How to choose a drill: a complete guide for professionals and beginners
Choosing the right drill bit can make a big difference in the efficiency and quality of your work. But with a variety of types and models, making a decision can be a daunting task. Let's take a closer look at the main aspects that will help you make an informed choice.
Between lines and spirals: recognizing drills by their appearance
First you need to learn to distinguish between drills for metal and wood. The main difference is in the configuration of the working part. Metal drill bits have a point angle of approximately 118 degrees and chip removal channels, allowing you to drill even into hard metals. Wood drill bits have a more obtuse angle of about 135 degrees and wide spirals for quick removal of chips.
Pobedite drills occupy a special niche. These are drill bits with tungsten carbide inserts that are capable of drilling into very hard materials, including stone and concrete. They are easily distinguished by the gray or yellowish color of the working part and the absence of long spirals.
For each material - its own type of drill
Working with different materials requires specific drills. To drill holes for an M6 tap or M8 bolt, you need to use a 0.1 mm smaller drill so that the thread is well formed. If you need to drill into chipboard, it's best to use a drill bit with a sharp angle and fine flutes to minimize surface irritation.
When working with a variety of materials, be it metal, wood, plastic or ceramics, it is necessary to carefully select a drill to ensure not only a clean and accurate hole, but also to extend the life of the tool and work safety.
Drilling metals: subtleties of the process.
When drilling metal surfaces, drills with high hardness values are used. To create threads for an M6 tap (hole diameter approximately 5.0 mm) or for an M8 bolt (hole diameter approximately 6.8 mm), drills 0.1 mm smaller than the nominal diameter are used. This takes into account possible expansion of the hole during the drilling process and ensures a perfect thread fit.
Drilling wood: features of choice
The ideal drills for wood are those with a sharp centering tip, which ensures precise starting of drilling, and wide flutes for quick removal of chips. When working with laminated chipboard or other laminated materials, it is important to minimize delamination of the coating. Drills with thin, sharp flutes and minimal drilling pressure are suitable for this so as not to damage the laminate.
Drilling plastics: avoiding melting
Plastics require the use of drills with cutting angles adapted to the softness of the material. It is necessary to drill at low speeds to prevent overheating and melting of the material. Drills for plastic usually have a more obtuse cutting angle, which reduces the risk of chips and cracks.
Drilling ceramics and tiles: no chips or cracks
Ceramic materials require the use of diamond or carbide drills. Operation is carried out at minimum speed without shock and using water cooling to prevent overheating. It is important to start drilling at an angle to create a small groove that will guide the drill and prevent it from sliding across the surface.
Drilling in concrete and stone: strength and precision
Pobedite or diamond drill bits are suitable for these materials. The impact mode of the drill is used, which helps to destroy the solid structure of the material. Drilling must be carried out with cooling and always with periodic pauses to avoid overheating.
Features of dowel installation
For reliable fastening in walls or ceilings, dowels are used, which require an exact match to the diameter of the hole. If the recommended drill size for the dowel is 10 mm, then the hole should be exactly the same. This guarantees a tight and secure connection.
Tips and tricks for drilling
To make drilling effective and safe, you must follow some recommendations. Drills need to be sharpened and lubricated regularly. When working on metal, use special coolant or oil. This will reduce friction and prevent the drill from overheating.
It is not recommended to use metal drills for wood and vice versa. Metal drills can become clogged with wood shavings, and wooden ones can quickly become dull from the metal.
Drilling problems
Problems during drilling can arise not only because the drill does not match the material, but also for a number of other reasons that are important to know about in order to avoid breakdowns and accidents.
Drill overheating
This is one of the most common problems. Overheating can lead to the drill losing its working properties and, as a result, to its destruction. To avoid overheating, you must:
Use the correct rotation speed: slower for hard materials and faster for soft ones.
Use cooling, such as cutting fluids when working with metals.
Take breaks from work to allow the drill to cool down.
Incorrect sharpening angle
The angle is The point of the drill is critical to its effectiveness. An incorrect angle can result in poor chip removal, poor cutting performance and increased drill load. Sharpening drills is a process that requires knowledge and experience. An incorrectly sharpened drill can be easily recognized by the poor quality of the hole and rapid wear.
Excessive pressure
Excessive pressure on the drill can cause it to break. The pressure should be just enough to push the drill forward, but not so much that it breaks. It is important to feel the instrument and material you are working with.
Using a worn or damaged drill bit
Drills lose their sharpness over time and may become deformed. The use of such drills is not only ineffective, but also dangerous, since the risk of breakage during operation increases significantly.
Wrong choice of drill
Not every drill bit is suitable for every material. Carbide drills, for example, are designed to work with very hard materials. Using them to drill into soft materials can result in unnecessary loss of expensive tools.
Failure to take into account the characteristics of the material
For example, when drilling into laminated materials, you must drill with low pressure to avoid damaging the coating. For ceramic tiles, you need special drills, and for metals, you need drills with high hardness and heat resistance.
Lack of preliminary preparation
Preparation before drilling is also key. It is necessary to mark the drilling point, if necessary, use a centering blow or initial drilling with a thin drill to ensure the accuracy of the entry of the main drill.
Ignoring industrial safety
When working with drills, personal protective equipment, such as safety glasses and gloves, should be used. It is also important to ensure that the drilling equipment is in good working order and that the drill is securely fastened.
Following these recommendations will help not only to avoid tool breakdowns, but also to ensure high quality work, as well as personal safety. It is important to remember that each drill requires some maintenance, as well as replacement after reaching the wear limit.
