Any arch represents a part of a circle. To construct an arch on paper happens it is necessary not only at a school lesson of geometry. The designer of clothes when modeling a pattern can face such task or the worker who should adjust already calculated detail. Modern engineers most often perform such tasks by means of special computer programs. But the principle of construction a little in what differs from that which is used at a usual school lesson.
It is required to you
- - circle radius length;
- - sector corner;
- - compasses;
- - protractor;
- - ruler;
- - pencil;
- - computer with the AutoCAD program.
Instruction
1. To construct an arch, it is necessary to know 2 parameters: radius of a circle and a corner of the sector limited to an arch. If these parameters are not set in a task, they need to be found. It becomes depending on conditions. For example, the parties or corners of the inscribed in a circle or described about it polygon can be given. By means of necessary formulas calculate the radius size.
2. Draw a piece which length is equal to circle radius length. Designate one of its points as O. Eto will be the center of a circle from which and it is necessary to plot an angle. This radius can be drawn in any direction.
3. Combine a zero mark of a protractor with center O. Postpone the corner equal to a corner of the sector and put the end. Connect this point to the center of a circle. Continue a piece in the direction from the center at any length. On it it is possible to postpone the radius size though to do it and it is not obligatory as you already have one radius.
4. Put a needle of compasses in the center of a circle, and it part legs on radius distance. Carry out an arch before crossing with the second radius.
5. Much more opportunities for creation of an arch give the computer. It is the most convenient to use the AutoCAD program for this purpose. Creation of an arch on a point of the center, radius and a corner — only one of opportunities. In this program the arch can be built on three any points, on points of the center, the beginning and end, on chord length. Everything depends on what data you have.
6. Find a tab with the inscription "Main" in the top menu. There you will see the Drawing panel, and in it — to a panelk "Arch". Open this panel, and you will see the whole list of data according to which it is possible in this program to construct an arch. Look what data you have and choose the necessary line. For creation of an arch on three points specify them consistently by means of the cursor. Designate the necessary points with the right mouse button.
7. For creation of an arch in the parameters including the size of a corner or length of a chord it is necessary to open a context menu repeatedly. That is at first define a point, the center, then again open the menu and find in the section "Arch" "Corner" or "Chord". There will be a plate into which it is necessary to enter value of a corner or length of a chord and to press Enter.