When a dimension line weight is ByBlock, what determines the weight

[lamb]

In the Dimension Style Manager, the line weight (for example) is by default 'ByBlock'. It is not obvious to me what controls that line weight, since it is not obvious what 'block' is being referred to. Is it possible to change that value, or do you need to choose 'ByLayer' or select a particular weight?

[pendean]

BYBLOCK means your layer settings would control everything unless there is manual override created by the user in PROPERTIES command. Exactly the same concept applies to BLOCKs, where the naming convention come from originally.

[lamb]

But there is no identifiable BLOCK whose properties you can set ...

[pendean]

You are over-thinking it: it's like someone getting upset the name APPLE has no reference to the fruit's color like ORANGE has for example.

BYBLOCK setting gives you the user the ultimate control to manually override an object's settings independent of the layer settings. If you use BYLAYER that extra control is removed. You the user get to decide which you prefer to employ and use in your own files.

HTH

[lamb]

It's not that clear. The default line weight is ByBlock, and there is some value, but I see no way to change that value. I can choose something other than ByBlock to change it (ByLayer, or a specific value), but I don't see a way of changing it if it is ByBlock.

[cwr-pae]

The dimension itself is the block in this context, indicating an individual control per object.

Select the dimension and type properties (or preopen the properties window with ctl+3 then select). In the upper part of the properties window (named General) find the line weight row, select the down arrow list and pick a line weight to apply to all parts of the dimension that are set to by block in the style.

Or under the lines and arrow area, pick the part (dim line or ext line) to apply a line weight to and overriding line weights set elsewhere. 

[Anonymous]

@Anonymous,
Really good explanation. Thank you. I learned something.
Dave

[lamb]

Yes, I understand all that. But why is the default ByBlock rather than a value? There seem to be inconsistencies that are confusing. Create a new drawing using acad.dwt. Draw a line in model space. In paper space, dimension the line. The Dimension Style Manager claims that the dimension line style and line weight are ByBlock. But look at the properties of the dimension as drawn. It says that line width and line style are ByLayer. If you change the layer style or width then the dimension does indeed follow that.

You can then change the properties to ByBlock and the line style and line width are no longer dependent on the layer properties, but there is nothing that I can see to say where the new values come from or what they are. By inspection, the line style is Continuous, but I don't know what the line width is ...

I suspect that this is some vestige of a former paradigm that makes no sense any more and we just have to ignore it and hope it will go away 😉 

[ВeekeeCZ · Accepted solution]

1) dimension IS a block.

2) byblock means inherit setting from a superior entity

3) if the is no superior entity, it's using the default setting 7/continuous/default (0.25 if not changed by LWDEFAULT sysvar or by LINEWEIGTH command).

But why is the default ByBlock rather than a value?  

Because only that way it acts like it's not a block.

[lamb]

Thanks! This is a great, clear explanation that makes sense to me.