Sets the lineweight for the layer record object (DXF 370). This lineweight is used when the Lineweight property of an entity belonged to this layer is set to ByLayer value. The initial value is kLnWtByLwDefault by default. The same entity can be rendered using different lineweights in different viewports. 

The same layer can have different lineweights in different viewports. Therefore this method is overdriven. The method with one argument sets the own lineweight of the layer.

Example of Working with the Layer Record Object 

Specific Properties of Layers 

OdDbLayerTableRecord::lineWeight() method