Stainless Steel Hole Drilling
The question of how to drill any stainless steel at home usually does not arise if you use special drills for stainless steels for these purposes. Along with such drills that allow you to quickly and efficiently form a hole of the required diameter, it is necessary to use special cooling compounds, as well as strictly maintain the technological parameters.
In production, stainless steel is used for drilling industrial machines with coolant supply. In the home workshop you have to learn some tricks.
Lubricants
Drilling holes in stainless steel products with a conventional drill may fail. This is explained by the fact that steels belonging to the category of stainless steel are distinguished by increased viscosity, therefore, their drilling, especially performed at home, is accompanied by significant heating of the cutting tool and, as a result, its failure.
In order to quickly and efficiently drill a stainless steel, taking into account all of the above, it is necessary to use a cooling material, which, in addition, must have good lubricating properties.
If it’s often necessary to drill a stainless steel, it makes sense to equip the machine with a home-made liquid lubricant supply system (an automobile pump is suitable as a pump)
The most common composition used as a coolant and lubricant for drilling holes in stainless steel is a solution consisting of machine oil and sulfur. To prepare such a solution, both colloidal sulfur and fumigation sulfur, which is often called the "sulfur color", can be used.
In the event that the sulfur at your disposal is a fine powder, it can be immediately mixed with machine oil without special preparation. If you purchased lump sulfur, you must first grind it.
It is possible to make drilling of stainless steel products more efficient if a lubricating-cooling mixture consisting of sulfur and fatty acids, which can be obtained independently at home, is used to perform such an operation. To do this, do the following:
- grind a piece of laundry soap (you can use the cheapest);
- mix the crushed soap with hot water and mix the resulting mixture thoroughly;
- add technical hydrochloric acid to the resulting solution;
- wait until fatty acids begin to rise on the surface of the resulting solution;
- then add a large amount of cold water;
- remove the hardened barrel of fatty acids from the surface of the solution, which are subsequently used to prepare the lubricating-cooling solution.
The fatty acids obtained in the preparation of the drilling fluid are mixed with sulfur in a ratio of 6: 1. Using a solution made according to such a recipe, it is easy to drill a stainless steel product, which differs even in significant thickness. Naturally, when performing such a procedure, certain technological recommendations should be adhered to.
Видео: Stainless Steel Hole Drilling
Useful Drilling Techniques
There are several simple techniques that allow you to quickly and efficiently drill a hole in stainless steel. We list the most common of them.
- Drilling horizontal surfaces from a stainless steel is best done by first passing the drill through a lubricant and coolant poured into a rubber washer or plastic plug installed directly above the location of the future hole.
- If you need to drill a hole in a stainless steel surface located vertically, then in the place of drilling you can fix a ball made of paraffin, which will provide lubrication to the cutting tool.
- Regardless of whether you will drill a stainless steel using a household electric drill or industrial equipment, it is better to carry out such a technological operation at low revolutions of the cutting tool (100–600 rpm). Using even a very high-quality fluid for lubrication and cooling will not be able to provide a high-quality result of drilling stainless steel, carried out at high speeds.
An indicator of the correct selection of the drilling speed of a stainless steel is a long chip
In order to get a more detailed idea of how to properly drill parts from stainless steel, you can study this process by video.
There are no problems with drilling at low speeds if a machine or drill is used for this, on which the option to adjust this parameter is provided. If there is no such option, then you can drill a stainless steel as follows.
- An electric drilling tool starts in just 1–2 seconds.
- After a short start, the drill immediately turns off.
Such a simple technological technique allows to provide low rotational speeds of the cutting tool, which, in fact, is required for high-quality drilling of stainless steel.
Drill selection
If you need to drill a product from stainless steel, the choice of a drill along with the selection of the appropriate lubricant and coolant, as well as the technology for performing the operation, is the most important procedure that determines the quality of the final result. Until recently, cobalt drills were used to drill stainless steels.
Cobalt drill for drilling stainless steel, cast iron and heat-resistant steels without prior alignment
Cobalt drills, which were equipped with cylindrical shanks, were produced from P6M5K5 alloys, and in some cases from P18 steel, in which the amount of cobalt was limited to 5%. The advantages of drills made of an alloy containing cobalt in their chemical composition are that this chemical element gives the tool high hardness, which allows it to easily drill any product from stainless steel. The normative document in accordance with which such tools were produced was GOST 10902-77.
Today, these drills are no longer manufactured by industry, and finding them on the market is not easy. Meanwhile, modern manufacturers produce many analogues for working with stainless steel, the quality of which is at a high level. If you choose from such tools, you can pay attention to foreign drills, which bear the marking of HSS-Co. They are produced according to DIN 338 and are made of steel, which contains at least 5% cobalt. In fact, the material from which they are made is an analogue of alloys of grades P18 and P6M5K5.
A characteristic feature of a cobalt-added drill bit is a blunt sharpening angle to facilitate alignment at the start of drilling
Sharpening of the cutting edge of the drill varies for soft and hard metals
If you need to drill a hole in a stainless steel, use a few recommendations that will allow you to perform this procedure without any problems.