4 ways to modify block definition

Block is very useful as reusable contents. And when you need to create similar objects in your drawing. One of the most popular benefit is when you need to modify all instances, you only need to modify one. All other instance will be automatically updated.

We will see four method that you can use to modify your block here.

Explode and recreate the block

This is the oldest way I know, the old school. The classic.

A long time ago, the only way to edit a block is by exploding the block to simpler object. Made any changes necessary, then recreate a block with the same name.

However, it’s not possible to recreate the block if you select the block name from drop down list.

You will see this warning if you select the block name from the list.

You need to type the exact block name in the block name field.

If you do it correctly, AutoCAD will ask you for confirmation to redefine the block like below. Select the Redefine block to confirm the changes.

Reinsert the block

Block usually is a reusable content. You create it to use it repeatedly. Because of this reason, you save the block in master file. Whenever you need it, you can simply insert it to your drawing.

If you need to modify the block, then you will want to modify it in master file. But how about the blocks in your drawing?

To update the block definitions in your drawing, you need to insert the updated block to your drawing again. AutoCAD will recognize that the block has the same name with existing block. It will ask you a question like below.

Choose redefine block, and your blocks will be updated.

Using block editor

Block editor is a very powerful tool to edit your block. Not only allow you to modify your block geometry, you can also create a dynamic block here.

You can activate block editor by double clicking a block OR select a block then right click> choose block editor from context menu.

You can also choose edit from AutoCAD ribbon, home tab> block panel.

One thing you must remember. When working with block editor, 0,0 is the insertion point. So don’t move the geometry unless you want to move the insertion point!

Edit block in-place

Edit block in-place is a great way to modify block when you want to use other objects in the drawing as reference. The tool we use is actually REFEDIT. It was originally for reference editing, but works for blocks too.

You can activate this by selecting a block, right click then choose edit block in-place from context menu. Or by using REFEDIT command.

This tool is not block editor. So don’t expect you will see specific block editing tools like in block editor.

Besides the ability to use other objects as reference, there is one more interesting about this method. You can add or remove objects to your block.

Use add or remove from working set from your ribbon.

Don’t forget to click save changes after you finish working with your block.

Which one is your preferred method?

So you have 3 methods to modify block. 4 if you are still using older version. Certainly, which one you use depends on the circumstances. But which one you preferred the most? Which one do you use often?

Or do you have other method that’s not mentioned here?

About Edwin Prakoso

I work as an Application Engineer in Jakarta, Indonesia. I've been using AutoCAD since R14 and Revit since Revit Building 9. I occasionally write for AUGIWorld magazine and also active in Autodesk discussion forum.
I'm an Autodesk Certified Professional (ACP) for Revit Architecture and AutoCAD. I'm also a member of Autodesk Expert Elite, appreciation for individuals who give contribution to Autodesk community.
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