Triangles

Triangle Square (Measuring Tool) Selection — Quick Reference

Triangle squares + speed squares + try squares — measuring + MARKING tools for AU workshop + carpentry + framing + metal fabrication. Set common angles (45° + 90° + 30° + 60°) quickly + precisely. Roofing rafter layout + saw guide.

Critical: Check SQUARE ACCURACY periodically — dropped squares lose precision. For precision metal work, use ENGINEER'S square (hardened + finer tolerance). PPE — see safety equipment. Brands: Sutton Tools, C.H. Hanson. Companion: measuring tools, combination squares, hand tools.

Engineering Triangles and Set Squares for Australian Workshop and Toolroom Layout

Triangles and set squares are the precision angle-marking tools used in toolroom layout, drafting, and workshop marking work. The fixed-angle geometry of standard triangles (30/60° and 45°) provides quick layout of the most common angles without the protractor reading and locking that adjustable angle tools require. For Australian toolmakers, fitters, and trade workers needing accurate angle layout, the right triangle set is essential. AIMS Industrial supplies engineering triangles in metal and plastic formats.

The triangle types we stock

• 30/60° set squares — fixed 30°, 60°, and 90° angles in one tool
• 45° set squares — fixed 45° and 90° angles
• Engineer's machined triangles — hardened steel triangles for precision layout work
• Combination triangles (matching set) — coordinated 30/60 and 45 triangles in matching sizes
• Adjustable set squares — clamped variable-angle triangles for non-standard angles
• Plastic drafting triangles — for general drafting and design layout

Where triangles earn their place

• Toolroom layout — marking 30°, 45°, 60°, and 90° angles on workpieces
• Engineering drafting — drawing accurate angles on engineering drawings
• Sheet metal marking — laying out fold lines and cut angles
• Joinery and cabinetwork — marking 45° mitre cuts and other standard angles
• Welding fit-up — verifying joint angles before welding
• Inspection and quality control — checking part angles against drawing requirements

Materials and accuracy

• Hardened steel — engineer's grade triangles for precision toolroom work; accurate to within minutes of arc
• Aluminium — lighter and corrosion-resistant; suit drafting and general workshop use
• Plastic (acrylic, polystyrene) — for drafting and design work where accuracy is the priority over durability

For workshop layout where the triangle is used as a straight-edge against rough surfaces, hardened steel earns its place. For drafting and design, plastic or aluminium triangles are fine.

Common triangle dimensions

Triangles are typically supplied in matched sizes — the longest side (hypotenuse for 45° triangles, longer leg for 30/60° triangles) determines the practical reach. Common sizes:

• 150mm — small, for detail work
• 200mm — general workshop use
• 300mm — standard drafting size
• 450mm — large drafting and layout work

Care and accuracy

Engineer's triangles are precision tools. Store flat or in a roll to prevent warping. Keep clean and lightly oiled to prevent rust on steel triangles. Inspect for visible damage at the corners — chipped corners give false-angle readings. For traceable inspection workplaces, periodic verification against a master angle gauge maintains accuracy.

Brands stocked at AIMS

Triangles are stocked from quality manufacturers covering both engineering precision and drafting use. For specific brand requirements, contact our team for current options.

Companion ranges at AIMS

Triangles sit alongside our broader measuring and layout range — see protractors, measuring tools, spring calipers and dividers, and radius gauges for the related products.

Need help speccing triangles for toolroom or layout work? contact our team — we'll match by application and accuracy requirement.

People Also Ask — Triangles

Q: What's the difference between a 30/60° set square and a 45° set square, and why would a workshop carry both?

A 30/60° set square gives fixed 30°, 60° and 90° angles in one tool, while a 45° set square gives fixed 45° and 90° angles. Carrying both covers the standard angle combinations used in toolroom layout and drafting without needing to reach for a protractor and lock in an angle for the common cases.

Q: When does an engineer's hardened steel triangle earn its cost over an aluminium or plastic one?

For workshop layout where the triangle is used as a straight-edge against rough surfaces, hardened steel earns its place — it holds accuracy to within minutes of arc under conditions that would mark up or distort a lighter triangle. For drafting and design work, plastic or aluminium triangles are fine, since accuracy against rough surfaces isn't the concern there.

Q: What sizes do engineering triangles typically come in, and how do I pick the right one?

Common sizes run 150mm (small, for detail work), 200mm (general workshop use), 300mm (standard drafting size) and 450mm (large drafting and layout work) — measured by the longest side, which determines the practical reach. Pick based on the scale of the layout or drafting work rather than defaulting to the largest option.

Q: How do I tell if a triangle has lost its accuracy over time?

Inspect for visible damage at the corners — chipped corners give false-angle readings, which is the main way these tools drift out of true. Store the triangle flat or in a roll to prevent warping, keep steel triangles clean and lightly oiled to prevent rust, and in traceable inspection workplaces, verify periodically against a master angle gauge.

Q: Beyond drafting, where do triangles actually get used in a workshop?

Toolroom layout for marking 30°, 45°, 60° and 90° angles on workpieces, sheet metal marking for fold lines and cut angles, joinery and cabinetwork for mitre cuts, welding fit-up for verifying joint angles before welding, and inspection and quality control for checking part angles against drawing requirements.