Mechanical drafting is the translation of an engineer’s or designer’s concept into detailed, dimensioned technical drawings that manufacturers, fabricators, and machinists can work from. It’s the critical step between design and production — and in Australia, mechanical drawings must meet specific standards before they can be issued for fabrication, used in a council submission, or signed off by an engineer.
This guide covers what mechanical drafting services include, which Australian Standards apply, how much they cost in 2026, and what to look for when engaging a provider. See our full mechanical drafting services for what Optimal Drafting offers.
What Is Mechanical Drafting?
Mechanical drafting covers all CAD documentation for mechanical engineering — from individual machined components through to complex assemblies of hundreds of parts. The primary output is dimensioned 2D drawings in DWG or PDF format, though mechanical drafters also produce 3D models in SolidWorks, Autodesk Inventor, or CATIA as the basis for those drawings.
A complete mechanical drawing package typically includes general arrangement drawings (GAs), individual part/detail drawings, assembly drawings with bill of materials (BOM), and installation or maintenance drawings. For manufactured products, this set is the definitive reference for production, quality inspection, and spare parts management.
Types of Mechanical Drafting Services
Fabrication and Shop Drawings
Fabrication drawings are produced for manufacturing — giving the fabricator every dimension, tolerance, material, finish, and weld specification needed to produce the part or assembly correctly first time. Key elements include:
- Orthographic views (front, side, top) in third-angle projection per AS 1100.201
- All dimensions with correct tolerancing per AS/NZS ISO 286 (limits and fits) or AS/NZS ISO 1101 (GD&T)
- Material specification, heat treatment, and surface finish callouts
- Weld symbols to AS 2812 and AWS A2.4
- Thread callouts (metric per AS 1722, UNF/UNC where required)
- Title block with part number, revision, scale, drawing standard, and approval
Assembly Drawings
Assembly drawings show how individual parts fit together — typically a cross-sectional or exploded view with balloon callouts referencing a bill of materials (BOM). The BOM lists every part by item number, part number, description, material, quantity, and supplier or make/buy status. Assembly drawings are essential for production, quality inspection, and after-sales support.
GD&T (Geometric Dimensioning and Tolerancing)
GD&T is the preferred tolerancing system for precision mechanical parts — it communicates form, orientation, location, and runout tolerances using standardised symbols, rather than numeric ± tolerances which are ambiguous for complex geometric features. Australian mechanical drawings follow AS/NZS ISO 1101 for GD&T symbols and AS/NZS ISO 5459 for datum reference frames. Our mechanical drafters are proficient in full GD&T tolerancing for precision machined components.
Piping and P&ID Drawings
Mechanical drafting also covers process plant documentation — piping isometrics, general arrangement (GA) drawings for pipework, and process and instrumentation diagrams (P&IDs). P&IDs show all process equipment, control valves, instrumentation, and piping connections, and are the primary reference document for plant operations and maintenance. Our mechanical drafting team produces P&IDs to AS 1101.6 and ISO 10628.
3D Modelling for Manufacturing
Many clients provide 3D models in SolidWorks, Inventor, CATIA, or Fusion 360 and need 2D drawings extracted and annotated to Australian Standards. Others need a 3D model created from scratch — from concept sketches, existing paper drawings, or a physical part (reverse engineering via 3D scanning). The 3D model then becomes the master from which 2D fabrication drawings are derived. For more on 3D work, see our BIM and 3D modelling services.
Australian Standards for Mechanical Drawings
| Standard | Application |
|---|---|
| AS 1100.201 | Mechanical engineering drawing — projection, dimensioning, surface texture, tolerancing |
| AS/NZS ISO 1101 | GD&T — geometric tolerances for form, orientation, location, runout |
| AS/NZS ISO 286 | Limits and fits — tolerances for cylindrical and plain features |
| AS/NZS ISO 5459 | Datum reference frames for GD&T |
| AS 1722 series | Metric screw threads — designation and tolerancing |
| AS 2812 | Weld symbols — welding, brazing, and allied processes |
| AS/NZS 3992 | Pressure equipment — weld requirements for pressure vessels and piping |
| AS 1101.6 / ISO 10628 | P&ID graphical symbols for process plant |
| AS 4024 | Safety of machinery — relevant for mechanical guarding drawings |
Mechanical Drafting Costs in Australia (2026)
| Service | Typical Cost |
|---|---|
| Simple part drawing (1–2 views, basic dims) | $80–$200 per sheet |
| Complex machined part (GD&T, tight tolerances) | $200–$500 per sheet |
| Assembly drawing with BOM | $300–$800 |
| Full fabrication drawing set (5–10 sheets) | $1,500–$4,000 |
| P&ID (single system) | $500–$1,500 |
| 3D model creation from scratch (simple part) | $300–$800 |
| 3D model creation (complex assembly) | $1,500–$5,000+ |
| Hourly rate (mechanical drafter) | $70–$130/hr |
| Dedicated drafter (weekly, staff leasing) | $1,200–$2,500/week |
Industries We Serve
- Mining and resources — conveyor components, structural platforms, pipe spools, material handling equipment, shut-down documentation packages
- Manufacturing — production tooling, jigs and fixtures, machine design, equipment modification drawings
- Oil and gas — pressure vessel drawings to AS 1210, piping isometrics, P&IDs for process plant
- Defence — military specification (MILSPEC) compliant drawings, revision control to ISO 9001
- Food and beverage — stainless steel fabrication drawings, hygienic design documentation
- HVAC and building services — ductwork fabrication drawings, mechanical equipment shop drawings
How to Evaluate a Mechanical Drafting Provider
- Check their projection standard — Australian mechanical drawings use third-angle projection (AS 1100.201). First-angle (common in Europe) looks similar but places views differently. An error here means the drawing is misread by local fabricators.
- Ask about GD&T competence — many offshore providers apply ± tolerances where GD&T is required. If your parts need tight geometric control, verify the drafter understands datums, feature control frames, and material condition modifiers.
- Confirm software and native file delivery — SolidWorks SLDPRT, Inventor IPT, or STEP along with DWG and PDF. Never accept a drawing set without the underlying CAD files; you’ll need them for future revisions.
- Verify revision control practice — a professional drawing set has a defined revision history in the title block, with each change documented. Drawings without proper revision control become liabilities on long-running projects.
Frequently Asked Questions
What is the difference between a fabrication drawing and an engineering drawing?
In practice they’re often the same document. “Fabrication drawing” emphasises that the drawing is for manufacturing use — it carries all the information the fabricator needs (dimensions, tolerances, materials, welds, finishes). “Engineering drawing” is the broader category that includes all technical drawings used in engineering, including assembly drawings, schematic drawings, and installation drawings, not just fabrication-specific ones.
Can you produce drawings from a physical sample when no CAD files exist?
Yes. We can measure a physical part using callipers and coordinate measurement tools, create a 3D CAD model, and produce a fully dimensioned fabrication drawing from it. For complex or large parts, 3D scanning is more efficient — the scan data feeds directly into the CAD model. This is a common request for legacy machinery components, wear parts, and imported equipment where the OEM no longer supports the part.
Do your mechanical drawings comply with AS 1100.201?
Yes. All Optimal Drafting mechanical drawings use third-angle projection, correct line types and weights per AS 1100.201, metric dimensions (mm unless stated), and standard title blocks with part number, revision, material, scale, and approval fields. For projects with specific client drawing standards, we adopt those instead — we’ll request your drawing standards template at project kickoff.
How do you handle drawing revisions on long-running projects?
We maintain a revision register for all drawing sets. Each revision is documented in the title block (revision letter, description, date, approved by) and a revision history table is kept on the drawing. For projects with frequent revisions, we can set up a shared folder system or integrate with your document control platform (Aconex, BIM 360, Procore) for issue management.
Ready to start your mechanical drafting project? Contact Optimal Drafting for a free, no-obligation quote — we respond within one business day.
📞 1800 287 223 | 📧 info@optimaldrafting.com.au