How to set width of vtkAxisActor2D?

I am using vtkLegendScaleActor as following:

    scaleActor = vtkSmartPointer<vtkLegendScaleActor>::New();
    scaleActor->RightAxisVisibilityOff();
    scaleActor->LeftAxisVisibilityOff();
    scaleActor->TopAxisVisibilityOff();
    scaleActor->LegendVisibilityOff();
    
    auto bottomAxis = scaleActor->GetBottomAxis();
    bottomAxis->SetWidth(0.3333);

I want the bottomAxis to be 1/3rd of the viewport width. Instead of the desired effect the Axis becomes extremely large. Going off of the screen as pictured below.

If I do not set width takes up .75 of the viewport and it looks fine but I need it to be smaller.