WITH ONE CALL

In your journal in one of the rooms of yesteryear has published an article — “the plug”. I must say that the proposed options combined metal dowels rather complicated to manufacture, but their use is justified for hollow panels and panels of partitions, which in modern buildings are not too frequent. Novosel is usually found with the need to drill or punch holes in concrete, brick and rarely in gipsolitovye panels, and requires significant skills, experience and special tools. Besides produce during operation the noise causes discomfort to the neighbors.

This had to be me, and not once in recent years. So was looking for a way to make this work, to accelerate it and to make it less noisy, knowing how she exasperated neighbors.

The fact that a commercially available coiled and feather drill can drill into the wall just as the abrasion of concrete or brick, the Central part of the drill. This requires frequent cleaning of the hole, a strong pressure on the tool and a long drill. The process is very slow, because the working part of the drill cuts every grain of sand thin “layers” until you turn it to dust. Soon the cutting edge get dull and boring, in fact, terminated, etc — is the abrasion of the stone. We have to stop the drill and break the Central part of the hole punch or periodically to drill a thin drill bit to a depth. And so a few times with each hole.

The main requirement to drill in concrete — it should not be cut very thin layers of each grain, and “destroy,” chopping them. It is easier to carry out drill with the diamond grains. Such drill called “the dream of the settler” produced by the plant of diamond tools in the city of Terek, Kabardino-Balkar ASSR. The kit “Dreams…” was a part of a cylindrical annular drill bit and feather.

Unfortunately, both drill “the dream of the settlers” are not, as the annular drill bit has a diamond grain only at the end part of the surface and has them on the outer edges and Central holes, and drill deeper than 3 to 4 mm into the concrete is not. A first auger has grain in the center, rests on the concrete, sliding it deeper and also 2 — 3 mm into the concrete is not. If you increase the pressure and duration of the drilling they are strongly heated. Besides, sales are rare: probably discontinued, as completely unsatisfactory.

Fig. 1. A standard drill with a carbide insert (A) — for drilling holes in concrete and brick

Fig. 2. Streamline drill (B) — with a notch in the carbide insert

I would call and drill bits for concrete other types, appears in the sale, but their design is as ill-conceived. For example, the groove — smooth rod with a selected groove, which quickly and tightly clogged and requires after each 2 — 3 mm speed drill to clean this groove. It’s amazing that for many years toolmakers can’t create a good drill for domodelov and Novoselov (on concrete and brick).

I think many will be interested in my experience. Offer, for example, to change the configuration of the drill bit with a carbide insert, so that quickly, with one call to drill in concrete or brick wall hole to the required depth.

Diamond needle file I made a slit at the Central part of the drill to a depth of 1.5 — 2 mm and width 2 — 3 mm for drill diameter 8 mm. In this case the drill works like the ring. The resulting conical core of concrete abraded faces or cut breaks off, as propyl steel. More convincing usefulness is cut, if the hole is pre-drill 2 — 3 mm drill bit. In this case, rassolova to 8 — 10 mm obtained in seconds, even in conventional drill bit, without carbide inserts.

Unfortunately, not every domodel or Novosel has a diamond needle file. Therefore, it is desirable that such propyl (these drills) would be doing industry with the help of diamond disc.

M. LEVIN, G. s a n t-P etersburg