How to set the scale of a drawing in AutoCAD
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When using AutoCAD to create engineering drawings, the general procedure is to first convert the actual engineering data into a computer-based representation of the desired diagram within the AutoCAD drawing system. Based on the actual conditions, various elements are then added to or edited in the diagram to produce a comprehensive drawing. Finally, this drawn diagram is printed out using a plotter or printer, thereby achieving the graphical representation of the engineering design intent. However, in practical applications, since users focus primarily on editing and refining the graphics, they do not pay enough attention to understanding the relationship between the data obtained from actual measurements and the computer-generated graphics, as well as the relationship between those computer graphics and the final printed output. As a result, it is often difficult to represent the scale of the graphics accurately and effectively. In such situations, the common solution is to use a linear scale, thereby using relative relationships to explain the relative lengths and spatial positions between the graphics and the entities. This solution has been gradually phased out in practical applications because it cannot correspond accurately to the actual size of the graphics, failing to meet the requirements and standards for drawing. Therefore, users of AutoCAD who need to print the drawings they have created must master the knowledge in these areas. Below, using AutoCAD 2000 as an example, the solution is explained. In the actual process of mapping, depending on the size of the drawing area, the units used are generally meters or kilometers. When creating drawings, users usually work directly in AutoCAD using the data obtained from measurements. For example, a building that is 60 meters long and 20 meters wide is typically represented on the diagram as a rectangle with a length of 60 units and a width of 40 units. The user can then modify the diagram as needed, by adding elements such as fences, reference points, and vegetation surrounding the building. The addition of this information can be determined based on actual needs. After the user finishes drawing a picture, the next step is to render the graphic on the plotter. In this process, there is a corresponding relationship for the unit conversion between the user graphic and the result graphic. The print options in the AutoCAD system provide a function to carry out this conversion, but in practical use, many users do not understand what this conversion entails, so they are unable to make use of it effectively. Figure 1 shows the print scale setting sub-item under the printer settings in the AutoCAD system; this option can be used to resolve the issue mentioned earlier. The specific information contained in the graphic is as follows: the custom option allows the user to define the scale of the graphic themselves; in other words, the user can control the scale of the graphic on their own. By adjusting the corresponding values, the graphic can be displayed fully on the preview drawing, provided that it is possible to control the drawing scale. Figure 1: Setting of printing scale. The specific steps for customizing the scale are as follows: First, we must determine the ratio between the units measured and the drawing units used in the AutoCAD system. In the example above, 60m corresponding to 60 drawing units represents a relationship between them; it indicates that the entity is represented in the drawing system using 60 units of length. By the same logic, other attachments should also be represented in accordance with this corresponding relationship. With these settings, we have completed the computer representation of the entity. For the graphics that have been set up as described above, if they are printed directly on paper (such as A4 size, 297 mm × 210 mm), the resulting graphics generally do not meet our requirements, and this is mainly due to an incorrect printing scale being used. What is indicated in Figure 1 is that 1 drawing unit in the AutoCAD system corresponds to a length of 4 mm on the printed sheet; thus, the graphic can be represented on the sheet as a rectangle with a length of 240 and a width of 160. On the diagram we have created, 60 graphic units correspond to an actual length of 60 meters; therefore, 1 graphic unit corresponds to an actual length of 1000 mm (1 meter). This allows us to determine the relationship between the actual length of an object and the length of its representation on the diagram. In other words, 240 mm on the diagram (which is equivalent to 60 graphic units in AutoCAD) corresponds to an actual length of 60 meters. It is thus easy to conclude that the scale of the diagram we have drawn is 1:250. Then, we can make some necessary settings for the printing options, and adjust the graphics according to the scale requirements so that the printed output meets our needs.
My usual approach is: in the first step, I draw the diagram at an actual 1:1 scale; if a line is 1000mm long, I draw it as 1000mm long. After completing the drawing of the actual shape in the second step, enlarge the commonly used drawing frames (such as A4, 297mm×210mm) to a size that is just large enough to fit the previously drawn shape inside; the scaling factor for enlarging the frame corresponds to the scaling factor by which the original image is reduced. The same principle applies when the image frame is reduced. By doing this, when making annotations, there is no need to calculate based on proportions first; the values used for annotation are the actual dimensions of the drawing. It’s much more convenient! It’s for everyone to share; I’m not sure if everyone understands what I mean
Excuse me, on the second floor, should the scale factor on that drawing be filled in as 1:1 or something else?
It seems I still don’t understand; the multiple by which the image frame is reduced (or enlarged) is the same as the multiple by which the image is enlarged (or reduced). For example: there is a drawing created to scale, with an A4 frame measuring 297mm×210mm. In CAD, it is necessary to enlarge the frame by 10 times in order to accommodate the size of the original image; so you enlarge the A4 frame by 10 times and then place the original image inside it. When printing, use A4 paper; this way, the image you produce will be drawn at a 1:10 scale. And the annotations you make on the original image still represent the actual size values. If the drawing frame is not zoomed in or out, the scale of the drawing you create is 1:1; otherwise, it is not 1:1. This post was last edited by 921027abcd on 2008-2-23 12:10.]
Dude, why not use Tianhe CAD from Tsinghua University? Then these problems wouldn’t be an issue at all. TH PCCAD2007 (which supports CAD 2008) + TH PCCAD2006 + AutoCAD Mechanic 2006 – AutoCAD Mechanic 2006 is the mechanical version of CAD, along with CAD plugins developed by Tsinghua University. TH-PCCAD2006 is quite good. http://bbs.hcbbs.com/viewthread.php?tid=63733&page=1#pid594648 This post was last edited by chemsky on 2008-2-23 18:27]
And my usual approach is: the first step is the same as what was mentioned on the second floor. But after completing the second step of drawing according to the actual diagram, switch to layout printing; the paper scale can be adjusted using the commands on the viewport toolbar (or via the shortcut key Z). It might be a habit issue; I think doing it this way is also quite convenient! Share among everyone.
Can I do it the way mentioned on the 2nd floor as well?? I’ll give it a try
I also think that using a layout in paper space is indeed much more convenient
How is layout used? Could the original poster give a practical example to illustrate how it’s applied in practice?
The original poster didn’t intend to complicate simple issues, but that’s what they ended up doing. Where was LZ’s post copied from? What was said on the 2nd floor is correct; drawings should be made at a 1:1 scale, regardless of whether the ‘1’ represents meters, millimeters, or some other unit. This is a good practice. My approach: 1. First, determine the drawing scale: (1) Define the drawing area: for example, 50m x 40m, and decide on the unit of measurement: such as mm ； (2) Determine the dimensions of the drawings we need to produce (determined according to the regulations of different specialties, different contents, and different design institutes); for example, for banners, it is A1: 841x594 ； (3) Determine the scale: 50,000/841 = 59, and 400,000/594 = 67. Taking into account the need for margin space at the top, bottom, left, and right of the drawing frame, as well as the space required for the title bar, notes, material list, instructions, technical requirements, etc. (determined based on the type of drawing), the scale chosen is 1:100. 2. Modify the dimension style: In “Dimension Style – Adjust – Dimension Feature Scale”, change “Use Global Scale” to “100”. The text and arrows in the dimensions will use the system’s default value of 2.5 (or you can change it to the height you prefer); when the drawing is generated, both will be 2.5 mm in size. 3. Determine the text height: Since the drawing scale is 1:100, the font height should be calculated by multiplying the required height by 100. The font size of 5mm in the drawings should be 500 in height when drawing. 4. Drawing, annotation, and text: Scale the standard A1 frame by 100 times, and use it as a template (or draw directly within the 100-times-scale frame). 5. Printing: You can choose either “Scale according to drawing space” or “1 millimeter = 100 units” for the printing scale; there is little difference between them. Others: 1. Local zoom (reduce) view: Create a new dimension style and modify the scale factor in “Dimension Style – Primary Unit”. For a zoomed-in partial view by 3 times, set the scale factor to “1/3” (use fractions when it’s not possible to get a whole number, to ensure accurate lines and facilitate further zooming in and out) ； 2. The importance of drawing at a 1:1 scale: I often receive drawings from the equipment department; since they are not drawn to scale, various problems arise – the pipe openings of horizontal heat exchangers are located on the saddles, the pipe openings of suspended equipment collide with the floor slabs/beams, and the equipment can be depicted on the drawings but cannot be actually manufactured (hehe, due to insufficient space in reality)… Anger arises in my heart, and frustration sets in
Generally, before creating a diagram, a standard frame is first inserted and then enlarged to the desired scale. During the drawing process, the elements are drawn at their actual sizes, and the final output is printed using the size of the standard frame; the scale corresponds to the multiplication factor by which the frame was enlarged
Could you please explain it more clearly? Thank you!
To explain this clearly, it seems we’ll have to wait until someone creates a tutorial with both text and images! :lol
It’s been explained clearly enough. I wonder if there are anyone who works in electrical engineering drawing; the span can be drawn that way, but what about the utility poles? The tower height must be indicated inside the tower symbol!
Replying to floor 11: The explanation is quite detailed. However, regarding printing: it’s acceptable to use either \"Scale according to drawing space\" or \"1 millimeter = 100 units\"; there isn’t much difference between the two. I have some doubts about this – there is actually a difference. If \"1 millimeter = 100 units\" is chosen, the standard drawing frames often end up extending beyond the boundaries of the printed paper. For example, I chose ISOA1 and would like to ask experts for their insights on why
I want to take a look; I’ve been drawing a lot lately, and the template is no longer there
:Lol, usually it’s done as the guy on the first floor says.