Summary of CAD commands and CAD shortcut key features related to CAD dimensioning

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To complete graphic annotations quickly and accurately in the HaoChen CAD software, it is first necessary to draw with precision, secondly to set up CAD annotation styles appropriately, and finally to be familiar with the CAD commands, shortcuts, and features related to annotations. Below, taking Haochen CAD as an example, we will introduce the CAD commands related to dimensioning, CAD shortcuts, and some features. I. Commands and shortcuts related to dimensioning: HaoChen CAD provides more than twenty commands related to dimensioning. The commonly used ones include linear dimensioning, aligned dimensioning, radius dimensioning, angle dimensioning, and leader dimensioning. The standard way to use these commands is by accessing them through the command panel or menu toolbar. Many people use the shortcut keys for annotation commands directly in order to improve operational efficiency. Below, I will introduce the commonly used commands that are marked, along with their shortcut keys. If you’re interested, you can memorize the shortcut keys; it’s enough to remember just the ones you use most often. Dimension style: Opens the Dimension Style dialog box to create or modify dimension styles; command name: DIMSTYLE, shortcut key: D. Linear dimensioning: Creates horizontal or vertical length dimensions; command name: DIMLINEAR, shortcut key: DLI. Alignment dimensioning: Creates length dimensions parallel to the direction of the graphic; command name: DIMALIGNED, shortcut key: DAL. Arc length annotation: Used to indicate the length of an arc; command name: DIMARC, shortcut key: DAR. Coordinate labeling: The X or Y coordinate value of the labeled point; command name: DIMORDINATE, shortcut key: DOR. Radius dimensioning: Used to dimension the radius of a circle or arc; command name: DIMRADIUS, shortcut key: DRA. Diameter dimensioning: Used to dimension the diameter of a circle or arc. Command name: DIMDIAMETER, shortcut key: DDI. Angle annotation: Used to indicate the angle between two lines; command name: DIMANGULAR, shortcut key: DAN. Bent dimensioning: Used to indicate larger radius values in a bent format; command name: DIMJOGGED, shortcut key: DJO. Center mark: Marks the position of the center; command name: DIMCENTER, shortcut key DCE. Baseline marking: Select a reference standard; use the side corresponding to this standard as the starting point to sequentially mark the dimensions before selection. Command name: DIMBASELINE, shortcut key DBA. Continuous dimensioning: Select a base dimension to continuously dimension the distances between adjacent selected points. Command name: DIMCONTINUE, shortcut key: DCO. Form and position tolerances: Specify the shape and position tolerances of a machine part; command name: TOLERANCE, shortcut key: TOL. Quick Leader: Creates leaders and related annotations; it is the leader format used in earlier versions. Command name: QLEADER, shortcut key: LE. Multiple leads: A new type of lead format that allows for the setting of multiple lead styles, as well as the merging and alignment of leads. Command name: MLEADER, shortcut key MLA. Quick dimensioning: It is possible to select multiple graphic objects and directly apply dimensions to them in terms of continuity, baseline, radius, or diameter. It is also possible to select multiple dimensions and change their format, for example, changing continuous dimensions to baseline dimensions; the command name is QDIM. How to label multiple dimensions at once? Have you used the Quick Dimensioning (QDIM) feature? Edit Annotation: It is possible to modify the text content of an annotation or set its rotation and inclination angles. The options for this command have been split into several separate commands in the menu, such as Incline and Align Text. Command name: DIMEDIT, shortcut key DED. Edit annotation text: Text of annotations or other text that can be edited; command name: DDEDIT, shortcut key: ED. In higher versions of CAD, this command can be activated by double-clicking on the dimension text. Dimension override: Replace system variables related to dimensions by specifying the name and value of the variable to be replaced, and then select the dimension to make the changes. This requires a good understanding of the system variables related to dimensions. Command name: DIMOVERRIDE; shortcut key: DOV. Dimension inspection: Add and remove inspection information associated with dimensions; command name: DIMINSPECT. Dimension spacing: Adjusts the spacing between linear dimensions and angular dimensions; command name: DIMSPACE. Unlink annotations: Makes associated annotations no longer linked to the graphic. Command name: DIMDISASSOCIATE, shortcut DDA. Emphasize association: Re-associate the dimension with the graphic; command name: DIMREASSOCIATE. II. What is annotation association, and how is it controlled? In HaoChen CAD, when the graphics are adjusted after annotations are added, the annotations update automatically. This is because there is a relational connection between the annotations and the graphics; this is what is known as annotation linkage. But to associate a label with a shape, you must capture a point on the shape when adding the label, or select the object directly. For example, when capturing the two endpoints of a line or directly selecting a line for annotation, as you drag the intersection points of the line to change its length, the annotation will automatically adjust accordingly. In addition, when annotating graphics in the layout space viewport, if annotations are made by selecting objects or capture points, annotation linking can ensure that the values in the paper space match those in the model space, which is also convenient for designers who frequently use layouts and perform dimensioning there. It is possible to control whether to indicate an association using a variable; the variable is dimassoc. By entering this variable name in the command line and pressing Enter, one can view the current value set, and it can also be reset to a new value. dimassoc has three values: 0, 1, and 2. The functions of these values are as follows: when set to 0, the newly created annotations are scattered. If you find that the annotation is not a single entity after making the markings, you should consider that the value of dimassoc might be set to 0; when it is set to 1, the annotation forms a single entity but is not associated with anything else. When set to 2, the annotation is associated. Note: When annotating graphics within a viewport in the paper space of a layout, to establish a relationship, you must use snap or object selection for annotation; otherwise, no such relationship can be created. Furthermore, if after making annotations in paper space, you double-click on a viewport to go into model space and adjust the graphics, the annotations should update accordingly. In the case of scaling the view, which means changing the scale of the viewport, the annotations in paper space will not update automatically; however, the association between them remains, and if you adjust the graphics at that time, the annotations will be updated. It’s also simple to figure out the role of this variable. Draw a few simple shapes on an empty drawing, set dimassoc to 0, 1, and 2 respectively, then label them in both model space and layout space. Drag the grip points of the shapes to change their sizes under different conditions, and observe the effects in various scenarios. In addition to control through variables, HaoChen CAD also provides commands for disassociating and reassociating, allowing us to selectively handle the association of individual dimensions. III. Why is an exclamation mark displayed? Many people have encountered this problem, with a bunch of exclamation marks appearing in the annotations, as shown in the figure below. If the annotation is not set to be associated, or if no associated graphic or geometric feature points are selected when creating the annotation, then the annotation remains in an unassociated state. Even for associated annotations, if we move the annotation separately or delete the graphic associated with it, it will become a non-associated annotation. In HaoChen CAD, after opening the annotation monitor, an icon consisting of a yellow color with an exclamation mark appears first on the unassociated dimensions in the drawing. Now that we know the reason, it’s very simple to prevent exclamation marks from appearing in the image. There are two options: one is to turn off the annotation monitor directly, and the other is to re-associate the annotations. This CAD tutorial focuses on the shortcut keys for CAD commands related to CAD dimensioning in HaoChen CAD software. All of these commands share one important feature: they are interrelated, and it is hoped that this will help everyone complete drawing dimensioning more effectively and quickly. In fact, it’s not difficult to master these functions and features; what’s more challenging is figuring out how to set various proportions and parameters in the annotation styles.