Axonometrical projections are necessary for the image of an object on the plane from different positions of observation. Most often they are used on the subject "Drawing" at schools and HIGHER EDUCATION INSTITUTIONS. Therefore knowledge of construction will help with an axonometry to many future engineers and designers.

## Instruction

1. The image of a circle demands auxiliary constructions. In this case it will be a square which in the plane of display becomes a rhombus. Creation of a rhombus with sides which are parallel to projection axes has to become your first action. Length of its parties is equal to diameter of a circle, the center of a figure is also the center of a circle. Note points of A, B, C, the D rhombus. Among them there is A point – the closest to the place in which projection axes meet.

2. Represent two diagonals. AC is a small diagonal of a figure, BC – big. The point of intersection of diagonals of a rhombus which, usually call O point it and is the center of the entered and described figures. Draw through the main point of O, straight lines parallel to axes. Designate points in which these straight lines meet with the parties of a rhombus as E, F, G, H. And E goes after A. Draw lines between points of C and E, connect A and G.

3. Note points of I and J which correspond to points of intersection of EC and AG with BC. Use compasses for the image of the arch connecting E point to F. This arch is a part of a circle with the center in a point of I. Radius of a figure is equivalent to EI piece. Use a similar method to connect G and F.

4. To finish drawing of a figure in the projection plane, it is necessary to represent two segments of a circle. One of them has the central point in A. Carry out by means of compasses a part of a circle between points of F and G. Length of AG corresponds to the radius of the first figure. Carrying out an arch between points of H and G will be the last stroke. The point of C at the same time undertakes the center of a circle, EC is equivalent to its radius. Thus, having made simple manipulations, you receive desirable result – the drawn **circle** on one of the planes of an axonometrical projection.