Lesson 8 : Symbols (Blocks)

Symbols

Add ready-made symbols or your designs into your AutoCAD drawings.

In AutoCAD, symbols and details that you insert into a drawing are called blocks. A block is a group of shapes (lines, circles, text, etc.) that are combined into one single object with a name.

Here are a few examples of blocks you might see, in different sizes and uses:

4 Key Parts of a Block

1. Block Definition This is the “blueprint” of the block. It’s saved in a drawing file or template. You can create it yourself or import it.
2. Block Reference This is the actual block that appears in your drawing. It’s based on the block definition.
3. Base Point When you insert a block, this is the point where your cursor grabs it. You can move or rotate the block using this base point.
   
4. Block Insertion Tools You can insert blocks using several tools:
   • The block gallery on the ribbon
   • The Blocks palette
   • The Tool Palettes window
   • Autodesk DesignCenter

Why Use Blocks?

Imagine you have a chair block. Instead of drawing 12 chairs separately:

• You insert the same block 12 times
• It’s faster and easier to move, copy, and rotate
• You can add extra info (like part number or vendor) to each block
• If you change the block definition, all 12 chairs update automatically
• It saves space in your file, which is important for big projects

Note: In everyday talk, “block” can mean either a block definition, a block reference, or both.

Insert Blocks into a Drawing

You can insert blocks from several places:

1. Another drawing file You can insert a complete drawing (like a detail view) as a block. These are often kept in folders called block libraries.
   
2. Drawing files that contain only blocks For example, a drawing that contains just different types of trees. You insert only the tree you need. These are called block library drawings.
   
3. Blocks created in your current drawing If you’ve drawn a set of items (like a cubicle layout) that repeats, you can turn them into a single block for reuse.

After inserting a block, you can move, copy, rotate, or scale it like any other object.

Use the Blocks Palette

To use the Blocks palette:

1. Go to the Home tab, click Insert, then Blocks from Libraries (This opens the BLOCKSPALETTE)
   
2. The first time you use this, a file dialog opens to choose your block library
3. Click Browse to find a folder of sample blocks (like HVAC symbols)
   
4. Choose a file (e.g., an HVAC drawing), then click Open
   
   
5. Click on the block you want, and place it in your drawing

Now that block is copied into your drawing and is ready to reuse. Use Browse again if you want to switch to a different file.

Tip: You can change the block preview settings and experiment with other options at the bottom of the palette.

Other Helpful Tabs in the Blocks Palette

• Current Drawing: Shows blocks in the drawing you’re working on now
• Recent: Shows blocks you used recently (from any file)
• Favorites: You can right-click a block and add it here for quick access

Create a Drawing to Use as a Block

Sometimes, you create a separate drawing file just to use it as a block later.

Note: You can save these files in cloud storage (like Google Drive or OneDrive) to use them on different computers.

When you make a block drawing, place an object at 0,0—this becomes its base point when inserting.

This method is often used for:

• Standard detail views
• Title blocks
• Drawing borders

Tip: Create folders for your blocks and organize them. You can even add those folders to your Places bar in the Open/Save dialog for easy access.

Manage Blocks in a Drawing (Optional)

There are ways to manage block definitions inside your current drawing.

• Use PURGE to remove blocks that are no longer used—this reduces file size
• Use BLOCK to create new block definitions directly in your drawing
• Use EXPLODE to break a block into its individual parts
• Then, use BLOCK again to create a new version, or WBLOCK to save it as a new file

Tip: Blocks can include attributes—text data like part number, vendor, or cost. You can export this data into a table or file. Some blocks are dynamic—they can change shape depending on settings or where they are placed.

Summary & Best Practices

Here are some good ways to use and organize your blocks:

• Create one drawing file per block, and group similar blocks in folders
• Use block library drawings that contain several blocks related to a theme
• Add important blocks (like title blocks) directly into your template files
• Choose the block tool that works best for you: palette, ribbon gallery, tool palettes, or DesignCenter
• Store your blocks in the cloud for easy access across different devices
• Use blocks from trusted commercial websites when available, but double-check that they are to scale and correctly drawn