Crowns for drilling concrete: types and methods of
During repair or construction work for laying communications, it is often necessary to drill a hole in the concrete with a crown of different diameters, depending on the size of the track. But on the wall, for example, there can already be some lining (the same ceramic tile) and then this method of penetration can cause aesthetic harm, that is, damage the edges or even beat the lining.
Below we will tell you how to choose the right cutter, which tool is better to use, and also show you the video in this article on this topic.

Core drilling for concrete
Types of core cutters

Note. The expression of a core bit over concrete is not quite correct, since it no longer applies to concrete, but to metal, since there are diagonal grooves on the outside of such a crown, like the spiral grooves of a conventional drill and they are not used for mineral surfaces. Such tools are more designed for processing wood, plastic or metal.

- In the photo above, you see the most common version of the crown on concrete with a diameter of 65 mm with pobeditovy napayka, which, however, is suitable for many other minerals such as brick, cement-sand and cement-lime plaster, putty, rotband, etc.. The picture shows a bolt of fastening of the centering drill, which can be removed and replaced, but in most cases recently they began to produce cutters with a removable shank.

- In a modified version, the cutter is unscrewed from the shank and wound onto an extension cord, which allows the walls to be penetrated up to a meter thick.. Of course, this option is only possible with a good perforator for concrete, with a powerful torque and a strong blow.
- But diamond drilling of holes in concrete does not need to be hit - it occurs on the same principle as cutting reinforced concrete with diamond circles - by abrasive rubbing of the material being processed. In addition, diamond crown cutters are very useful when there is a facing material on the surface, as well as for drilling large-diameter holes.
- The fact is that when struck, pobedits' taps are not frayed, but, as it were, knock down concrete (brick, plaster) in a circle. It turns out that such a rotation is not constant, and cyclical and keep the tool in the hands with such a load will be too difficult. In addition, from the power of a side impact will break off the victor heads.
Ways of drilling

Now we will talk about how to drill a crown on concrete with different diameters and in different materials. First of all, the person who performs this work, it should be understood that the force of rotation of the tool is large enough, so if you loosen the hold, it can be pulled out of your hands with a torque, and this is still half the problem.
There are cases when clothes were wound on a drill or perforator, knocking down a worker, resulting in injuries, so this process requires constant attention and some training.
Due to the fact that the cutter is equipped with a centering drill, the hole can be made with an accuracy of 1-2 mm - here everything will depend on the density of the processed material - the more it crumbles, the greater the error.
For the correct entry of the crown into the structure, it is important that the punch or drill be in relation to the wall (ceiling, floor) at an exact angle of 90? - safety of work also depends on it - less danger of a sharp jerk.
In general, such a danger is most often found in the brickwork - in the seam the tooth of the cutter goes freely and then stumbles upon a solid obstacle - a brick, from which there is a sharp jerk and the tool needs to be held quite strongly. This is especially true of the electric drill, where the rotational speed is higher than that of the perforator, therefore, the punch and jerk will be stronger.
Recommendation. Such a caution is not an ordinary tribute to safety or a non-binding instruction — the author of this article, having many years of experience, made a hole for the underside of the crown on the STERN drill.
When the cutter went through the putty and the upper layer of the brickwork, it stumbled upon some kind of solid formation in the brick - the blow was so strong that the teeth were broken at anchor, although the drill was new and the hand was sick for several days.

But what to do in those cases when the wall is lined with ceramic tiles, because the victorious crown can simply break it, especially if the tile is of poor quality. Here a diamond crown for concrete will come to the rescue, which can be sold either separately or as a set, where rings from 20 mm to 100 mm are located on one holder, despite the fact that in these two versions the crown itself is different - the drilling quality is from this does not suffer.
And, of course, there is no need for a shock moment at all, but only rotation, so for diamond cutters in everyday life, not perforators are usually used, but electric drills and screwdrivers.
Of course, a few words should be said about diamond drilling of concrete, when a hole is made with a special cutter with a large milling cutter, as in the top photo. Of course, the price of such a hole is quite high (depending on the diameter and length of penetration), but the quality of the hole is very high - its edges are clear and neat.
Conclusion
As you understand, at home the use of a cutter does not make sense - it is easier to order the service from some organization, but the use of diamond and pokonitovyh koronchaty mills with a diameter of up to 100 mm is quite popular. Therefore, you can safely make the hole you need, but do not forget about safety.