a drawing in 1-1/2” scale, like a kitchen cabinet drawer detail. The best way to create consistent line weights and line quality is to keep your pencil or pen perpendicular to the drawing surface and drawing media. This keeps the width of the line consistent. Also, keep a constant pressure as you draw a line type from its start to finish. This takes practice and can be mastered if you focus on creating the line consistently and do not try to rush a drafted document.
Keep in mind the hardness/softness and the diameter of the pencil lead only help control the line weight. You also need to use a consistent amount of pressure on the pencil as you draft to keep each weight of line uniform. If the line seems either too light or too dark try varying the amount of pressure you place on the pencil as you draft. Remember, these drawings are meant to be copied and distributed to a variety of design professionals so the lines need to be crisp and readable.
Lines and Line Quality
Guidelines or Construction Lines (4H to 6H pencil lead in a .3mm mechanical pencil)
The initial lines that you will draw on your paper are guidelines or what some refer to as construction lines. These lines are temporary and used to lay out the page, create the initial shapes, and provide a guide for lettering heights. The line weight for guidelines is to be very light as they should be almost invisible on the finished drawing. They must be dark enough for you to see, light enough to erase lines easily, and barely visible when copies or other form of reproductions are made from the drawing. Using a harder 4H to 6H pencil lead in a .3mm mechanical pencil creates the best guidelines. You can also use a blue lead for guidelines as it will not photocopy.