SkillsProto logo Get a Quote

Case Study: Motorsport Aero Package

Industry: UK independent motorsport team (Touring Car class) Processes: CNC machining (aluminium 6061 tool/mould components) + FRP composites (carbon fibre lay-up, vacuum bag) Quantity: 1 prototype set + 3 production sets Lead time: 18 working days end-to-end Outcome: +18% front downforce, -2.1 kg mass vs. previous GRP-only design, on-car fit confirmed at first fit-check.

This is an illustrative case study based on a typical SkillsProto motorsport project. Client and team names are anonymised.

Background

A UK-based Touring Car team approached SkillsProto to redesign their front splitter and rear diffuser package ahead of the 2026 season. The previous design was GRP-only and was failing both on stiffness (visible flex under load) and on weight budget.

They needed:

  • Stiffer aero surfaces to maximise grip.
  • Lighter than the incumbent GRP package.
  • Fast enough to test on the rolling-road rig before the first race of the season.
  • Mounting hardware that bolted directly to the existing chassis hardpoints without modification.

The SkillsProto solution

We designed the package as a multi-process assembly with three integrated components:

  1. Aluminium 6061 splitter plates and diffuser vanes — CNC machined from billet, hard anodised for wear resistance on kerb strikes.
  2. Carbon fibre outer skin — wet lay-up with vacuum bag consolidation, 2x2 twill 3K weave, clear coat satin.
  3. CNC machined aluminium mounting brackets — drilled and bolted to OEM chassis geometry.

A single project manager owned the whole package, with one quote, one lead time, one FAI report.

Process breakdown

CNC machined aluminium splitter plates

  • Material: Aluminium 6061-T6 plate, 8 mm thick.
  • Tolerances: ±0.1 mm on bolt-hole pattern; ±0.05 mm on critical reference edges.
  • Finish: Type III hard anodising (50 µm) for wear and kerb-strike resistance.
  • Quantity: 4 plates (1 prototype + 3 production).
  • Lead time: 6 working days including anodising.

CNC machined diffuser vanes

  • Material: Aluminium 6061-T6, 6 mm plate.
  • Geometry: 12 thin curved vanes per side, each 280 mm long.
  • Tolerances: ±0.1 mm on the vane profile (affects airflow separation).
  • Finish: As-machined + bead blast for uniform matte appearance.
  • Quantity: 24 vanes (12 per side, 2 cars).
  • Lead time: 7 working days.

Carbon fibre outer skins

  • Process: Wet lay-up + vacuum bag.
  • Material: 3K twill carbon fibre + epoxy resin.
  • Lay-up: 3 plies at 0/±45 for balanced stiffness.
  • Core: PVC foam 6 mm for panel stiffness.
  • Finish: Clear coat satin.
  • Quantity: 6 panels (2 splitter outer skins + 2 diffuser outer skins + 2 spare).
  • Lead time: 12 working days including mould prep.

CNC machined mounting brackets

  • Material: Aluminium 7075-T6 (high fatigue resistance).
  • Tolerances: ±0.05 mm on bolt-hole pattern.
  • Finish: Anodised black (Type II).
  • Quantity: 12 brackets.
  • Lead time: 5 working days.

DFM feedback during quoting

We flagged two manufacturability issues before cutting any metal or laying any carbon:

  1. Original splitter mount design had a thin wall section (0.8 mm) that would have been difficult to anodise evenly and would be vulnerable to kerb-strike cracking. We redesigned the section to 2.0 mm with a localised reinforcement rib — no cost impact, better performance.
  2. Diffuser vane radius was specified as R0.5 mm which is below our recommended R1.0 mm minimum for clean anodising. We adjusted the radius to R1.0 mm — flow impact negligible at this radius, anodise quality dramatically better.

Both changes were agreed with the team in one round-trip.

Quality and inspection

  • First Article Inspection (FAI) on every part — dimensional report with CMM measurements on the splitter plates and diffuser vanes.
  • Visual inspection on all carbon panels — no porosity, no dry spots, consistent weave orientation.
  • Hardness test on anodised surfaces — verified 50 µm coating thickness.
  • Fit-check at our Shenzhen factory before shipping — all mounting bolts torqued to spec, panels aligned, package shipped as a matched set.

Logistics

  • DDP shipped to UK via air freight.
  • Total transit time: 5 days door-to-door.
  • Customs documents: commercial invoice, packing list, certificate of origin, EUR1 movement certificate for preferential EU-UK duty.

Outcome

  • +18% front downforce measured on the team's rolling road vs. previous GRP-only design.
  • -2.1 kg total mass vs. previous GRP package.
  • First on-car fit confirmed with no chassis modification required.
  • No warranty issues after the first race weekend (3 sessions, including one kerb-strike incident where the hard-anodised splitter plate survived intact).
  • The team ordered a follow-up set for their second car within 4 weeks of the first delivery.

Lessons and what we learnt

  • Multi-process assemblies deliver the best results when one project manager owns DFM, lead time and QA across all processes. We saved the team 3–4 days vs. coordinating multiple suppliers.
  • Anodising on CNC aluminium is the right call for any wear or kerb-strike surface. The hard anodise layer saved the splitter plate in their first incident.
  • DFM at quote stage catches the geometry issues that would have caused field failures. The thin-wall change on the splitter mount cost us 2 hours of CAD time and saved the team a probable season-ending failure.

Get a similar project quoted

Send your CAD, expected volume and lead time for a multi-process assembly quote. We will DFM-review every part and return a single quote covering all processes and finishing.

[Request a Quote — Multi-Process Assembly]