Drill attachment, enabling drilling holes in brick and concrete walls faster and much easier than forging them by hand, it is only indirectly related to the processing of DIY materials, however, it is hard not to mention, given: first, home workshop device, a po drugie, hanging on the walls or connecting with them with screws and hooks of various structures.
Special carbide drill bits are required to drill holes in concrete, i.e. from the so-called. widii. The tip of such a drill with caps is shown in the figure,
while the cross-section of the cap in the drawing.
It consists of a body (1), inside which there is a driver (2) mounted on an axle (3) ended with a thread (7) – same as drill axis. A three-jaw chuck is screwed onto this thread after the socket is connected to the drill. On the axis (3) a toothed rim is embedded (5), while in the body (1) the same wreath (4). The teeth of both rims face each other yes, that the pressure of these elements causes the teeth to contact each other. Of course, they have an appropriately selected shape, so that both rims can turn in relation to each other. This rotation is done with forcing a little, vibrating axial movement of the rim mounted on the axis (3), with her and the drill, of course, which, turning around, hits concrete with a frequency many times greater, than the spindle speed of the drill. The return movement is provided by a spring (6).
Drilling performance depends on the quality of the drill blades, rotary speed of the drill, pressure on the drill, and hence – pressure on the drill, and the hardness of the drilled element.
In practice, we have no influence on the first factor – we will not sharpen a dull Widia drill ourselves. On the other hand, the rotational speed of the drill depends on the diameter of the drilled hole. If we use a drill with a diameter of up to 8 mm (factory data), then you can drill holes on 2 drill gear. Larger diameters, 9 or 10 mm, fidgeting on 1 running. In practice, however, we advise against using 2 gear for drills with a diameter greater than 6 mm, as the drill and attachment get very hot during use. And let's remember, overheating may result in complete destruction of the tool.
The pressure on the drill is a very important factor. We should always try, to increase this strength, while reducing the rotational speed. Of course, this will not always be possible. Like for example. press the drill firmly against the wall while standing on the ladder? Too much pressure can only lead to the ladder toppling over. So you have to balance the pressure here. For this, first of all, you need practice.
And finally, the last factor influencing the final effect of the work. Well, when we drill holes in bricks. Worse, when we go to the concrete wall, which often find very hard stones used to make the mortar. But it is a tragedy to come across a flint. In such a situation, which we will know after the ineffective, multi-minute drilling, or we give up and drill a new hole in the neighborhood, or, which is sometimes necessary, we will continue drilling, using the thin concrete punch alternately (with a diameter equal to the diameter of the drill) hit with a heavy hammer (weighing at least 1000 g) and drills. After a long time, we will usually be able to crush such a pebble and the hole will be ready. Sometimes the drill will miss the hard stone and distort the hole.
If you come across a rebar while drilling, what we will know when the deepening of the hole stops and small steel filings, which gather on the slightly magnetized end of the drill bit, we have to change the Widia drill bit to a regular steel drill bit with a slightly smaller diameter and risk destroying it (in case the rebar is not located directly in front of the axis of our hole) drill through the reinforcement, and then continue drilling into concrete.
By drilling larger diameter holes, e.g.. 8 whether 10 mm, keep in mind, never hold the drill with both hands on the pistol grip, because if the drill bit is blocked in the hole, the drill will jerk violently, which can even break your arm. So it's best to use an additional one, side handle, mounted on the throat of the front part of the body, and hold the power drill with one hand on the handle, and the other for an additional handle.