Not only soft metals (copper and aluminum alloys), but also steel and cast iron are subject to high-quality tools. This fitting threading tool will allow at home, without the presence of sophisticated equipment and professional skills, to produce a nut, bolt or stud. It is divided into two types:
For cutting internal threads (nuts, holes, sockets, body parts, etc.) a tap is used.
For threading external threads (bolts, screws, studs, shafts, etc.), a die is used. Also with the help of the gauge, such work can be performed on the pipes.
For high-quality manufacturing of threads, not only the blank, but also the cutting tool itself needs to be fixed. Therefore, the master must have accessories:
Plash holder – for fastening leerok.
Vorotok – for mounting taps.
It should also be remembered that the thread is classified according to several parameters:
External and internal.
Metric and inch. The main difference is that the first has a deeper profile. It greatly weakens the pipes, making their walls thinner. Therefore, in such cases, dies are used for the manufacture of inch threads (another name is metric).
Big and small step. The distance between adjacent turns of the groove (or ridge).
Left and right (direction of rotation of the cutting tool).
Depending on these parameters, thread-cutting tools are also created. But given the factor that when working on metal workpieces with large diameters, it is necessary to put considerable effort. And if the strength of human hands can be increased by using long handles of cranks and die holders, then securely fix the round part in a vice, with such loads, will not work. Especially if you take into account the undesirability of its deformation. And for hollow billets (especially pipes), this becomes impossible. Also, heavy loads can lead to breakage of the cutting edges and tool teeth.
The way out of this situation is the use of special sets of dies and taps. When cutting a large-diameter thread, the tool with number 1 is first passed, and then with number 2. The corresponding marking will make it possible to distinguish between “rough” and “finishing” views.
Each type or subspecies of the thread-cutting tool requires its holder. If the situation with the knobs is simpler, one copy is enough to fix a large range of taps, then with the holders it is much more expensive. For each size Lerka need its own clip. For several dies – a whole set of holders.
Therefore, buying a thread-cutting tool in special or building stores, it is necessary to take into account the factor of availability and price of the respective holders.