How to Scale your drawings correctly

Question

How do I draw to scale in CAD?
I am used to drawing on paper at 1:50 or 1:100 or 1:20 on an A1 or A2 size drawing sheet but the instructions in the CAD tutorials  tell me to draw everything at 1:1 (true scale). Help i am confused.

Answer

This is one of the most common questions for new users of CAD software. You are right, typically everything should be drawn in CAD at 1:1 (true scale). This prevents you from having to calculate anything – just draw at its true size.

There are 3 ways to work with the software, Methods 1 and 2 are preferred. Here they all are in detail.

Method 1

This is the preferred method for power users.

  1. In a ‘model view’ (e.g. the TOP view) draw all your line work at 1:1 (true scale). i.e. If a line representing a wall is 1203mm long in real life, enter it in CAD as 1203 (assuming you have units set to mm)
    Zoom in and out to fit the drawing into your view as much as you like – Zoom Scale does not affect the actual size of the object, it only changes how big it looks on screen, just like a zoom lens on a camera.
  2. Set the View Scale (the ‘Eye’ Icon then the ‘1:100′ Icon) to the scale value you want to print this view at. eg 1:50 or 1:20 or 1:100 etc. This will ensure that text and dimensions display at the correct size relative to the rest of your drawing.

  3. Create a Composed Drawing view – and select the desired sheet size and Title Sheet file from the supplied library (or one you have created and saved yourself). This Composed Drawing view is a representation of a drawing sheet at 1:1
  4. Now insert your desired model view (e.g. TOP view) at the desired scale using the Add View to Composed Drawing command.

    Note: You can place several model views into the Composed Drawing at different scales if desired. This allows you to add detail views or large scale overviews. Each inserted view can have different layers switched on or off.

    This places a viewing window of the model view into the Composed Drawing sheet view. You can’t edit the model from this composed view but any changes you make in the Model view are reflected in this Compose Drawing view.

  5. Add text and image files to this Composed Drawing view. You can also edit the text in the Title Block that is on this view too. You can also choose to add more Model views and line them up on the sheet.
  6. Print the Composed View using File>Print-Preview>Window 

Method 2

This is a simple method for beginners who are only working in 2D, and only have one scale on the drawing sheet.

  1. In the TOP view draw all your line work at 1:1 (true scale). i.e. If a line representing a wall is 1203mm long in real life, enter it in CAD as 1203 (assuming you have units set to mm)
    Zoom in and out to fit the drawing into your view as much as you like – Zoom Scale does not affect the actual size of the object, it only changes how big it looks on screen, just like a zoom lens on a camera.
  2. Set the View Scale (the ‘Eye’ Icon then the ‘1:100′ Icon) to the scale value you want to print this view at. eg 1:50 or 1:20 or 1:100 etc. This will ensure that text and dimensions display at the correct size relative to the rest of your drawing.

  3. Use the Insert Figure by Origin Point command and select the desired Title Block figure from the supplied library (or one you have created and saved yourself).

    Before Inserting the figure, set the X and Y scale of the figure you are inserting to the desired Print/Plot Scale. It should match the scale you have set the view to. e.g. If the View Scale is 1:50 then the scale of the title block figure should be x=50, y=50, (z=1)

    Locate the Figure over the top of your drawing. If you’ve chosen an appropriate scale then the drawing will fit neatly inside the boundary of your title sheet.

  4. Use the Explode Entity command (dynamite Icon) to explode the title block figure so you can edit it or change the text in it.
  5. Print the View using File>Print-Preview>Selection and enter the scale value before placing the print preview boundary rectangle on the view

Method 3

This is the poorest method for users as it does not take advantage of the computer’s calculation abilities and forces the user to think in the same way as they would when manually drawing.

  1. Create a Composed Drawing view and draw everything to scale as if you were drawing on a piece of paper. (so if line representing a wall is 1203mm in real life and you want to draw at a scale of 1:50 then insert the line at 24.1mm)
    Using this method will also mean you must set the dimension defaults to scale at 50 so that the dimensions scale the drawn line up to the real world value.
  2. Print the Composed View using File>Print-Preview>Window