If you have a block library that contains variations on an object or component and you insert them at various scales and rotations angles, you [...]]]>

I’ve written posts about how to create specific types of dynamic blocks and about some of their features, but I’ve never explained when and why you would use a dynamic block.

If you have a block library that contains variations on an object or component and you insert them at various scales and rotations angles, you can probably save a lot of time with dynamic blocks. For example, you may have a desk that comes in various lengths. You can create one dynamic block to replace all the individual variations.  Moreover, your dynamic block will give you even more flexibility to add additional lengths.

It takes some time to define a dynamic block — of course, simple ones take less time but complex ones can take a long time. For this reason, the most common use for dynamic blocks is to create a block library. That means you don’t usually define  dynamic blocks for your current drawing. Instead, you create them and save them to use in future drawings.

But if  you’ll need to draw several components in variations in your current drawing, you can create a quick dynamic block to save yourself some time.

The first part of the process of creating dynamic blocks is to define the block. Here’s an overview of the workflow:

1. In your block library drawing or a new drawing, create the block.
2. Choose Home tab> Block panel> Block Editor (BEDIT command) or just double-click the block. In the Edit Block Definition dialog box, choose the block, and click OK to open the Block Editor. (You can also start the BEDIT command, name the block, and create the objects in the Block Editor.)
3. Add parameters and associated actions, or geometric parametric constraints. Here’s a tutorial on creating a dynamic block.
4. Save the block definition in the Block Editor.
5. Close the Block Editor.
6. If the drawing will contain just this block, use the BASE command to set the drawing origin where you want the insertion point to be, usually somewhere on the block. You do this when creating a block library that has one block per drawing.
7. Save the drawing.

You may want to follow this process for any number of blocks. When your blocks are defined, do the following to insert your dynamic blocks:

1. In your current drawing, either use the INSERT command to insert the drawing containing the block, or use the DesignCenter to choose the block from within the drawing.
2. Select the block to see its special grips. These grips show you where you can modify the block.
3. Usually, you click and drag a grip to modify the block. Some dynamic block parameters involve choosing a visibility or option from a drop-down list or table.

Here you see the process of stretching the desk length.

When and why do you use dynamic blocks? What is your process for creating and storing them?

Sometimes, you want one action to execute a second action at the same time. If the relationship [...]]]>

Dynamic blocks, introduced in AutoCAD 2006, are very powerful, but sometimes they can get complicated. One of the more involved features of dynamic blocks is chaining. In this tip, I try to make chaining easy.

Sometimes, you want one action to execute a second action at the same time. If the relationship between the two actions is simple and direct, you can accomplish this easily — without chaining. You just attach two actions to the same grip on the same parameter. When you grip-edit one action, the other happens at the same time.

For example, in this desk set, the desk has a linear parameter and a stretch action attached to the right grip of the parameter. The top-right chair has a move action attached to the same grip. The bottom chair also has a move action attached to that same grip, but the distance multiplier is set to 0.5.

So when you stretch the desk, the top chair moves the same distance, always remaining lined up with the right side of the desk. The bottom chair moves half the distance, always remaining centered behind the desk.

But, your geometry may require more than one parameter.  To activate one action with another in this situation, you use the chaining feature. Note that the secondary parameter, the one whose action will be activated by the primary action, must be a point, linear, polar, XY, or rotation parameter. There are some other limitations, too, but they’re hard to explain, so just experiment.

Remember that you want one action (with its parameter) to activate another action, also with a parameter. So you need two actions and two parameters. Create a chained parameter as follows:

1. Create the block and open it in the Block Editor.
2. Decide on the parameters you’ll need and their actions.
3. Decide which action you’ll grip-edit in the drawing. This is the primary action that will activate the other, secondary, action.
4. Create both parameters first, before creating any actions.
5. Create the primary action and attach it to its parameter (the primary parameter).
6. When you specify the objects for the primary action, include the parameter of the secondary action. This is very important. But don’t include the objects that will be in the selection set of the secondary action.
7. Create the secondary action, attach it to its parameter, and select its objects.
8. Select the secondary parameter, open the Properties palette, and set its chaining property to Yes.

To summarize, the basic principles of chaining are as follows:

• The primary parameter has an action whose selection set includes the secondary parameter in addition to any other objects it will act on. (If the action is a stretch action, the stretch frame also needs to include the secondary parameter.)
• The secondary parameter’s chaining property is set to Yes.

Save your block, close the Block Editor and try out your chained dynamic block. When you grip-edit the primary action, the secondary action will be activated at the same time.

As you drag the primary parameter’s grip, the secondary parameter’s grip moves in response to the result of the primary action. For this reason, chaining is useful when you want to maintain a constant relationship between two components in a block.

In this cover, the handle needs to stay the same distance from the top of the cover. The cover comes in three sizes (the linear parameter has a value set) and has a stretch action. As the cover is scaled, the handle moves up.

Note: Once you’ve perfected your block, you can remove the grips from the secondary parameter, because you don’t need them. In the Block Editor, select the secondary parameter, right-click it, and choose Grip Display > 0.

The move action is attached to the top grip of its linear parameter. As the cover is scaled, this parameter (the secondary parameter) moves up, thereby moving the handle.

The book is only $10 and he’s offering a 40% discount [...]]]>

Edwin Prakoso has written an excellent and thorough e-book on AutoCAD blocks. In 69 pages, he covers the following:

• Creating, inserting, modifying, and replacing blocks
• Creating and using attributes
• Creating annotative blocks
• Creating dynamic blocks, including visibility states, parameters, and constraints
• Extracting data from blocks
• Best practices examples
• Managing and sharing blocks

The book is only $10 and he’s offering a 40% discount with the CN2010 code.  It’s only good until December 31st, which is why I wanted to get this post out to you now. That makes the book only $6!

I suggest that you take a look by clicking this link. (Full disclosure: I make 30% commission.) He also has 2 e-books on Revit, if you’re interested.

I asked Edwin some questions to learn more about him and why he chose this topic:

Q1: Why did you decide to focus on AutoCAD blocks?

I believe that to be productive in AutoCAD, we need to focus on three areas: having good templates, good libraries, and good customizations. Customization need programming knowledge, and not many people can create a program. But AutoCAD blocks are quite simple to create.

I have seen that AutoCAD blocks today can be really useful, not only as reusable content, but also to automate some tasks. By optimizing blocks, we not only become more productive, but also reduce human errors in our design.

Q2: Tell me a little about your background.

I worked in Architecture consultant for a couple of years, then I moved to a building contractor. So I’m familiar with the design process and how we use AutoCAD in that area. I saw that many people tried to create custom programs to be more productive. Then I started to work at an Autodesk reseller, so I had more chances to explore AutoCAD features. I started to see that much of the automation can be done in AutoCAD without any programming. One feature that we can use is AutoCAD blocks. For example, we can use dynamic blocks and data extraction.

Q3: You have 3 e-books, one on AutoCAD and two on Revit. Why did you decide to start writing? Are there any other books on AutoCAD in the pipeline?

I started to write on my blog since 2004. My first blog was written in Indonesian. Some of the readers asked if I could provide the contents in e-book format. It was not easy and expensive to have an Internet connection at that time. I thought it was a good idea. So I decided to also have e-books, especially for materials that can’t be covered in blog posts. At the moment I only have one AutoCAD e-book, but I have plan to cover more about AutoCAD best practices.
Wish me luck!

Good luck, Edwin!

This tutorial is updated for AutoCAD 2010 and 2011. Follow these steps:

When you insert a block, a Basepoint option appears with the [...]]]>

Blocks and basepoints go hand-in-hand. Knowing how to work with basepoints can make your life much easier. It’s so frustrating to insert a block and have it disappear into outer space because the basepoint is in the wrong location!

The Basepoint option of the INSERT command

When you insert a block, a Basepoint option appears with the Specify insertion point: prompt. When you use this option, you can move the insertion base point of the block to anywhere you want. This option can be really helpful sometimes but I don’t think it’s used very often.

The BASE command

A block library often has one block per drawing. You save each block in its own drawing. By default, the basepoint of a drawing is 0,0. But unless you put the block right at 0,0, you’ll want to change that. (Another option that works is to use WBLOCK and choose to write just the block. Then, the basepoint is taken from the block and is in the right place.)

Use the BASE command in the drawing containing the block to specify the origin of the drawing, which is usually on an object snap somewhere on the block. Then, when you insert the drawing, your basepoint will be right on the block.

The Basepoint parameter for dynamic blocks

Creating a Basepoint parameter

For a dynamic block, the Basepoint parameter  sets a base point for the block. This is useful when you’re turning a block into a dynamic block and want to change the basepoint. You add a Basepoint parameter in the Block Editor, from the Parameters tab of the Block Authoring Palettes, as you see here. The basepoint functions like any other block basepoint.

During insertion of a dynamic block, you can use the Basepoint option as I described earlier.

But you can do something else with dynamic blocks.

While you’re inserting a dynamic block, you can press Ctrl to cycle among the grips if their Cycling property is set to Yes. (By default, it is.) Each time you press Ctrl, the cursor moves to another grip on the block. This lets you visually see the results of each basepoint before you commit to inserting the block.

To check the Cycling property, double-click the block to open the Edit Block Definition dialog box, and click OK to open the Block Editor. Click any grip and open the Properties palette. Look for the Cycling property in the Misc section, as you see here.

Cycling property of dynamic blocks in AutoCAD

If the Cycling property is set to No, click the item, click the drop-down arrow, and choose Yes.

Do you have any other tips for controlling blocks with basepoints?

Thanks to Joel, whose comment to the earlier post helped [...]]]>

In a previous post, “Create a rectangle with a flexible corner,” I showed how to create a rectangle whose upper-right corner is strechable, creating a flexible rectangle that doesn’t lose its shape. In this post, I show how to do the same with a dynamic block.

Thanks to Joel, whose comment to the earlier post helped me figure this out.

I’ve covered aspects of this topic before. In “Tutorial: Display the area of an enclosed figure,” I show how to use fields to create a label that displays an area.

In “Tutorial: Create attributes,” I mention that you can use [...]]]>

You can use fields (AutoCAD 2005 and later) to create automatic labels that provide information about objects.

I’ve covered aspects of this topic before. In “Tutorial: Display the area of an enclosed figure,” I show how to use fields to create a label that displays an area.

In “Tutorial: Create attributes,” I mention that you can use fields in attributes.

In this tutorial, I’ll expand on the idea of using fields in attributes, which are labels attached to blocks. This example shows the use of fields that label geometric parameters of dynamic blocks.

1. Open the Block Editor. (Tools> Block Editor or Blocks & References tab> Block panel> Block Editor.
2. Create the objects for the block.
3. Create the parameter and action you want to label. For example, for a desk, I created a Linear Parameter and a Stretch Action. I renamed the Linear parameter’s label to Length in the Properties palette. If you need further instructions, you can download my complete dynamic blocks tutorial from my “Dynamic blocks tutorial” page.

1. Start the ATTDEF command (Draw> Block> Define Attributes or Blocks & Reference tab> Atrtributes panel> Define Attributes).
2. In the Attribute Definition dialog box, type in a tag name, such as Length. For the Deafult entry, type the text that you want to appear before the value, such as Length: . (Add a space after the colon.) Check the Constant check box so that you won’t get a prompt. The whole point is to make the label automatic. Set the Text Settings section as desired.
3. Then right-click in the Default text box or click the Insert Field button at the right to open the Field dialog box. From the Field Category drop-down list, choose Objects. Then choose BlockPlaceholder as the field name. The Block reference property should be the name of the parameter you used. This is Length in our example. Set the format as desired, and click OK.

Note: The Length property is on the list only because I created a parameter named Length. The other properties are available for all blocks.

1. You’re now back in the Attribute Definition dialog box, which should look like the figure below. Click OK. Place the label where you want it.

1. Save the dynamic block by clicking the Save button in the Block Editor. Close the Block Editor.
2. Back in your drawing, insert the block (Insert> Block or Blocks & References tab> Block panel> Insert). Before you specify the insertion point, you’ll see the following for the label.

After you insert the block, you’ll see the value of the field.

1. After you modify the dynamic block, you’ll need to update the field. In this example, changing the length makes the desk longer. Enter updatefield on the command line to update the field.

Tested in AutoCAD 2009.

Part 1: Dynamic Block Overview and Quick-Start Tutorial. In this white paper I explain the concepts behind dynamic blocks and suggest some scenarios for their use. I display [...]]]>

I’ve written three white papers for Autodesk on Dynamic Blocks. Together, these three white papers provide a thorough overview of the dynamic block feature.

Part 1: Dynamic Block Overview and Quick-Start Tutorial. In this white paper I explain the concepts behind dynamic blocks and suggest some scenarios for their use. I display some sample dynamic blocks and explain the steps for creating one. I define the components of dynamic blocks, parameters and actions. I end the paper with a short tutorial to run you through the process of creating, inserting, and editing your first dynamic block. Download Part 1(PDF, 10 pp.)

Part 2: Inventory of Block Editor, Commands, Parameters, Actions, and Parameter Sets. In this white paper I document dynamic block properties and characteristics. I list dynamic block capabilities and provide a thorough review of the Block Editor, which is the interface for creating dynamic blocks. Then I list and describe all the parameters, which are the building blocks of dynamic blocks. I explain how to attach actions to parameters. Actions are like editing commands, which control how you can edit a dynamic block. I end the paper with a table of parameter sets, which are parameter-action combos that you can quickly apply to a block. Download Part 2 (PDF, 12 pp.)

Part 3: Advanced Features of Dynamic Blocks. In the final white paper, I explain some of the advanced features, best practices, and capabilities of dynamic blocks. Here are the topics:

• Naming parameters and actions
• Selecting objects for actions
• Specifying stretch frames
• Cycling through insertions points
• Changing the direction of an action
• Keeping objects centered
• Stretching a block equally in opposite directions
• Chaining parameters
• Using visibility states
• Using lookup parameters and tables

Download Part 3 (PDF, 15 pp.)

Here’s a video showing the use of dynamic blocks.

Follow these steps to create a door that flips both ways:

Start with a door [...]]]>

You can create dynamic blocks that you can easily flip after you insert them. This is great for doors which may open from the left or right, or open inward or outward. Dynamic blocks were introduced in AutoCAD 2006.

Follow these steps to create a door that flips both ways:

Start with a door block, like this one. You might want to insert it into a new drawing. You don’t need to explode it; when you open it in the Block Editor, you’ll have access to all the individual components, as if you had exploded it. That’s one of the great features of dynamic blocks; you can work with complex blocks that contain many components and individually program each component.

Choose Block Editor from the Standard toolbar (the BEDIT command). Here’s what you see.

Note that the Block Editor has its own toolbar. It also has its own UCS icon. This is very important, because 0,0 in the Block Editor will be the insertion point of the block. When you open the block in the Block Editor, its insertion point will be at 0,0 in the Block Editor, like this:

The first flip action we’ll create will be like mirroring with a vertical mirror line; it will flip the door to the left or right. Unflipped, the door will be as you see it here, which means it opens from the right to the left. Flipped, the door will open from the left to the right.

Click the Parameters tab of the Block Authoriing Palettes window and choose Flip Parameter. At the Specify base point of reflection line or [Name/Label/Description/Palette]: prompt, choose the Label option. This option lets you customize the label. It’s important to change it, because we’ll have two flip parameters when we’re done. Enter Flip Left/Right.

You can also customize the names for both states (which appear in the Properties palette). so the next thing you see is this prompt:

Specify values for items in the flip property dropdown control:

Enter flip property value for an unflipped state <Not flipped>:

Enter flip property value for a flipped state <Flipped>:

You can leave the defaults (Not flipped and Flipped), but instead, enter Opens at right for the unflipped state and enter Opens at left for the flipped state. Later, when you select the block, you can see which state you have in the Properties palette.

You can change these values at any time by selecting the parameter and using the Properties palette.

Now the original prompt returns. Specify base point of reflection line or [Name/Label/Description/Palette]: Specify the midpoint of the bottom horizontal line of the door.
Specify endpoint of reflection line: Specify any point 90° above the midpoint, to make a vertical flipping line.
Specify label location: Place the label above the door.

Notice the exclamation point. That tells you that you haven’t completed the process of flipping the door. That’s because most parameters also require a corresponding action.

Click the Actions tab of the Block Authoring Palettes window and choose Flip Action. A Flip action always goes with a Flip parameter.

At the Select parameter: prompt, select the parameter you just added.

At the Select objects: prompt, select all the objects of the door. In this situation, you can include the parameter, too.

At the Specify action location: prompt, place the action, usually near the parameter label. It doesn’t show in your drawing, so it’s just for your convenience when editing the block in the Block Editor.

You can change the action’s name. Select it and change the Action Name value in the Property palette to Flip left/right action. I find it helpful to distinguish the parameter label from the action name. Our door now looks like this in the Block Editor.

Click Save Block Definition on the Editor’s toolbar (the 2nd button from the left). To try it out, click Close Block Editor. If you already have inserted an instance of the block in the drawing, you get a message about it. Click Yes.

To test the block, choose Insert Block from the Draw toolbar and choose the block. In the Insert dialog box, you should see that yellow lightning icon in the preview box, to show that it’s a dynamic block. Make sure that only the Insertion Point Specify On-Screen check box is checked and click OK.

Specify the insertion point in your drawing to insert the block. To flip it, select it and you’ll see the turquoise flip grip on the block. Click the grip to flip the door. Click it again to flip it back.

Watch the process in an AVI file.

When you’re satisfied, open the Block Editor again, choose the block and click OK. Now you need to add the flip for the other direction.

Again, click the Parameters tab and choose Flip Parameter. At the Specify base point of reflection line or [Name/Label/Description/Palette]: prompt, pick the midpoint of the right side of the door — the short side. You may have to zoom in to do this.
At the Specify endpoint of reflection line: prompt, move the cursor to the left and pick any point 180° from the first point (creating a horizontal mirror line).
At the Specify label location: prompt, pick a point to the right of the door, or perhaps just beneath it.

Tip: When you zoom in and out, sometimes the size of the labels gets out of synch. Click the Update Parameter and Action Text Size button on the Editor’s toolbar.

Select the parameter. In the Properties palette, change the label to Flip in/out.

Click the Actions tab and choose Flip Action. At the prompt, select the parameter you just created.

At the prompt to select objects, select the door. Not only can you select this action’s parameter, but you can select everything else (which makes it easy).

If you want, change the name of the action in the Properties palette. I changed it to Flip in/out action. Here’s the final dynamic block in the Block Editor.

Click Save Block Definition and click Close Block Editor. If you get the notice about an existing block reference existing in the drawing, click Yes.

Here you can see the block at work. It flips both ways!

Specifically, [...]]]>

Usually, I include the entire tip here, but this one is too long and includes a drawing. So instead, download the tutorial. This tutorial requires AutoCAD 2006 or later and will help you get up and running with dynamic blocks. You’ll learn how to add parameters and actions to make your blocks flexible and intelligent.

Specifically, you’ll work with a desk, chair, telephone, and computer block. You’ll create a block in which you can move the chair independently, stretch the desk within certain constraints, stretch the computer’s monitor from a drop-down list, and make the phone appear or disappear.

If you want to understand this powerful new feature, this tutorial is for you.

Here’s the final block in the Block Editor:

Here’s the same block in a drawing, reading for dynamic editing: