Stainless steel is widely used in the construction industry, allowing the construction of durable and strong structures without the risk of corrosion damage. However, the strength qualities and, in general, the physical characteristics of such alloys create many problems at the stage of installation activities, when spot metalworking is required. For example, the creation of holes is one of the most popular operations of this kind, which allows you to prepare technological zones for future fasteners.
Accordingly, the question arises of how to drill stainless steel? The task is not easy and requires the use of a special tool. Also, the technique of directly performing work requires the performer to know certain nuances of the process.
Which tool to drill?
To begin with, the type of tool is determined, which can be used to perform such an operation efficiently and safely. If we are not talking about production, where the use of a drilling machine would be fully justified, then the choice will be between a drill and a puncher. Of course, the eye of the inexperiencedthe user will immediately fall on the puncher, as on a more powerful unit. But not everything is so obvious.
Indeed, an average hammer drill will be much more productive than an electric drill, but it also has a more massive body, has an impressive mass and, in principle, focuses on working with brick and concrete.
How to drill stainless steel with a hammer drill? You will have to work in initially uncomfortable conditions, since the massive design will not give room for maneuverability, and this is the key to successful processing of hard alloys. The emphasis will be on the physical stabilization of the tool, which can not do without an additional side handle.
As for the drill, then, of course, the emphasis should be on professional models with a sufficient power reserve - at least 1500 W in the case of networked devices, and from 18 V if you need a cordless tool for remote work. But in both cases, the design of the drill is optimal for working with stainless steel. By the way, in addition, it would not be superfluous to provide a useful set of functions - electronic speed control, a switch lock button and a reverse run.
Choosing the right drill
It is advisable to give preference to cob alt drills made of high-speed steel alloys of the HSS (M35), HSSCo5, R6MK5 and other grades. The purpose of such equipment is to make holes in hard-to-cut and stainless blanks.
For example, the R6M5K5 drill contains 5% cob alt, which significantly increases the red hardness of the product. In other words, the incandescence of the drill withcritical overheating can occur only if the established standards for the time of the working session are exceeded, but not in the usual regular drilling mode. At the same time, even intensive use of the element will not reduce its wear resistance and hardness. These qualities can be explained by the special production technology of the grinding method, which eliminates the internal stress of the metal.
Drill design parameters: what to consider?
The working part of the drill can be performed in different ways, depending on the required cutting technique. For example, spiral models have a shank with helical edges and grooves that guide chips. This is a universal option for domestic work, characterized by reliability and decent drilling quality.
As an alternative, a step drill can also be offered, but it is more suitable for industries where it is required to make several holes of various sizes in short periods of time without changing equipment.
You should also pay attention to the stainless steel drill sharpening angle, which can be from 100° to 140°. What angle would be best? For steels, it is better to choose models at 130-140 °. Lowering this indicator makes the drill suitable for soft materials like duralumin and brass.
Choosing a drill by shank type
Since the equipment will experience increased mechanical stress due to vibrations during operation, it is important to consider the type of connection with the chuck. mostthe key-type cylindrical hitch is common. In particular, HSS metal drills from Inforce are calculated on it, having a tensile strength margin of up to 900 N/mm2. According to experts, the transmission of torque in this design is not the most successful, but you do not have to worry about the risk of jamming.
Another version of the shank is hexagonal. In this case, fixation is provided by a three-jaw chuck with rigid positioning of each face. The mount is reliable, but the mechanics of handling such equipment is quite difficult. If you need to perform serial drilling, then changing the nozzle will cause a lot of trouble.
Preparation of cutting fluids
High-performance machining of metal alloys is accompanied by increased loads with temperatures brought to critical values. To minimize these effects, lubricants and coolants are used for drilling under load. In this part, two points must be foreseen - the mechanics of the composition itself and its recipe.
As for the first, in one-time events, you can wet the work area manually as it heats up. Automatic systems are usually implemented in the form of a pump connection - for example, from a car pump. The optimal composition of the mixture will include a combination of engine oil and sulfur. As an additional modifier, you can also use technical additives that increase the viscosity of the oil.
Drilling process
The tool immediately adjusts to low or medium speeds, as stainless steel does not tolerate high speeds - this can damage the edges or the drill. The workpiece is installed on a firmly fixed base. It is advisable to use a metal workbench with a vise. Direct mechanical contact is performed only at the moment when the optimum speed of the drill is reached. Then start cutting.
Cob alt drill on stainless steel is directed strictly perpendicular under light pressure. No deviations or jerks are allowed. Moreover, even stops are not desirable, since a failure in the pace of movement will, in principle, negatively affect the structure of the hole. The process is completed with the support of the initial revolutions. Decreasing the speed and turning off the machine is done only after removing the drill from the hole.
Features of working with hardened stainless steel
There are often situations when hardened metal does not lend itself even to drills based on HSS format cob alt. This usually applies to sheets with a thickness of more than 6-7 mm. How to drill stainless steel in this situation?
The way out will be either the use of diamond crowns for cutting glass, or the use of a nozzle with a fine-grained alloy and soldering. The second option is offered in the Bosch line. German developers release a unique line of Multi Construction with a distinctive feature in the form of a blue belt on spirals. This type of drill, thanks to the centering point and AWB soldering, can even handle hardened stainlesssteel.
Features of working with stainless steel railings
Difficulties in working with such a design are due to the round shape of the handrails, and sometimes the presence of special chrome coatings that make it difficult to center the same. The task of the master will be to securely fix the pipe with a vice, as well as in a special drilling tactic.
How to work with stainless steel railings? First of all, the cut point is indicated. This is done with a punch and a hammer. With a light blow, a hole is outlined from which the material will be processed. Then any small-format drill is taken.
At this stage, it is only important to slightly deepen the point at low speeds. Moreover, the end of the drill must be lubricated with machine oil. Then a hole of the required size is formed in two passes with a full-size cob alt nozzle.
Drilling Safety
The main operational factors that increase the risk of injury are electricity and vibration. Electric shock is deadly, so it is important to always control the position of the cable. In no case should it fall into the working area. And initially it is better to give preference to drill models with double electrical insulation.
Then another question - how to drill stainless steel with minimal discomfort from vibrations? The fact is that long-term and systematic work with a construction tool, precisely through strong vibrations, ultimately affects the state of the nervous system, vision and respiratory organs.
The output will be the use of a standard vibration damping system, as well as the installationadditional spring devices on the body. For example, articulated dampers create a cushioning effect that virtually eliminates perceptible vibrations.
General recommendations for the course of work
Much in the workflow will depend on the specific conditions and characteristics of the instrument. But there are also universal rules for performing critical drilling operations that experts recommend:
- Lubrication control. Rapidly draining oil will not give the desired effect. To stabilize it, you can pre-develop a "bath" around the hole and then throughout the entire working process the drill tip will be in optimal condition.
- Use the functionality of the drill. Do not ignore the reverse stroke and the regulation of high-speed modes. There are situations when they not only make work easier, but also prevent unpleasant situations.
- The subtleties of drilling stainless steel when creating through holes. In situations where the drill comes out from the back side, a burr (blocking of the cutters on the edge) may appear. To avoid such a wedge, the initial support of a wooden block under the drilling point from the outside will help.
Conclusion
A quality power drill, paired with a properly sized drill bit of the right diameter, is more likely to meet expectations in creating a hole of the right size. But how much will such an event cost if it is performed at home without helpspecialist?
Cob alt or Pobedit drills for stainless steel are estimated at about 150-200 rubles. An electric drill will cost about 3-5 thousand rubles. Moreover, it is worth choosing in the families of manufacturers at the level of the same Bosch company, for example, Makita, Metabo or Hitachi. By the way, drills can be safely purchased in the same lines.
