Layiso and the blocks

Hello. I am cleaning up my dwg from some unwanted layers. I select one layer draw an object and layiso it to see what do I have in this layer, but it shows only that object I drew. So I guess some blocks are using this layer. Am I right or there is another explanation? How can I see which blocks are using this layer, please?

A few scenarios to investigate:

Have you tried a purge? It's always possible that the layer is empty (you can't purge or delete the current layer, so double check for that).

If the block's inserted on that layer, but doesn't contain any geometry on either Layer0 or that layer it would behave in the way you describe.

Can you see the blocks *before* you do the LayIso? If the layer the blocks are on is frozen and the blocks contain geometry on the layer you're trying to isolate it would behave like that.

It's possible that an un-used block is on that layer.

Do any of your dimension styles reference that layer, or do blocks within your dimension styles (you can set the arrows to be any block)?

dJE

Thanks for quick response. I purged the drawing while that layer wasn't active, but it still remains. So I think it this layer is used in one of the blocks. Is there a way to check in which blocks this layer is used? As you said it's possible that an un-used block is on that layer, but after I purge my dwg shouldn't the un-used block be deleted? Also I didn't get what do you mean by "do any of your dimstyles reference that layer"?

There are several reasons a layer cannot be purged or deleted. AFAIK, an unused block would not prevent it from being purged and dimensions styles do not reference layers.

A couple not already mentioned are empty text entities or zero length geometry.

There are several threads here discussing various reasons for not being able to delete a layer but a good thing to start with is WBlocking your entire drawing. Or, if you want to track down what is on that layer, use QSelect.

Thanks for advice, Qselect helped to find that some doors where under that layer, however after I changed the layer of that doors and wanted to delete that obsolete layer by purging it, it didn't work. I have one question: I have a door as a block under layer "Doors", but the elements inside that block are under layer "Wood", so if I want to delete layer "Wood" from my drawing but I don't know that my doors using the layer "Wood" how do I delete it? Qselect won't select it, right? (because it is inside the block)

....AFAIK, an unused block would not prevent it from being purged....

Disagree.... if the layer is referenced by a block definition (even if the block is unused) the layer can not be purged.

I have one question: I have a door as a block under layer "Doors", but the elements inside that block are under layer "Wood", so if I want to delete layer "Wood" from my drawing but I don't know that my doors using the layer "Wood" how do I delete it? Qselect won't select it, right? (because it is inside the block)

You could use QSELECT to isolate all the blocks in the drawing and EXPLODE them. Use QSELECT again to find those objects that are using the layer you wish to purge. Once you've found the objects, UNDO to put the blocks back together. The problem with this method is that you'll have to identify the block by it's geometry, not its block name will not exist because it's been exploded.

Alternately, you could change the color of "Wood" layer to something that will make it easy to identify the blocks that contain objects on that layer.

This was a good advice. I selected all my blocks, pasted them into another dwg and exploded. They contained those layers, but I could not find those layers. After I purged the dwg, those layers where gone. So in my original file I still have those layers, and I think that they will not affect my drawing since they are 0 geometry. It seems that those layers where somehow related to some blocks but where not used..

If you're SURE there's nothing of value on that layer.... LAYDEL will get rid of it (and any object(s) on that layer.

or

use LAYMERG to merge the layer you don't want into another (similar) existing layer

Post the if you like.... perhaps someone can identify exactly what's referencing the layer.

Yes I will probably laydel them. How can I post my dwg right here?

Use the "Go Advanced" button to the lower right of the reply window, then upload the drawing using "Manage Attachments" (there is a filesize limitation... 1MB I believe)

Disagree.... if the layer is referenced by a block definition (even if the block is unused) the layer can not be purged.

You're right but I was thinking that you would probably be purging the block at the same time.