BASIC LINES AND VIEWS:

1. OBJECT LINE- TO SHOW THE VISIBLE SHAPE OF A PART

2.HIDDEN LINE-TO SHOW EDGES AND OUTLINES NOT VISIBLE TO THE LINE

3.CENTER LINE-TO SHOW THE CENTER OF CIRCLES,ARCS,AND SYMETRICAL OBJECTS AND TO AID IN DIMENSIONING THESE PARTS

4.EXTENSION LINES-EXTENSION LINES SHOW DIMENSION POINTS .DIMENSION LINES TOUCH THE EXTENSION LINES AND SHOW DISTANCE GIVEN BY THE DIMENSIONS.

5.LEADER LINE-POINTS DIRECTLY TO A SURFACE FOR THE PURPOSE OF DIMENSIONING OR ADDING A NOTE .A DOT MAY BE USED AT THE END OF A STRAIGHT LINE WHERE REFERENCEIS MADE TO A SURFACE AREA.

6.CUTTING PLANE LINE-TO INDICATE WHERE AN IMAGINARY CUT IS TO BE MADE THROUGH A OBJECT.THE ARROW POINTS IN THE DIRECTION IN WHICH THE SECTION SHOULD BE VIEWED.LETTERS NEXT TO THE ARROWHEADS IDENTIFY THE SECTION IN THE CASESWHERE MORE T5HANONE SECTION IS SHOWN ON THE DRAWING.THESE LINES ARE ORIENTED VERTICALY,HORIZONTALY,OR AT THE ACTUAL ANGLE AT WHICH THE PART IS DRAWN.

7.SECTION LINE-TO INDICATE THE IMAGINARY CUT SURFACE REFERRED TO BY THE CUTTING PLANE LINE.TO REPRESENT VARIOUS KINDS OF MATERIALS.

8.CHAIN LINE-INDICATES  THE LOCATION AND EXTENT OF A SURFACE AREA.

9.SHORT BREAK LINE-TO SHOW  A SHORT BREAK(TO CONSERVE SPACE ON A DRAWING).TO SHOW A PARTIAL SECTION.

10.LONG BREAK LINE-TO SHOW A LONG BREAK(TO CONSERVE SPACE ON A DRAWING)

11.PHATOM LINE-TO SHOW ALTERNATIVE POSITION OF A PART;6TO SHOW RELATIONSHIP OF EXISTING PART TO NEW PART;TO SHOW MACHINED SURFACE.

OBLIQUE DRAWINGS-TO DEVELOP AN OBLIQUE DRAWING,AN ORTHOGRAPHIC VIEW OF THE OBJECT IS FIRST DRAWN WHICH BEST DESCRIBES THE SHAPE AND SHOWS THE MOST DETAIL OF THE OBJECT.AFTER COMPLETING AN ORTHOGRAPHIC VIEW DRAW PARALLEL RECIDING LINES AT ABOUT 45DEG. ANGLES FROM THE CORNERS OF THE VIEW TO DEVELOP A THREE-DIMENSIONAL EFFECT.RECEDING LINES ARE DRAWN TO THE RIGHT FOR A RIGHT OBLIQUE DRAWING AND TO THE LEFT FOR A LEFT OBLIQUE DRAWING.

ISOMETRIC DRAWINGS-TO DEVELOP A ISOMETRIC SKETCH,ISOMETRIC GRAPH PAPER IS PREFERABLE.AN ISOMETRIC SKETCH HAS ALL OF ITS SURFACES SHOWN AT 30 DEG. ANGLES.IN THE INITIAL PREPERATION OF THE SKETCH,A VIEW OF THE OBJECT THAT BEST SHOWS ITS SHAPE AND DETAIL IS SELECTED AND SKETCHED AT A 30DEG. ANGLE.

NOTES AND SPECIFICATIONS-A NOTE IS LETTERED INFORMATION CONCERNING THE DETAILS OF CONSTRUCTION.THE NOTE EXPLAINS,SPECIFIES,OR REFERS TO THE MATERIAL AND/OR PROCESS NEEDED TO MAKE THE PART.WHEN A NOTE APPLIES TO A PARTICULAR PART ON AN OBJECT,IT IS CALLED A LOCAL NOTE.A GENERAL NOTE APPLIES TO THE DRAWING AS A WHOLE AND IS PLACED IN A OPEN SPACE AWAY FROM THE VIEWS SO THAT IT CAN BE SEEN READILY.

WELD SYMBALS-THE STANDAR WELDING SYMBAL CONSISTS OF A REFERENCE LINE,AN ARROW AND A TAIL.

THERE IS MUCH MORE INVOLVED IN THIS SUBJECT.I HAVE PROVIDED SOME OF THE BASIC INFORMATION ON THIS SUBJECT.