AutoCAD® 2009 For Dummies®

Chapter 17. The ABCs of Blocks

In This Chapter

• Introducing blocks

• Creating block definitions

• Inserting blocks

• Using attributes in blocks

• Removing unwanted block definitions

Chapter 11 shows you how to copy objects within a drawing or even to another drawing. That's one way to use AutoCAD to improve drafting efficiency. You can copy a DWG file and then modify it to create a similar drawing — an even better productivity booster, as long as you're in the habit of making similar drawings. But all those are baby steps compared to the techniques that I cover in this chapter and the next: treating drawings, parts of drawings, drawings saved in Web format (DWF, or Design Web Format), and raster images as reusable and updateable modules. If you want to make drafting production more efficient with AutoCAD, you want to know how to use blocks, xrefs, DWFs, and raster files.

A block is a collection of objects grouped together to form a single object. You can insert this collection more than once in the same drawing, and when you do, all instances of the block remain identical. By redefining the block definition, you can automatically change all instances of the block insertion at once. Although a block lives within a specific drawing, you can transfer copies of it into other drawings. And you can add fill-in-the-blank text fields, called attributes, to blocks.

Before AutoCAD 2008, block attribute values were limited to a single line of variable text with a maximum of 255 characters. You can now create ...