Bylayer VS. Byblock Colors

[Anonymous]

So I've been using AutoCAD for a long time now, started out on ver. 10 way back when but this is a question that I'm really not sure how to answer.

I've been creating a PowerPoint presentation listing/showing basic operations in AutoCAD.

One involves the basics of creating blocks.

I was taught to always use bylayer for my line colors and to always place those items on layer "0".

I've had some push back from a few people telling me that I should be telling people to use byblock instead.

Since this will allow nested blocks to change color too.

Well I have always been under the impression that this something else you should never do, nest a block.

Well I really am not sure how to answer these requests since it has just always been my practice.

I do not remember being given a specific reason not to do it the other way.

So I was hoping that I could get some input on the pro's and con's of these practices so that maybe I can arrive at a fair answer when approaching these subjects in the future?

Thank you for any input.

Radar

[Anonymous]

If the objects inside the block are BYLAYER, they will be the color/linetype/line weight of the layer the block is inserted on.

If the objects inside the block are BYBLOCK, they will be the color/linetype/line weight that the individual block insertion is assigned to.

For instance, when the objects are BYLAYER, if the user wanted to assign a different color to the block, they would not be able to. They would have to change the color of the layer.

If the objects are BYBLOCK, the block can be assigned a color independently of the layer color.

My preference is BYBLOCK because it offers the user more flexibility. If there is a standard where block x must always be a certain color/linetype/lineweight, regardless of any unique circumstances, then BYLAYER would be more appropriate.

[Anonymous]

Quote from Samthearcher,

"For instance, when the objects are BYLAYER, if the user wanted to assign a different color to the block, they would not be able to. They would have to change the color of the layer."

In my world; plant system layout; I would say that you are trying to tell me something specific by changing the color of that item.

I would then tell you that you should use an extention on a standard layer to signify that message.

The new layer would use a specific color that tells me that item is new, being relocated or maybe it's being modified.

By using the extention on the layer name, that allows me to use filters to seperate those layers making it easier to control them through the layer manager.

[dgorsman]

As you noted using BYBLOCK has some advantages ie. you don't want a user changing the color of an instance; if it should be a different color it should be on a different layer.  Helps enforce standard practices if objects should be on an appropriate layer.

Nesting blocks has its uses.  For example, I have a large tracked crane model which is a single block, containing two bogey blocks, each of those contain multiple track pad blocks.  I have some detailed valve blocks which use solids for certain body parts and blocks for repetitive elements like bolt heads.