Tutorial 5 - Basic Drawing

In this exercise you are going to draw a very simple shape - a rectangle - in several different ways. The purpose of this is not to create a realistic CAD drawing, but to show you how to draw easily and accurately with the CAD using a variety of methods.

You will learn how to:

• Use specific coordinate locations.

• Undo an operation.

• Use the [Home], [End], [PgUp] and [PgDn] keys.

• The arrow keys.

• Input polar coordinates.

• Use a locked cursor.

• Use geometry.

• Use a grid.

• Use jumps and snap modes.

• Save your drawing.

Setting Up Your Drawing

Ensure your drawing screen is blank by selecting File ► New.

In this tutorial you begin with a blank screen representing a blank sheet:

• A4 paper at a scale of 1:1.

• Units will be millimetres.

• Cartesian mode

• Decimal angular format (dd.dddd) with angles measured anti-clockwise from 3 o’clock.

• Landscape orientation.

1. To set up your drawing like this, select Settings ► Drawing Settings. The Drawing Defaults window displays.

2. Click the button in the Angular format section. The Angular Format window displays.

3.  Edit the settings so they look like the example shown above, and then click OK twice (x 2) to save your changes.

4. Use the Redraw command by clicking the Redraw icon in the Zooms toolbar, or by selecting View ► Redraw.

5. You can change paper size, scale, units, etc. at any time during drawing. See Drawing Settings.

Using Specific Coordinate Locations

You are going to draw your first rectangle in the top left corner of the screen.

1. Click the Rectangle icon or select Draw ► Rectangle.

2. You are prompted to:

3. You are now going to position the first corner of the rectangle at a specific coordinate location, using the Coordinate Jump function. To do this, ensure that your cursor is in the Drawing Area, and then click the Jump Coordinate icon in the Jumps toolbar or select Tools ► Jumps ► Coordinate Jump. Alternatively, press [U].

[U] is called an Accelerator because it is a fast way of accessing the Coordinate Jump function.

4. You are prompted to:

5. Type in the coordinates “-120 80” as shown above, and then press [Enter] or click Enter to accept these coordinates.

6. The cursor moves to the top left part of the screen. Note that the cursor display at the bottom right of the screen reflects the cursor's position of -120 80.

7. You are prompted to:

Click the Jump Coordinate icon again to access the move to coordinate function.

8. You are prompted to:

9. Type over the default coordinates of -120 80 with the coordinates “-90 40”, and then press [Enter] to accept these values. The cursor moves and the rectangle displays. You have now drawn your first rectangle using absolute coordinate positions.

10. You are prompted to:

11. Ignore this prompt for the time being and press [Esc] or [Spacebar] to terminate the function.

An Aside - Undo and Redo

You are now going to Undo the rectangle you have drawn so that if you do something wrong later in this tutorial you can Undo it and try again.

1. Click the Undo icon or use the Edit menu.

2. The rectangle disappears. You can undo a maximum of 1000 actions in this way.

3. If you undo something by accident, you can redo it again by clicking the Redo icon or using the Edit menu.

Using the Home, End, PgUp and PgDn Keys

As you have undone the rectangle you drew, you should now have a blank drawing area.

1. Select the Rectangle function again.

2. You are prompted to:

3. Move your cursor into the Drawing Area. Click the Jump Coordinate icon to access the Move to Coordinate function.

4. You are prompted to:

5. Type “-120 80” and press [Enter] to accept these coordinates. The cursor moves to coordinate position -120 80 in the top left part of the screen.

6. You are prompted to:

You are now going to define the precise position of the second corner of the rectangle using the keyboard.

Accurate horizontal and vertical movement is achieved with the arrow keys.

Accurate diagonal movement is achieved with the [Home[, [PgUp], [End] and [PgDn] keys; and the Polar Jump function.

7. Press [PgDn}. The second corner of your rectangle is below and to the right of the first corner. If you have a numeric keypad, you will note that the [PgDn] key is the bottom right key on the keypad, corresponding to the direction in which you want to move.

8. You are prompted to:

9. Type “30 40” and press [Enter] to accept the distances. The cursor moves to a position 30mm to the right of, and 40mm down from, the original point. The outline of a rectangle appears.

Note that the rectangle outline is not coloured and that AllyCAD is still prompting for the second rectangle corner. This is because while you have moved the cursor to the new position, you have not yet accepted this as the position for the rectangle corner.

10. To accept the position as the second rectangle corner, press [Enter] again. Alternatively you can click, however,you may accidentally move it slightly off the correct position resulting in an inaccurate rectangle.

11. The rectangle becomes coloured and you are prompted to:

When you use the [Arrow], [Home], [PgUp], [End] or [PgDn] keys, you have to press [Enter] an extra time in order to fix the cursor position after the cursor has moved. This allows you to re-adjust the cursor position if you are not satisfied with it. For example, you may want to shift the cursor an additional 10mm to the right before accepting its position.

Using the Arrow Keys

 You are going to draw the next rectangle with lines. You are also going to position this rectangle relative to the first rectangle you drew using the [PgUp] and [PgDn] keys.

1. Ignore the prompt for the first rectangle corner and click the Chained Line icon .

2. You are prompted to:

Indicate start position of line

3. An "x" marks the last point you entered at the bottom right corner of the rectangle. Move back to this point by pressing [X]. This performs a Last Fixed jump and moves your cursor onto the last point you entered. You can also access the Last Fixed jump via the Jumps option on the Tools menu.

4. Press [Right-Arrow].

5. You are asked:

6. The program remembers the horizontal distance that you entered when you pressed [PgDn] key, in this case “30”. Press [Enter] to accept this distance.

7. The cursor moves 30mm to the right. Press [Enter] to accept this position as the first point in the line of your new rectangle.

8. You are now going to draw a rectangle using the arrow keys. You are prompted to:

Indicate end position of line

9. Press [UpArrow].

10. You are asked:

11. The program remembers the vertical distance that you entered when you pressed [PgDn], in this case “40”. Press [Enter] to accept this distance.

12. A vertical line 40mm long is drawn. Press [Enter] to accept this line.

13. You are prompted to:

Indicate end position of line

14. Moving the same distance again, you now need to draw the next line in the rectangle - a 30mm horizontal line. Press [Shift+RightArrow]. You are not asked how far you want to move and the cursor automatically moves 30mm to the left, drawing a horizontal line. The program has remembered the distance you last moved horizontally. Pressing the [Shift] key at the same time as the arrow key has caused it to move this distance automatically.

15. Press [Enter] to accept the new horizontal line.

16. Press [Shift+DownArrow]. A 40mm vertical line is drawn. Press [Enter] to accept the line.

17. Complete the rectangle by pressing [Shift+LeftArrow].  A 30mm horizontal line is drawn. Press [Enter] to accept the last point on the rectangle.

18. You are prompted to:

Indicate end position of line

Using Polar Coordinates

1. Ignore this prompt and click the Rectangle icon .

2. You are prompted to:

3. Move your cursor off the toolbar and onto the Drawing Area. Click the Jump Coordinate icon to access the Move to Coordinate function.

4. You are prompted to:

5. Type “0 80” and press [Enter] to accept these coordinates. The cursor moves to the right of the rectangles you have already drawn.

6. Click the Jump Polar icon to access the Jump Polar function.

7. You are prompted to:

8. You are moving to the opposite corner of the rectangle so you need to give a distance of 50mm and a bearing of -53.13 or 306.87 degrees. Then press [Enter] to accept. The rectangle is drawn.

9. You are prompted to:

This is because you have not yet “fixed” the position of the second corner.

10. Press [Enter] to fix the position, and then press [Esc] to terminate the function. This rectangle is not exactly the same as the others because only two decimal places have been used. However, it serves to illustrate the use of polar coordinates.

Using a Locked Cursor

In this section, only locking the cursor into the horizontal and vertical directions is demonstrated. However, the cursor can be locked to any angle and to its orthogonal, as well as into an isometric mode (30, 330 and 90 degrees).

1. Ignore the prompt for the first rectangle corner and select Draw ► Line.

2. You are prompted to:

Indicate start position of line

3. Click the Coordinate Jump icon.

4. You are prompted to:

5. Type “60 80” and press [Enter] to accept these coordinates. The cursor moves to the right of the rectangles you have already drawn.

6. You are prompted to:

Indicate end position of line

7. Press [Shift+Right-Arrow] to move the cursor 30mm to the right. Press [Enter] to accept the horizontal line that is drawn.

8. You are prompted to:

Indicate start point of line

9. Ensure that your cursor is in Grab All mode. If not, click the Grab All icon on the Snaps toolbar or press [Shift+A].

Do not worry about the fact that the line you are drawing follows your cursor as you click the icon in the toolbar. When you have clicked the icon, move your cursor back to the area of the screen where you are drawing.

When the cursor is a square you are in Grab All mode. This means that the cursor will automatically jump to any point within the cursor box.

10. You are now going to lock the cursor so you can only draw horizontally or vertically. Click the Lock Perpendicular icon in the Lock Cursor toolbar. Alternatively, press [+] on your numeric keypad or select Tools ► Lock Cursor ► Perpendicular.

11. A diamond shape appears inside the box that represents the cursor. Click inside the cursor box and then use your mouse to pull the cursor downwards. The line that is drawn is vertical and straight. When the line reaches the level of the bottoms of the rectangles you have already drawn, move your mouse to the left. The square representing the cursor separates from the diamond. Move the cursor so that the bottom right hand corner of the right hand existing rectangle is within the cursor box.

12. Click and the square cursor jumps back to the diamond shape and the vertical line has been terminated so that it is exactly the same length as the vertical lines of the other boxes. Press [Enter] to accept the line.

13. Now move your cursor through the cursor lock indicator. When you do so, the cursor lock switches between vertical and horizontal.

14. With the cursor movement locked into horizontal mode, place the cursor box around the end of the top line and press [Enter] or click. The cursor box springs back and the bottom line of the box is drawn to exactly the right length. Press [Enter] to accept the line.

15. To finish the box, move your mouse upwards so the cursor box surrounds the end of the top line again. Press [Enter] or click to complete the rectangle.

16. Cancel line drawing by right-clicking  and selecting Quit in the popup menu. Alternatively, press [Esc] or [Spacebar]. When you cancel line drawing, the cursor is automatically unlocked.

Using Geometry

In this section you are going to draw some geometry lines and use these to draw a box. The lines you are going to draw will be very simple.

1. Select Geometry ► Cross.

2. You are prompted to:

Indicate cross position

3. Click the Jump Coordinate icon.

4. You are prompted to:

5. Type “-120 0” and press [Enter] to accept these coordinates. A cross of dotted geometry lines appears at the left of the screen. These lines can be snapped to. They can be turned on and off, rubbed out, and saved. Although you can see them on the screen, they do not plot out.

6. You are prompted to:

Indicate cross position

7. Press [Shift+PgDn]. The CAD automatically moves 30mm to the right and 40mm down, which are the distances you have been using throughout this tutorial.

8. Press [Enter] to accept the new cursor position as the position of the second cross. The second geometry cross displays.

9. You are prompted to:

Indicate cross position

10. Ignore this prompt and click the Rectangle icon .

11. You are prompted to:

Indicate first corner of rectangle

12. Position the cursor near the top left intersection of the geometry lines and then click. The first corner of the rectangle is defined.

13. You are prompted to:

Indicate second corner of rectangle

14. Move the cursor close to the intersection to the bottom right of the geometry lines as shown below. Click to accept it as the second rectangle corner.

15. For the present, you will not need the geometry lines you have drawn. Turn them off by selecting Geometry ► Switch Geometry On/Off or by clicking the Geometry Toggle icon. The geometry lines are not displayed.

Using a Grid

Now, you are going to draw a rectangle using a regular grid.

1. Go to Settings ► View Settings select the Grid Settings option.

2. Set up the grid display with a pale grey colour and an interval of 30 in the X plane and 40 in the Y plane. This yields a grid with horizontal spacing of 30mm and vertical spacing of 40mm. For convenience, specify that the grid will be drawn as lines.

3. Click OK to display the grid.

3. Click the Rectangle icon.

4. You are prompted to:

Indicate first corner of rectangle

5. Press [Shift+G] to activate the Grid Snap mode. Move the cursor to the position shown and click. The cursor jumps exactly onto the nearest grid point and enters the first corner of the rectangle.

6. You are prompted to:

Indicate second corner of rectangle

7. Now move the cursor close to the grid point below and to the right, and then click. The cursor jumps to the grid point and accepts that point as the second rectangle corner.

8. You no longer need the grid so select Settings ► View Settings and uncheck the Grid visible checkbox to switch it off.

Jumps and Snap Modes

Jumps

So far you have encountered four types of jumps/snaps.

There are also a number of other jumps.

In the Grab All and Freehand modes you can use any of the jumps listed above.

Snaps

There are also various snap modes. One of the most useful snap modes is GrabAll snap, which is activated by clicking the GrabAll icon on the Snaps toolbar or pressing [Shift+A].

In Grab All mode, the cursor is a square and automatically jumps exactly to any point within this square each time you press [Enter] or click.

You can specify which points the GrabAll snap will snap to using the GrabAll Settings.

In addition to the Freehand, Grab All and Grid modes, there are also the following snap modes.

Name	Key	Icon	Description
Geometry Intersection	[Shift+I]		Automatically snaps to nearest geometry intersection.
Point	[Shift+J]		Automatically snaps to nearest point.
Nearest Entity	[Shift+N]		Automatically snaps to nearest element.
Intersection	[Shift+Z]		Automatically snaps to nearest intersection.
Circle Centre	[Shift+Num*]		Automatically snaps to nearest circle or arc centre point.
Near Circle Centre	[Shift+E]		Automatically snaps to the centre point of the nearest circle or arc.
Apparent Intersection			Automatically snaps to intersection between entities in 3D space that appear to intersect but are on different planes.
Perpendicular	[Shift+P]		Automatically snaps a line to another line or arc so that they are perpendicular to each other.
Tangent to Circle	[Shift+T]		Automatically snaps a line or arc to another line or arc so that they are perpendicular to each other.
Mid point	[Shift+M]		Automatically snaps to the midpoint of nearest entity.
Ratio	[Shift+C]		Automatically snaps to the ratio of length on entity.

Note that the cursor is a different shape in each mode.

Although Geometry Intersection and Grid jumps and snap modes are used in this tutorial, the Grab All mode can also snap to geometry intersections and grid points, as well as to points and intersections.

Some functions automatically switch to Freehand mode, because it is important that the cursor doesn't snap to anything by accident. These include the Coordinate Jump and Polar Jump.

Visual Snap Indicator

If the visual snap indicator is switched on, the snap points are highlighted with a red rectangle as the cursor gets close to them. You activate the visual snaps by clicking VS in the Status Bar.

You can change the visual snap indicator using the Visual Indicators option of the System Settings.

Saving Your Drawing

You can now save your drawing.

1. Click the Save icon and type “Accurate Drawing” as a name for your drawing.

2. Click Save.

3. Now close the drawing by selecting File ► Close.

You now know how to draw entities accurately.