all, you need to select special drills that are soldered from carbide. This will reduce the stress on the work surface and facilitate the drilling process.
The point where it is necessary to make a hole must be marked in advance. This is done with a tap or marker. This point will ensure that the drill does not slip. The mark is made on the outside of the tile.
Sometimes it is necessary to drill a tile that is already glued to the surface. In this case, glass drills can be used. There are no special secrets when drilling tiles. The main thing is not to exert too much effort, otherwise the tile will crack. The better the drill, the easier the work process is.
How to drill concrete walls
In everyday life, you have to drill walls most often, because without this it is impossible to hang a shelf, cabinet, you cannot install a cornice. Of course, it is better to use a hammer drill or an impact drill for this purpose. These tools are powerful enough to tackle hard materials such as concrete or brick. However, if the wall thickness does not exceed 10-12 cm, then you can do with a conventional drill. But you should not risk it if you only have a low-power tool at your disposal, when it comes into contact with concrete, it can simply break. If the drill is selected correctly, then the following tips will be useful:
- Before starting work, you should make sure that there are no pipes or other communication systems in the place of drilling.
- The drills that are taken for such work must be made of hard metals or alloys. The best option would be diamond drills.
- If, during the drilling process, you come across too dense areas of concrete, they must be punched with a small hammer and a pin (punch).
While it is generally possible to drill a concrete wall with a drill, it is still worth doing it with care. Otherwise, breakdowns can be quite serious. It is better to use specialized tools for this.
How to work with tiles with a drill
Often, people who do not have rich experience in the field of repair are afraid to drill such a fragile material as tiles. However, this can become an urgent need, because you need to attach a variety of cabinets and shelves to something in the kitchen, bathroom or toilet. Alas, in many respects the state of the tile after drilling is determined not by the master who takes the drill, but by the one who laid the tile. A competent tiler lays the tiles so that voids do not form between the tile and the wall. In this case, careful drilling will in no way harm the tile. If there are air pockets between the wall and the tile, then most likely the tile will crack.
In order to properly drill the tile, you need to take a drill, masking tape, perforator (or a powerful drill with drill bits for concrete). Next, you will need to do the following:
- The drilling site is marked with a piece of masking tape and a marker. The adhesive tape is here so that the nail does not slide over the surface of the tile.
- Drilling is performed strictly perpendicular to the material. The number of revolutions should increase gradually: from the minimum possible to 150-200 revolutions per minute. This avoids damage to both the material and the tool.
- It is important to ensure that the drill does not overheat. If smoke begins to go, then the drill needs to be urgently cooled.
When the holes are made, you can insert dowels into them. This is done with a hammer.
Drilling details for various materials
Drill selection
When purchasing drills, you need to keep in mind that conventional drills made of high-speed tool steel (for example, P6M5) are designed for drilling metals that do not have high hardness. To drill through hard metal, you will need carbide drills. These drills can be all-carbide or have only a carbide tip.
Sometimes, before starting drilling, it is not known what hardness the metal is to be drilled. Therefore, upon seeing at the first moment of drilling that the drill does not penetrate into the metal, you must immediately stop drilling, otherwise the drill will be irrevocably damaged, overheating and losing its hardness. This will be evidenced by the appearance of a dark blue color on it. Before drilling into metal, the hardness of which is not known, you can file it over it. If the latter does not leave traces on the metal, then the material has increased hardness.
Drilling metal
How to drill metal
When drilling metal, the sharpness of the drill is very important, while the drill becomes blunt very quickly. The bluntness rate of the drill depends in particular on the revolutions, feed force, cooling and other factors, however, no matter how hard you try, if a non-aluminum alloy is drilled, the operating time of the drill to unsatisfactory performance is measured in minutes.
Before drilling, mark the hole by punching it in. To do this, you need to install the tip of the center punch (or dowel) in the intended center of the hole and hit it with a hammer. Punching is necessary to prevent slipping of the drill at the first moment of drilling. If the core track is not large enough to hold a large diameter drill, the hole should be widened with a small drill first.
To create better drilling conditions, it is advisable to dip the tip of the drill into machine oil or drop it into the punching site. Oil in the drilling area helps to cool the drill and makes cutting metal easier. The drill, which is drilled using oil, dulls less, requires less sharpening and lasts longer. A special emulsion, soapy water, and kerosene are also used as a coolant. According to some artisans, lard is a good lubricant and cooling agent. Before drilling, the rotating drill is immersed in a piece of bacon, which melts during drilling and has a lubricating and cooling effect. But still the simplest and most convenient remedy is soapy water. It does not stain, and there is soap in every home. It is enough to drop it once at the beginning of drilling and in the process. You can periodically dip the drill in soapy water.
When drilling through with a high feed, a burr (burr) is formed at the exit of the hole, to which the drill clings with its lateral cutters. As a result, a sharp blockage of the drill and its fracture or chipping of the cutter can occur, and even at this moment the drill becomes especially blunt. Such stops have a negative effect on the condition of the drill. To avoid burr formation, you need to finish drilling holes in the metal at a low feed. It is also advisable to place a wooden block under the part to be drilled, which prevents the formation of a burr. The bar and the workpiece must be tightly pressed against each other. For greater effect, you can put not a wooden block, but a plate of the same or less hard metal, which should be tightly pressed against the drill exit.
Most often, you have to drill steel, but often you have to drill other metals that have their own drilling characteristics. Aluminum, for example, envelops the drill, making it difficult to penetrate and widen the resulting hole. If you want to drill a precise hole in aluminum (for example, for a thread), it is imperative to use a coolant and often remove the drill from the hole to clean it. Conventional gray cast iron drills relatively easily and requires no cooling or lubricating fluid. But drilling in cast iron can be a surprise. There are ductile cast irons that need to be drilled with a carbide drill. White cast iron, the main structural constituent of which is cementite, is very hard and requires a high strength drill.
Large holes should be drilled in stages. First you need to drill the part with a thin drill, then drill the hole to a larger diameter. For example, a 12 mm hole is best drilled in two or three steps. Sequentially with drills 5, 10 and 12 mm.
Dull drills must be sharpened in a timely manner. It is best to do this with a sharpener, but you can do without it. In this case, you need to pay attention to the symmetry of the drill tip. If the sharpened edges do not converge exactly in the center, the hole drilled with such a drill will have a larger diameter, since one cutting edge will be longer than the other. The standard nose angle (angle between cutting edges) is 118. For drilling in aluminum, the optimum angle is 130-140, soft bronze and red copper 125-130. However, all of these metals can be drilled with a standard angle drill. Read more about sharpening a drill here.
When drilling, it is necessary to maintain the verticality of the drill relative to the metal surface (if you do not need to drill an inclined hole). When making holes in thin sheets, this requirement is not as relevant as for thick-walled or hollow parts. Drilling pipes, for example, often results in the inlet and outlet holes being offset from each other. The larger, the larger the pipe diameter. It is quite difficult to maintain the perpendicularity of the drill by eye, so you can use homemade or purchased jigs for drilling or guides that ensure the perpendicularity of the drill.
Jigs are also needed to drill two or more holes in mating parts. The best way to ensure the holes match. This is drilling them together. When drilling holes for rivets, drilling complete is a must. Once you have drilled the first hole, you can use it to bolt the parts together so that you can drill the rest of the holes without the fear that the parts will move relative to each other. If it is impossible or inconvenient to drill the mating parts in the assembly, then the jig or guide must be used. You should be aware that no matter how accurately the mating holes are marked and pored, they will not coincide absolutely exactly, since when drilling even a punched hole, the drill will go a little to the side.
Chip formation during drilling
Drilling metal produces sawdust or small chips (when drilling soft metals such as brass) or long chips (when drilling hard metals such as iron or steel). Special drills are available for each of these types of metal. The cutting edge of the soft metal drill is flat (A). This is done so that such drills do not bite in the metal; they can also be used for other soft materials such as plastic or nylon. Hard metal drill bit sharply sharpened (B).
Drilling large holes
If you want to drill a large hole in the metal, you must first drill the hole with a smaller drill. This will allow the larger drill to cut metal more efficiently and reduce the chance of warping. If necessary, pre-drilling can be performed in several passes, gradually increasing the diameter of the drills used.
When pre-drilling, the diameter of the small drill (B) must be at least the diameter of the web of the larger drill (A). The drill bridge is the shortest distance between two cutting edges.
When pre-drilling, the diameter of the small drill (B) must be at least the diameter of the web of the larger drill (A). The drill bridge is the shortest distance between two cutting edges.
Drilling speed
A common mistake when drilling metal is too high a rotational speed. The harder the metal to be drilled in, the lower the drilling speed should be. For example, when drilling an 8 mm hole in brass, the rotational speed of the drill should be set to 2500 rpm. In the case of stainless steel, which is a much stronger metal, the correct speed is 800 rpm. A good indicator that the speed is set correctly is the formation of nice long chips.