Design Guidelines

Design parts that
manufacture first time

File requirements, tolerances, and design rules for every process we offer. Follow these and your parts will match your model — guaranteed.

What to upload

DXF / DWG

2D Cutting & Bending

Preferred for laser cutting, waterjet, and CNC bending. Export one layer per feature type.

  • AutoCAD 2000 or newer
  • 1:1 scale in millimetres
  • Closed polylines only
  • No dimensions or text layers
  • Separate layers for cut, etch, fold
STEP / STP

3D CNC Machining

Required for all CNC machining jobs. Includes full 3D geometry, holes, and pockets.

  • STEP AP203 or AP214
  • All features modelled — no implied geometry
  • Material callout in filename or notes
  • Critical tolerances noted in drawing or email
  • Include inspection drawing as PDF
PDF

Reference Drawings

For general reference only. Always supply a DXF or STEP as the primary file — we cannot quote from PDF alone.

  • Use for tolerance callouts
  • Thread specifications
  • Finish and surface treatment notes
  • Assembly instructions
  • GD&T callouts

Standard process tolerances

ProcessStandard ToleranceMin FeatureMax Sheet / PartNotes
Laser Cutting±0.1 mm0.8 mm hole dia1,500 × 3,000 mmKerf ~0.2mm, accounted in quote
Waterjet Cutting±0.15 mm1.5 mm hole dia2,000 × 4,000 mmNo HAZ; ideal for hardened steel
CNC Machining (3-axis)±0.025 mm0.5 mm end mill500 × 400 × 300 mmTighter tolerances available — quote individually
CNC Bending±0.5° angleBend radius = 1× thickness3,200 mm bend lengthAllow bend deduction in flat pattern
Powder Coating60–100 μm1,800 × 900 mmMask critical surfaces in DXF
Anodizing (Type II)7–10 μm900 × 600 mmAccount for build-up on bore fits
Anodizing (Type III)25–50 μm600 × 400 mmHardcoat — tight bores need pre-machining

Rules by process

Minimum Hole Diameter

Holes must be at least equal to the material thickness in diameter. Smaller features may not cut cleanly and risk tab-out.

Min: 1× material thickness
↔️

Edge-to-Edge Spacing

Keep at least 2mm between any cut feature and the part edge, and 3mm between adjacent cutouts, to prevent distortion.

Min: 2mm from edge · 3mm between cuts
📏

Minimum Bridge Width

Thin material bridges between features must be at least 2× the material thickness to survive cutting without warping.

Min: 2× material thickness
📝

Text & Engraving

Minimum text height is 5mm for engraving; 3mm for full cutout lettering in fonts with open counters (avoid closed counters at small sizes).

Min engraving height: 5mm
🔗

Tabs for Small Parts

Parts under 50mm in any dimension are automatically tabbed in production. We break tabs and clean edges before shipping.

Auto-tabbed under 50mm
🌀

Corner Radii

Interior corners can be perfectly sharp. Exterior corners can be sharp or radiused — your choice. Avoid acute interior angles under 15°.

No restriction on exterior corners
💡 Tip: Set all geometry to a single colour on one layer, with no dimensions, hatch, or text. Clean DXFs quote faster and manufacture without issues.

Minimum Hole Diameter

We can machine holes from 0.5mm diameter. Specify depth-to-diameter ratio — avoid blind holes deeper than 6× diameter.

Min: 0.5mm dia · Max depth 6×D
📦

Inside Corner Radii

All milled inside pockets have a minimum corner radius equal to the end-mill radius used. Design pockets with r ≥ 1mm unless a sharp corner is essential.

Min inside radius: 1mm
🔩

Threads

Specify thread standard, size, and depth in your drawing. We machine M2–M24 metric threads and custom inch threads. Minimum thread engagement: 1.5× diameter.

M2–M24 standard range
📐

Wall Thickness

Minimum wall thickness 0.5mm for aluminium, 0.8mm for steel. Thin walls cause chatter and deflection — consult us for designs under 1mm.

Min wall: 0.5mm Al · 0.8mm steel
🌀

Undercuts

3-axis machining cannot reach undercuts. Design parts to avoid undercuts, or contact us for 4-axis quoting on parts that require them.

Undercuts require 4-axis — quote individually
🔬

Tolerances

Default tolerance is ±0.025mm. Tighter tolerances (±0.005mm) are available at a premium — annotate these in your drawing and mention at order time.

Default ±0.025mm · Tight ±0.005mm
💡 Tip: Include a PDF drawing with your STEP file, especially for parts with tight tolerances, threads, or surface finish requirements. It removes ambiguity and ensures your parts are right first time.
📐

Minimum Flange Length

The minimum bent flange must be at least 3× the material thickness to allow the press brake to grip without marking the part surface.

Min flange: 3× material thickness
🔄

Bend Radius

Standard inside bend radius is 1× material thickness. Tighter radii cause cracking on high-tensile materials. Use our K-factor table for flat-pattern calculations.

Standard: 1× thickness inside radius

Hole-to-Bend Distance

Keep holes and slots at least (2× thickness + bend radius) away from any bend line to prevent distortion during bending.

Min: 2T + R from bend line
↕️

Relief Cuts

Add relief cuts at the end of each bend line where it meets another edge. Minimum relief width = material thickness, depth ≥ bend radius.

Relief: width = T · depth ≥ R
💡 Tip: Provide the flat-pattern DXF with bend lines on a separate layer. Our engineers check your K-factor before bending — we'll flag any issues before cutting.

Minimum Hole Diameter

Minimum hole diameter is 1.5mm due to the garnet jet kerf width. For holes near minimum size, account for slight taper with very thick material.

Min: 1.5mm hole diameter
📏

Kerf Width

Waterjet kerf is approximately 0.8–1.2mm depending on material. Our pricing engine adds kerf compensation automatically.

Kerf: ~0.8–1.2mm (auto-compensated)
📐

Taper

All waterjet cuts have a slight taper angle (0.1–1°) on the cut face, increasing with material thickness. Specify "taper down" or "taper up" for precision fits.

Taper: 0.1–1° increasing with thickness
🧱

Max Thickness

We cut up to 150mm in mild steel, 100mm in aluminium, and 80mm in stainless steel. Harder materials reduce max thickness.

Max: 150mm MS · 100mm Al · 80mm SS
💡 Tip: Waterjet is ideal for materials that can't be laser cut — glass, stone, carbon fibre, titanium, hardened tool steel. If you're unsure, contact us before ordering.

Do's and Don'ts

✅ Do

Export DXF at 1:1 scale in millimetres
Use closed polylines — no open paths or gaps
Separate cut, etch, and fold lines onto different layers
Include a PDF reference drawing for complex parts
Specify material and finish in your order notes
Add relief cuts at all bend intersections
Annotate critical tolerances tighter than standard

❌ Don't

Include dimensions, text, or title blocks in your DXF
Draw geometry at any scale other than 1:1
Use open splines or unclosed sketch entities
Design holes smaller than material thickness (laser)
Place features within 2mm of the part edge
Leave duplicate or overlapping lines in the cut path
Rely on PDF alone — always provide a DXF or STEP

Ready to upload your file?

Our system checks your DXF automatically and flags any issues before you order.

Upload Your File → Ask a DFM Question
Sign In Get Instant Quote →