BricsCAD Lineweights: Screen Display vs Printed Thickness
BricsCAD lineweight on screen is a visual aid; printed thickness depends on object/layer properties, CTB/STB rules and plot options. A calibration sheet is the only reliable final check.
Beginner takeaway: Separate display lineweight from plotted lineweight, then test the actual PDF or paper output.
What you need to understand first
A line can look thick on screen but print thin, or the reverse. That does not necessarily mean the drawing is corrupt; display and output have different controls.
- BricsCAD supports object/layer lineweights and plot-style lineweight mappings.
- CTB/STB can modify the final plotted result.
- True-color and object properties can interact differently from indexed-color CTB assumptions.
Related guides: AutoCAD Lineweights & Plot Thickness Guide, How CTB Lineweight Mapping Works in AutoCAD, and PDF Lineweights Are Correct but Plotter Lineweights Are Wrong.
Step-by-step workflow
Step 1 — Identify property source
Where: Select object > Properties / Layer
Do this: Check whether lineweight is ByLayer, explicit or plot-style-driven.
Check: You know what should control thickness.
Step 2 — Check plot-style table
Where: PAGESETUP > CTB/STB
Do this: Inspect whether the style overrides lineweight.
Check: The mapping matches office intent.
Step 3 — Check plot options
Where: Print/Page Setup
Do this: Ensure lineweights/plot styles are included as required.
Check: Preview uses the intended rules.
Step 4 — Create calibration PDF
Where: Known test Layout
Do this: Plot several standard lineweights on final paper size.
Check: Relative thickness hierarchy is visible.
Step 5 — Check physical device
Where: Printer/plotter
Do this: Print the same PDF at Actual Size.
Check: Hardware does not distort the calibrated hierarchy.
What usually goes wrong
| What you see | Likely layer | First check |
|---|---|---|
| All lines same thickness | Plot-style/lineweight disabled | Check Page Setup options. |
| One color too heavy | CTB mapping | Inspect that indexed color. |
| True-color object ignores CTB expectation | Object/true-color behavior | Check explicit lineweight/style. |
| PDF right, paper wrong | Physical driver/device | Calibrate hardware separately. |
Practical example
A red object prints 0.50 mm while a true-color red-looking object prints 0.18 mm. If the project uses CTB, the indexed red may be mapped by color while the true-color object follows its own properties. Inspect the actual object data before editing the CTB.
What not to do
- Do not calibrate lineweights by monitor appearance.
- Do not change every object’s lineweight before checking CTB/STB.
- Do not blame the CTB when the PDF is correct and only one physical plotter differs.
Good office standard
Maintain a lineweight calibration Layout with the office’s normal CTB/STB and issue paper sizes. Reprint it after driver or plotter changes.
Quick verification before you move on
- Use one representative drawing or sheet, not a production batch.
- Verify page size, orientation and a known dimension.
- Compare Preview/PDF with the physical output when a printer is involved.
- Save the setting or set only after the result is repeatable.
Official references
Frequently asked questions
Does screen lineweight equal physical thickness?
No. Screen display is only a representation; verify PDF or paper output.
Can CTB override object lineweight?
Yes, depending on the plot-style mapping and object/color properties.
Why test on final paper size?
Perceived hierarchy and device rendering should be checked in the same output context used for production.
Explore more in BricsCAD Printing & Plotting Guide.