A technical drawing is not simply a picture of an object — it is a precise, standardised document that communicates exact form, dimensions, tolerances, and materials to engineers, manufacturers, and contractors. In the UK, technical drawings follow the BS 8888 standard (Technical Product Documentation), which defines how drawings should be structured, how dimensions should be applied, and what symbols and notations mean. AutoCAD 2026 provides all the tools you need to produce drawings that meet these standards and hold up to professional scrutiny. This guide takes you through the process from drawing setup to final output.
Understanding Drawing Standards: BS 8888
BS 8888 is the UK standard governing technical product documentation, aligned with ISO GPS (Geometrical Product Specifications). Key principles you must follow include:
- First-angle projection — the UK convention for orthographic projections. In first-angle projection, the front view is placed at the upper left, the view from the right is placed at the upper right, and the plan view is placed below. This contrasts with third-angle projection used in the United States.
- Dimension lines — dimensions use thin continuous lines with arrowheads, terminating at projection lines that extend slightly beyond the dimension line. Dimensions are placed above the dimension line, reading from left or bottom.
- Line types — visible outlines use thick continuous lines; hidden lines use thin dashed lines; centrelines use thin chain lines; dimension and projection lines use thin continuous lines.
- Title block information — every drawing must include the part name, drawing number, revision, scale, material, surface finish, tolerances, the drafter’s name, and the date.
AutoCAD’s linetype library includes all the standard line types required: CONTINUOUS (visible outlines), HIDDEN (dashed hidden lines), CENTER (chain lines for centrelines), and PHANTOM (long-short-short for section cutting planes).
Setting Up Your Drawing Template
Before producing any technical drawing, establish a template that automates standard settings. A professional technical drawing template should contain:
- Units: Set to Millimetres with 0.0 decimal precision for most engineering work, or 0.000 for precision machined parts.
- Layers: Create layers for outlines (thick continuous), hidden lines (thin dashed), centrelines (thin chain), dimensions, annotations, and the title block. Assign lineweights: 0.5mm for outlines, 0.25mm for all other lines.
- Text styles: Use an ISO-standard font such as ISO Proportional or a simple sans-serif like Arial. Text height should be proportional to the drawing scale — typically 3.5mm at drawing scale on an A3 sheet.
- Dimension styles: Set up a dimension style that uses first-angle projection conventions. Configure arrow type to Closed Filled, set text height to match your annotation style, enable precision to 0.0mm, and enable tolerance display if required.
- Title block layout: Set up an A3 or A1 layout tab with the correct title block as a block reference.
Creating Orthographic Views
A complete technical drawing typically shows multiple views of the same part to fully define its geometry. In first-angle projection, the standard views are:
- Front elevation (principal view) — the most informative view of the part, showing its characteristic shape.
- Plan view — placed directly below the front elevation.
- Side elevation — placed to the right of the front elevation (for the left-hand side view), or to the left (for the right-hand side view).
In model space, draw all views at full scale (1:1). Use construction lines (XLINE) to project points horizontally and vertically between views — this is the key technique for ensuring all views stay correctly aligned. A horizontal XLINE projected from the top of the front view should define the top of the side elevation; a vertical XLINE projected from the right edge of the front view helps position the side elevation.
Use the OFFSET command to establish overall dimensions and internal features. Apply TRIM and EXTEND to clean up intersections. Place hidden lines on the HIDDEN layer, ensuring AutoCAD applies the correct dashed linetype automatically.
Centrelines and Symmetry
Every circular hole, cylindrical feature, and symmetrical element requires a centreline. Draw centrelines on a dedicated CENTERLINE layer using the CENTER linetype. Centrelines should extend slightly beyond the feature outline — typically 3–5mm at drawing scale.
For circles, add both a horizontal and vertical centreline passing through the centre point. For a series of bolt holes on a pitch circle diameter (PCD), add a circle on the centreline layer representing the PCD, plus individual cross centrelines for each hole position.
Use AutoCAD’s CENTERMARK and CENTERLINE annotation commands (available in the Annotate tab, Centerlines panel) to automatically generate associative centrelines that update if the geometry is moved or scaled.
Applying Dimensions Correctly
Dimensioning is where many AutoCAD users make critical errors. Follow these rules:
- Never dimension over or through part geometry — dimension lines and projection lines belong outside the part outline.
- Chain dimensions with care — a long string of toleranced chain dimensions accumulates error. Where overall accuracy matters, use baseline dimensioning (all dimensions originate from a single datum surface).
- Dimension every feature once — do not repeat dimensions in multiple views.
- Use DIMLINEAR for straight features, DIMRADIUS for radii (labelled R), DIMDIAMETER for diameters (labelled ∅), and DIMANGULAR for angles.
- Add geometric tolerances using the TOLERANCE command — this inserts feature control frames that specify flatness, straightness, cylindricity, true position, and other geometric tolerances per BS 8888.
Sections and Detail Views
When internal features cannot be shown clearly by hidden lines, use a section view. Draw the cutting plane line on the front or plan view using the PHANTOM linetype, labelled with letters (e.g., A-A). Draw the section view showing the cross-section at that cut plane, apply hatching to cut surfaces (use the ANSI31 hatch pattern for steel, or ANSI37 for aluminium), and label the view accordingly.
For small features requiring more detail than the main scale allows, create a detail view: draw a circle around the area of interest, label it (e.g., Detail B), then reproduce that area at a larger scale (e.g., 2:1 or 5:1) elsewhere on the sheet.
Finalising and Plotting Your Drawing
Switch to your Layout tab to set up the final drawing sheet. Create viewports at the required scale, freeze layers you do not want visible in each viewport (such as construction lines), and complete the title block attributes.
Before plotting, run a final check: are all features dimensioned? Are tolerances specified where required? Is the projection angle symbol (a first-angle projection symbol — a truncated cone drawing) included in the title block? Are all views labelled consistently?
Plot to PDF at a resolution of at least 600 DPI to preserve drawing quality for digital submission and archive.
Produce Drawings That Communicate Precisely
Technical drawing is a discipline where precision is non-negotiable. AutoCAD 2026 provides the tools to produce drawings that fully conform to BS 8888, communicate unambiguously, and support professional engineering and manufacturing workflows.
AutoCAD 2026 is available from GetRenewedTech for £39.99 — everything you need to produce engineering drawings to the highest professional standard, at a price accessible to individuals and small teams alike.
