Line Weight Guide — Apps

Element	Weight	Notes
Cut walls / Structure Cut walls/structure	0.50 mm	Thickest line. Cut walls in section
Cut elements Cut elements	0.35 mm	Cut columns, slabs, stairs
Outlines / Elevation Outlines/elevation	0.25 mm	Visible outlines, elevation contours
Furniture / Detail Detail/furniture	0.18 mm	Furniture, fixtures, finish details
Dimensions / Text Dims/text	0.13 mm	Dimensions, annotations, reference lines
Hatch / Pattern Hatch/pattern	0.09 mm	Thinnest line. Material hatch

Type	Usage	Description
Continuous	Visible edges, outlines	Solid line — Visible edges
Dashed	Hidden edges, elements above	Dashed — hidden edges, elements above
Center (Chain)	Center lines, axes of symmetry	Chain — center lines, axes of symmetry
Phantom	Future work, adjacent parts	Phantom — future work, adjacent parts
Section cut	Section cut line	Section cut — cutting plane location
Property line	Site / property boundary	Property/site boundary

AutoCAD Color	CTB Weight	Common Layer	Usage
Red (1)	0.50 mm	A-WALL	Walls (cut)
Yellow (2)	0.35 mm	A-COLS	Columns, structure
Green (3)	0.25 mm	A-DOOR, A-GLAZ	Doors, windows
Cyan (4)	0.18 mm	A-FURN	Furniture, fixtures
Blue (5)	0.13 mm	A-ANNO-DIMS	Dimensions, text
Magenta (6)	0.09 mm	A-PATT	Hatch, pattern
White (7)	0.25 mm	0 (Default)	Default layer
Gray (8)	0.09 mm	A-GRID	Grid, reference lines

💡 CORE PRINCIPLE

Line weights must be adjusted for scale and paper size. Weights that look good at 1:50 on A1 will be too thick at 1:200 on A3.
Use the tables below as reference when creating CTB files.

RECOMMENDED CTB — DETAIL SCALE (1:5 ~ 1:20)

Element	1:5 (A3)	1:10 (A3)	1:20 (A3)	Notes
Cut Structure Cut walls/structure	0.70	0.60	0.50	Thickest line
Cut elements Cut elements	0.50	0.40	0.35	Cut columns, slabs
Outlines / Elevation Outlines / Elevation	0.35	0.30	0.25	Visible edges
Furniture / Detail Detail/furniture	0.25	0.20	0.18	Finishes, fixtures
Dimensions / Text Dims/text	0.18	0.15	0.13	Dimension lines, annotations
Hatch Hatch/pattern	0.13	0.10	0.09	Material representation

RECOMMENDED CTB — PLAN / SECTION (1:50 ~ 1:100)

Element	1:50 A1	1:50 A3	1:100 A1	1:100 A3
Cut Structure	0.60	0.50	0.50	0.40
Cut elements	0.40	0.35	0.35	0.30
Outlines / Elevation	0.30	0.25	0.25	0.20
Furniture / Fixtures	0.20	0.18	0.18	0.13
Dimensions / Text	0.15	0.13	0.13	0.10
Hatch / Grid	0.10	0.09	0.09	0.07

RECOMMENDED CTB — SITE PLAN (1:200 ~ 1:500)

Element	1:200 A1	1:200 A3	1:500 A1	1:500 A3
Building Outline	0.40	0.35	0.35	0.25
Property Line	0.30	0.25	0.25	0.20
Roads / Paths	0.25	0.20	0.20	0.15
Landscape / Context	0.15	0.13	0.13	0.10
Dimensions / Labels	0.13	0.10	0.10	0.07
Contour / Hatch	0.09	0.07	0.07	0.05

QUICK FORMULA

Base formula: A3 weight × 1.2~1.4 = A1 weight
Scale conversion: Larger scale (1:50) = thicker, smaller scale (1:200) = thinner
Minimum printable weight: Laser 0.05mm / Inkjet 0.07mm / Plotter 0.09mm
Most important: Cut vs non-cut line weight difference ≥ 2×for the drawing to be readable

1. MODEL SPACE vs LAYOUT

Model Space — Always draw in real dimensions (1:1)
Layout (Paper Space) — Set paper size and scale here
Beginner mistake: Drawing to scale in Model Space ❌

2. VIEWPORT SCALE SETUP

Layout tab → double-click Viewport → select scale in status bar
1:100 = set 1xp to 0.01
Lock Viewport: select VP → Properties → Display Locked = Yes
Always lock! Otherwise accidental zoom breaks the scale

3. SHOWING LINE WEIGHTS

If line weights are not visible on screen:
Status bar → click LWT button (enable)
Or LWDISPLAY → 1 (Enter)
Display is for reference only. Actual output is controlled by CTB

4. CTB vs STB

CTB (Color Table) — Assigns plot weight by color. Most common in Korea
STB (Style Table) — Assigns plot style per object. Common in Europe/US firms
Schools typically use CTB. Layer color = plot weight
Red → 0.50mm, Yellow → 0.35mm, Green → 0.25mm ...

5. TEXT HEIGHT vs SCALE

For 3mm text height when printed:
Model Space text height = print height × scale
1:100 → 3mm × 100 = 300mm in Model Space
1:50 → 3mm × 50 = 150mm in Model Space
Annotative feature auto-adjusts (recommended)

6. DIMSCALE

When dimensions appear too small or large:
DIMSCALE = scale number (100 for 1:100)
Or use Annotative dimensions (recommended)
Dimensioning in Layout ignores DIMSCALE

Line Weight & Type Guide