1 Point Perspective All lines go back to a vanishing point (VP). The vanishing point (VP) can be placed anywhere and it represents your eye level, so if the point is high as in the above animation, you look down on the object. If the VP is low, you will look up underneath the object.
2 Point Perspective The animation above shows 3 blocks being drawn in 2 point perspective. The top block is seen from beneath as the vanishing point (VP) is below it. The middle block is on the VP which means you cannot see the top or bottom. We are looking down on the bottom block as the VP is set high for this object.
Test yourself http://www.technologystudent.com/pdfs/persp14.pdf http://www.technologystudent.com/pdfs/persp1a.pdf
Isometric drawing is way of presenting designs/drawings in three dimensions ISOMETRIC DRAWING In order for a design to appear three dimensional, a 30 degree angle is applied to its sides. Sometimes Isometric grid paper is used to aid the drawing. NOTE: THERE ARE NO HORIZONTAL LINES!
http://www.technologystudent.com/pdfs/isomet7.pdf Test yourself
3rd ANGLE ORTHOGRAPHIC PROJECTION Orthographic drawing is a way of drawing a three dimensional object. Normally the object is drawn as three separate, related views - Front View, Side View and Plan View. Usually the scale of the drawing is written near the symbol, keeping important information together. The symbol identifying third angle projection is seen opposite. This should be placed on every third angle projection orthographic drawing so that the person using the drawing understands immediately the system being applied
Test yourself http://www.technologystudent.com/PDF3/orthog1.pdf http://www.technologystudent.com/PDF3/orthydrw1.pdf
DIMENSIONS RULES Dimensions (measurements) Always use millimetres to dimension your drawing and write the number only.......... Numbers are always written above and in the middle of the dimension line.............. All vertical dimensions written to the left of the dimension line (these are always read from the right hand side of the drawing)