What are Blocks in AutoCAD, and Why Use them?
So far, we have learned how to utilize the Dimension in AutoCAD which is a part of three major tools to maximize the benefit of this great feature in our different architectural drawings;
In general, objects best suited to becoming part of a Block, are the most utilized within the drawing such as doors and windows, or symbols like a North Arrow and a section cutline. Therefore, to decrease the time spent each time drawing the same objects repeatedly, AutoCAD introduces two commands to facilitate these tasks: you will need to learn How to Make Blocks and Insert Blocks.
The term “Blocks” is used in AutoCAD to describe repeatable items that you place in your drawings as described before. Also, rarely called Symbols. So the terms “Blocks' Library”, and “Symbols' Library” basically, refer to the same thing in AutoCAD.
There are two main reasons why we use Blocks in our CAD drawings.
The first one is speed; Once we draw a block, we will never have to draw it again. We just have to select it and drop it into our drawing so we’re working faster making a kind of library for the most used elements in our drawings together.
The second reason is the file size; Using Blocks will greatly reduce the file size of your saved drawing, which in turn helps many of your drawings respond to the commands faster. It will also greatly reduce the file size of your saved drawing, which in turn helps many of the AutoCAD tasks go faster. Because AutoCAD, it’s all about working faster; and for this aim, it is an indispensable tool to use!
Notice | Disclaimer
- Your UI (User Interface) might slightly differ from the one shown in this tutorial depending on the AutoCAD version being used.
- Therefore it is highly advised to follow the global process as one whole knowledgeable entity (as it is) for educational purposes only.
- Actually, the AutoCAD © version used in this course is the 2013 edition.
- The site is not responsible for any data loss or harm of any kind, resulting from a bad usage of the commands and tools listed in this post. Therefore the information contained in this article is as it is, and is not to be modified under any condition.
Understanding the Blocks in AutoCAD
To create a Block, you can either enter B or select the Insert tab, and then from the Block Definition menu select the Create Block command. Note that we have optionally another type of block creation which is the Write Block that differs from the other one by its ability to create the block within an independent file not only within the current drawing.
All you have to do is to provide AutoCAD when prompted with the name of the file you want to save the block with, in addition to its location on your hard drive. When creating a Block Definition, we will need to define those three constants which are:
|The Block Definition dialog box, Photo Source: https://knowledge.autodesk.com/|
- The Block Name that you will choose to easily define your block from others.
- The Base Point helps you place the block in the drawing when inserting it.
- The Objects to select are to be grouped into the block. Here, we have three ways to choose from; you can either retain the selected objects in the drawing after being transformed into a block or instantly convert them into the estimated block, or even more, delete them from the drawing. The second choice is the most recommended.
Likely, we can scale the block if we want to always scale it with a specific scale factor, uniformly or not. The value of the Block unit in the Settings box is set according to the Units used in the drawing; Note that AutoCAD will do the scaling when the drawing unit is different than the one used in the block while inserting it into your drawing, so be aware!
Fill the Description box if needed; it is optional anyway. As a result, you will have your block stored in your current drawing, unless you will use the Write Block command instead (shorten by typing W).
Using Layer “0” with Blocks in AutoCAD
A note to say about using Layer 0 when creating a block. Actually, it is quite useful to draw the objects intended to define a Block with Layer 0; In fact, one of the basic characteristics of Layer 0 is its ability to change the Properties (i.e. the color and the line type) of any layer current while inserting it onto your drawing. Sort of like a Chameleon.
Therefore, the basic Rule for creating Blocks is to Create all your blocks on the Layer “0”.
Inserting Blocks Onto Your Drawing
To insert a block stored in your drawing, go to the Insert tab then from the Block menu click on the Insert button which will show the following dialog box.
|The Insert dialog box, Photo Source: Dummies.com|
We have the option of inserting blocks from two different sources: the current drawing and an external file location that you can select by clicking the Browse button next to the Name box list.
Pressing the Browse... button will lead you to a standard window that lets you choose your block file from your own hard drive or a specific working network. When you’ve selected a block name, a preview will be displayed on the side to facilitate the search. Just select the OK button, and the block will appear on your crosshairs depending on the pre-selected Basepoint defined when you first created the block and you can pick a point in the drawing where you want to insert it.
Blocks are one of the most important and powerful object types in AutoCAD and they are also very frequently used in almost all types of drawings. If you are not using blocks in your drawings yet then the time arrived when you should better start soon because you are missing some of the awesome benefits that AutoCAD offers.
What Are the Blocks and What They are Used For?
In the context of AutoCAD, Blocks are a set of geometries and objects that are grouped and act as a single object and they can be used in a drawing repetitively. The blocks which are used in the drawing are called block references and if you edit or modify one of them all its references with the same name will change automatically.
In addition, the BCOUNT (a LISP application integrated with AutoCAD) is capable of making a list of the available blocks and their quantity regarding their block names and more useful info. Also, you can export it to a spreadsheet editor such as Excel.
Blocks also help in keeping consistency in your project drawings; By using the same set of blocks you can avoid a lot of confusion among different members working on a project. This is the reason why many organizations prefer their own set of standard blocks which can be used and reused as per their own requirements.
On the other hand, you surely have heard about the Attributes which are special blocks with special and advanced features;
The Attributes are capable of storing any kind of data means of, Attributes will display some information such as manufacturer name, serial numbers, etc. which is associated with a block such as flooring tiles or other, and can be extracted to an Excel sheet file or a table drawing.
To create such blocks go to the Insert tab and then from the Block Definition menu click on the Define Attributes button which allows you to access the Attribute Definition dialog window as shown in the figure below:
|The Attribute Definition dialog window, Source: Dummies.com|
A number of parameters can be filled in here that control the way the final block will look, plus the type of information intended to be displayed in the block. In other words, we can refer to the Attribute as being a Label showing information for the related block object.
We can either show the type of tiles used on the floor or the wood code for the doors, etc. and every piece of information can be displayed as a referential code to facilitate the task of preparing the BOQ documents and other needed reports.
Blocks v/s Groups
GROUPS have a little similarity to Blocks as they can also be used in some ways where you want to make a singular entity from multiple shapes and geometries. Unfortunately, Groups don’t have the same flexibility that Blocks have, but if you want to categorize multiple objects as a single unit then Groups are the best option for you.
How to Create Dynamic Blocks?
🛈 It is also useful to read: Dynamic Blocks CAD: A Time-Saving Tip for Productivity
Creating Dynamic Blocks is similar in many ways to the normal Blocks but with some actions that we can add to the block definition that allow us to perform various tasks associated with it such as flipping the block vertically or horizontally, stretching it, etc...
For instance, we will draw a detailed door as shown below which we will convert to a block definition by following the process described earlier in this post. Having the block created, we can now access the Block Editor by right-clicking on it and then selecting the Block Editor from the right-click menu as shown in the figure below:
|Accessing the Block Editor from the right-click menu, Photo: 101ArchiTechProjectsAndBlogs Archive|
Or alternatively, we can just double-click it to launch the Editor. Next, we will choose the Flip Parameter from the Parameters tab on the Block Authoring Palettes.
AutoCAD will prompt you to specify the base point of the Reflection Line, which is just the midpoint between the basepoint and the endpoint of the arc, and any point selected in the vertical direction starting from the previously specified point and forwarded up. (see the figure below for more clarification)
|In the Block Editor, choose the Flip parameter from the Parameter Tab, Photo: 101ArchiTechProjectsAndBlogs Archive|
Next, the Flip parameter will be created and named Flip state1, as shown above. Do not forget to select your desired basepoint location for future insertion; To do so in the Dynamic Block creation, select the Basepoint parameter while having the previous Block Authoring Palettes palette active and running.
The following step will be adding the related action to your block; Click on the Actions tab on the same previously opened palette and select the Flip action this time. (see Fig. below) Next, you will be prompted to select the parameter you want to apply the action for.
|Choosing the Flip Action from the Actions Tab, Photo: 101ArchiTechProjectsAndBlogs Archive|
Therefore, select all the objects that form the intended block including the Flip state1 parameter, and then hit the Enter ↩ button. (Objects should be highlighted to ensure their selection) You can optionally test your block before closing the Editor by starting the Test Block command found in the Open/Save menu. Now close and exit the Block Editor tab.
Likewise, you can use other actions associated with the related parameter such as the Stretch action for the windows blocks that need to be modified regarding the variation of the size of their openings to fit inside.
Using the DesignCenter Palette for blocks
AutoCAD came with a small integrated library of some standard blocks that you can use in your various drawings. This library of blocks, normally located in the installation folder of the AutoCAD files or alternatively in the Program Files folder, can be accessed from the DesignCenter palette. To open it you can use either the keyboard shortcut CTRL + 2 or you can use its command ADCENTER.
You can search for a folder named DesignCenter on your hard drive as well.
The design center is simply a palette just like properties or layer properties manager palette on which you can click on the home icon → select the en-us folder → DesignCenter folder → and then select the drawing file from which you want to extract the blocks.
Note that you can access other features than the blocks such as layers names, linetypes, or textstyles included within the file.
For example, you can use the kitchens.dwg file for kitchen blocks or the House Designer.dwg for common household blocks. After selecting the file select Blocks from the object type and now you get a collection of blocks from which you can insert the predefined blocks in your drawing by a simple drag and drop.
|The House Designer.dwg file showing the available blocks that you can insert in your various drawings in the DesignCenter palette, Photo: 101ArchiTechProjectsAndBlogs Archive|
You can also use the DesignCenter to extract blocks from an existing drawing. Simply click on the open icon on the top left of the design center then locate your drawing and process it in the DesignCenter palette.
Now navigate to the drawing and select blocks and you will have your complete list of blocks from the drawing in the palette. You can drag and drop these blocks to bring them to your current drawing as described above.
Using Tool Palettes for Blocks
You can access the tool palette by using its keyboard shortcut CTRL + 3 or its related command TOOLPALETTES.
The tool palette has many common blocks (especially dynamic blocks) that you can use directly in your drawing simply by dragging and dropping them in your drawing. You can also create your own tool palette and place your favorite CAD blocks on it, or you can create an entire catalog of your standard CAD blocks using tool palettes.
As it was said before there are plenty of customizable tools that you can adjust according to your needs and priority which makes AutoCAD the ultimate software for all!