Board Practice

In order to display good board practice, it us necessary to ude the appropriate drawing instruments. This write up will treat the correct procedure for setting the drawing paper, use of instruments and manipulative methods towards good board practices. Follow carefully the procedures so that you can develop good drawing habits. You must also practice these drawings using correct instruments

Setting up the board

Instruments required for good board practice are:

1. Drawing board 2. Tee square 3. Set square (30°-60°, 45° angles) 4. Pair of compasses 5. Dividers 6. Protractor 7. HB pencil 8. 2H pencil 9. Eraser

Step 1 Drawing Board

Place the drawing board conveniently on the table with the square edge to the left hand side.

Step 2 Drawing paper

Place the drawing paper on the board, leaving equal space all around.

Step 3 paper adjustment

Place the tee square on the paper, and gently slide or move the tee square to the top edge of the paper. Set the top edge of the paper parallel to the edge of the tee square, with the stock of the tee square firmly against the edge of the drawing board on the left  hand side.

Step 4  movement of the tee square

Gently slide the tee square down without moving the paper.

Step 5 Holding the paper down

Cut four pieces of adhesive tape to hold the paper in position, and place them over the four corners of the paper.

Five basic techniques in setting up the board

Drawing lines with a Tee square

All horizontal lines are drawn with the aid of the tee square, usually from the left yo right, and rotating the pencil as the line is drawn. This ensures uniform thickness of the line.

Drawing lines with a set square

The set square is used sitting on the tee square to draw upright or vertical lined on the paper angled lines are also drawn with the set square turned in different directions 

Using pencil with out the aid of any other instrument

The vertical strokes are made by finger movements, and the horizontal strokes are made by pivoting the whole hand at the wrist, while the fingers move slightly to keep the strokes perfectly horizontal.

Drawing a circle with compass

The centre of the circle is first marked. Guide the needle point of the compass to the  centre of the circle with the small finger. The compass is  then inclined slightly in the direction of the stroke.

Incline the compass slightly in the direction of the stroke  and complete the circle by twisting the knurled handle of the compass with the fingers. The stroke is completed to form the circle.

Setting the desired radius with compass and dividers

For accuracy in size of radius of circles or taking dimensions with dividers for scaled drawing, the instruments is adjusted directly on the rule or scale. The dividers or compass is held with one hand and the radius is set by using the thumb and the second finger to gently push the other leg of compass/ dividers to the required size.

Types and use of lines in technical drawing

The different blinds user to make a drawing  are shown below. Through practice you will be able to draw them. The different lines can be called ' alphabet of lines'

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Thick continuous line

--------------------  -- -------------  ---- ------------------

Thick long chain

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -  -

Thin short

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Arrowheads

Thick continuous lines are used for visible outlines and edges.

Thin continuous lines are used as dimension lines, projection lines and construction lines.

Thick long chain lines are used for cutting planes and viewing planes.

Thin long Chaim limes are used as centrum limes and path lines for indicating movement.

Thick continuous wavy or irregular line are used for short break lines and boundary lines.

Thin ruled limes with short zig zags are used for lon break lines.

Thin continuous wavy or irregular lines are used for limits of partial views.

Arrowheads are used at the end of the dimension lines.

Thin short dashes are used for hidden outlines and edges.

Title block

After the drawing had been laid out on the paper , it is necessary to give some information to enable others to understand what the drawing is about. Such information relating to size (scale) , name of object , name and date of drawing is put on what is known as the title block. The title block is usually at the bottom right hand corner of the drawing paper.

To letter a title block

The title block should be letterer free hand on single stroke capitals. Only one method of  lettering  should be used, vertical or inclined, not both styles in the same drawing title.