Annotations are every object in your drawing which is not a model or geometry.
We use it to show dimensions, text as description, symbols, and pattern to show sections, materials, etc.
The problem with annotation occurs when you need to represent your drawing in different scales.
Let's say we have two images that are the same model in different viewport, with different scales.
If we draw the model and prepare it to a certain scale, say 1:100, when we need to represent the drawing in 1:200, the text, hatches, and all other annotations will be shown in half size to what we expected.
Change your active scale from annotation scale list. It’s on your status bar.
Change it to 1:100. We are going to set our drawing for 1:100 first.
Now open your dimension style. Type “DIMSTY” and press enter.
You should see a style named ’1-100 3mm’. Right click on it, and rename it to ’3 mm’.
Click modify button on the right side of this dialog box.
On the FIT tab, scale for dimension features section, activate annotative.
On the Text tab, change text height to 3, offset from dimline to 1.
On Symbols and Arrows tab, change arrow size, center marks, and break size to 2.5.
Click OK and close the dimension style dialog box.
You see all your dimension text and arrow too small?
Don’t worry. We need to update them to apply the changes.
Autocad will prompt you to select objects, type “ALL” and press enter.
Now we are going to add another scale to these dimensions.
Activate ‘automatically add scales in annotation scale group.
Change the annotation scale to 1:200.
You should see the dimension size adjusted for 1:200 scale.
Turn off the ‘automatically add scales…’ again.
Try to change it to 1:50. What happen? Nothing.
Open your layout. Select the left viewport border, and change the scale to 1:100.
Press [esc] to deselect the viewport. Select the right viewport, and change the scale to 1:200.
Compare the dimension size on those two viewport.
Even the viewports have different scales, the dimension size will always be the same.
When you plot this sheet, the text in all viewports will be 3mm.
The same thing works for Text Styles, Leader Styles and Table Styles.
Once you set these up you can just select the scale and watch all your Dimensions, Text and Leaders go to exactly the right size.
I hope this post helps.