Continuing our Deep Dive look into AutoCAD – focusing on blocks – let’s take a look at editing blocks. [This is #5 so far in the series, if you are just joining us start here to see the other articles]

AutoCAD has three primary methods of editing a block after it is created: Exploding & Redefining, Editing In Place, and the Block Editor. Each has its pros, cons, and place to use. One of the great things of using blocks is that by editing the block definition (the recipe of what the block is) all instances within the drawing will update automatically.

On the chopping block - by WendyOn the chopping block” featured image courtesy of Flickr

Exploding & Redefining

Think of this as the wily old veteran who’s been on the team forever, maybe has lost a step, isn’t as fancy as the new boys on the team, but when it comes down to crunch time knows how to get the job done. Exploding the block back to its original entities and then redefining the block once the desired changes has been made is the first method of modifying blocks. It was, for a long time, the only way of modifying blocks.

PRO: Can be the quickest way to made a copy of a block definition

CON: You need to make sure you select the correct rotation, scale, and insertion point of the modified geometry otherwise it will negatively adjust existing blocks


  1. Use the EXPLODE command to explode one of the block instances into its original elements (aka lines, arcs, circles, etc)
  2. Make modifications or add new geometry using existing AutoCAD commands
  3. Use the BLOCK command to redefine the block by picking (or entering) the exact name as the existing block definition

Edit In Place

Think of this as your typical user, competent and been around long enough to know what’s going on. With Edit in Place you can modify the block contents without exploding. Its like opening up the block, temporarily disabling all other objects in the drawing, and working with the geometry contained within the block.You can add geometry, remove geometry, and you can also add existing geometry from within the drawing to the block or copy out geometry from the block into the drawing. You can modify and add attributes. You can also work with blocks within a block (nested)

PRO: Modify blocks without the need to explode. Can copy in or out geometry from the drawing or into the drawing. Provides a mechanism to select a block nested within another

CON: Does NOT work with Dynamic Blocks. No method to create a copy of a block definition


  1. Select the Block (so its grips appear), right-click, from the menu select Edit Block In-place
  2. In the Reference Edit dialog use the reference tree to select the level of block you want to modify. If there are no nested blocks then just click OK to proceed
  3. All other objects in the drawing will become ghosted (and locked). Make the necessary changes to the block
  4. The Edit References panel will be available in every tab of the Ribbon. Use this to either Save Changes or Discard Changes.

Block Editor

Although its been around for a number of years the Block Editor is still the new kid on the block when it comes to modifying blocks. Although intended for the creation and modification of Dynamic Blocks you can also use this environment to not only modify existing blocks but to create new block definitions.

PRO: Only environment for working with Dynamic Blocks. Block geometry is loaded into the editor making it clear what you are working on. Save As option to make a copy of the Block Definition.

CON: No method to copy in geometry from the drawing into the block or from the block into the drawing


  1. Select the Block (so its grips appear), right-click, from the menu select Block Editor. Alternatively from the Insert tab start the Block Editor (Block Definition panel) and select the desired block from the list
  2. Make the desired changes
  3. Save Block and Close the Block Editor


So you just edited your block, added an attribute and everything looks good. But when you save your changes and exit the block editor, the attribute does not appear, nor can you edit it. To further confuse the issue, if you insert a new instance of the block the attribute appears in all its glory! So what happened?

Take a look at a previous post Dude, Where’s My Attribute?