Deleting blocks and renaming blocks

[Laurence]

Cadtutor could you tell me how I can remove a block . I have recently started to work with autocad 2002 Lt . and made a few blocks of furniture in a floor plan . I created them in a new layer (furniture) but realized they should have been drawn in the delpoints or 0 layer, then inserted into its new layer Is that correct and why? (the reason I'm asking is that one of the blocks acts strange in that when I pick it ,it disapears until place it with my cursor . The other issue is that I may want to redefine the name tag of the block . I have read your post on editing a block.
Thank you .

[CADTutor]

OK, this is a good topic for the Beginner's area.

Working with blocks and layers can be quite tricky until you appreciate some basic facts.

1. The individual objects in your block retain their original layer properties. However, when a block is inserted, it is inserted into the current layer. So, if you look at the layer properties of an inserted block, you will see the block layer properties and not the component object layer properties.

2. The layer "0" has some special properties with regards to blocks. If you create the component objects of your block on layer "0", they will take on the properties of the current layer when the block is inserted. This can be useful because it means that a single block definition can be given different layer properties such as colour etc.

3. Turning a layer off that has blocks inserted will not necessarily make the blocks invisible because the visibility of block objects is controlled by their native layers and not by the insert layer. EXCEPT that if you Freeze the insert layer, then the block will be invisible until the layer is Thawed.

4. You can Erase blocks just the same as any other object in a drawing. BUT, the block definition remains in the drawing databse, even if all blocks are erased. Again, this is a useful feature for creating drawing templates etc. However, you can permamently remove a block definition from a drawing using the PURGE command.

5. You can redefine an existing block definition simply by making a new block with the same name. AutoCAD will ask if you want to redefine the block. This is really useful if you need to make global changes that will affect many block insertions because all inserted blocks with that name will automatically be updated.

Of course, there are lots of other things to say, but the points above are the ones that should help new users the most. They're certainly the issues that seem to cause most confusion.

Hope this helps :)

Perhaps some of the others on the Forum can offer further advice.