| A | B |
|---|
| visible or object lines | solid, continuous, heavy lines that show straight, curved, and circular objects |
| hidden lines | dashed lines (- - - - - ) that show the positions of objects that can't be seen because they are behind other objects |
| section lines | thin lines at a 45 degree angle that show the interior features of an object that has been cut away |
| dimension lines | thin solid lines that show the distance between particular points |
| leader lines | arrows that point to an object or a point |
| extension lines | lines that show the beginning and end of dimension lines to show what the dimension lines measure |
| cutting plane lines | thick broken lines that show what is exposed when we mentally cut through a part. |
| break lines | these can shorten drawings when the details don't change, or they can show a cross section or detailed view of a part |
| phantom lines | a long, two short, and another long line that shows alternate positions for parts, movement of parts, or the position of parts that are absent |
| dimension A | from overhead to the top of a flat part |
| dimension B | from overhead to the bottom of a flat part |
| dimension BP | from deck to the bottom of a round pipe |
| dimension C | from the bulkhead to the side of a flat part |
| dimension D | from the deck to the bottom of a flat part |
| dimension H | from the deck to the top of a flat part |
| dimension X | from the overhead to the center of a round part |
| dimension Y | from the deck to the center of a round part |
| dimension Z | from the bulkhead to the center of a round part |
