Lineweights determine how thick or thin entities appear on the screen and / or when printed.

The lineweight can be set ByLayer, ByBlock, Default or to a specific value.

Lineweights are defined in millimeters or inches, depending on the LWUNITS system variable.

You cannot assign lineweights to planes, points, TrueType fonts, and raster images.

The options to set the lineweight are:

  • ByLayer: The lineweight is determined by the Lineweight property of the current layer. Changing the Lineweight property of a layer will affect all entities that have their lineweight set ByLayer on this layer.
  • ByBlock: Entities created using the lineweight ByBlock, are get the Default lineweight until they are included in a block definition. The entities then inherit the lineweight of the block when you insert the block into a drawing.
  • Default: The default lineweight is saved through the LWDEFAULT system variable. Changing the Default lineweight affects all the entities in the entire drawing that have the lineweight set to Default.

System variables

The CELWEIGHT system variable defines the lineweight for new entities.

The LWDEFAULT system variable sets the value of the Default lineweight.

The LWDISPLAY system variable controls the display of lineweights. Click the LWT field in the Status bar to toggle the lineweight display On/Off.

The LWDISPLAYSCALE system variable controls the display scale of lineweights in the Model tab. Values between 0 and 1 are accepted.

Printing lineweights

Entities using an index color will use lineweights when printed only if the Color Table (CTB) or Plot Style (STB) is defined as Use object lineweight. Otherwise the lineweight is defined by the entity color or plot style.

Entities using a true color always use the object line weight when printed.