Vacuum Casting Materials

Material selection depends on four key factors:

• Mechanical requirements — hardness, flexibility, impact strength
• Thermal requirements — maximum operating temperature
• Appearance requirements — transparency, colour, surface finish
• Regulatory requirements — flame retardancy, RoHS/REACH compliance

As a general guide:

• Rigid housings and functional parts → ABS-like resins (e.g. PU8150, Axson PX 100)
• Lenses, covers, display panels → PMMA-like / acrylic-like resins (e.g. PX 522 HT, UPX 5210)
• Grips, seals, overmold simulations → Rubber-like urethane (e.g. UPX 8400, Shore A 20–85)
• Electrical enclosures, safety-critical parts → Flame retardant UL94 V-0 resins (e.g. Hei-Cast 8263)
• Snap-fits, living hinges, packaging → PP-like / HDPE-like resins (e.g. Hei-Cast 8550)

Yes — both are fully supported.

For transparent parts, we use PMMA-like resins such as Axson PX 522 HT and UPX 5210, which deliver water-clear optical clarity comparable to acrylic. Parts can be sanded and polished to a high gloss after casting. Maximum cast thickness for clear parts is up to 50 mm.

For coloured parts, pigment is mixed directly into the liquid resin before casting. We can match standard RAL or Pantone references. Because colour runs throughout the material — not just as a surface coating — scratches do not reveal a white core, as they would on painted parts.

Parts can also be painted after casting for precise colour matching, metallic effects, or two-tone finishes.

A standard RTV silicone mold typically yields 20 to 25 parts under normal casting conditions. Actual mold life depends on:

• Part geometry — deep undercuts, sharp features, and thin walls accelerate mold wear
• Resin type — filled or abrasive resins (e.g. glass-filled grades) reduce mold life faster than standard polyurethane
• Transparency requirements — clear parts require stricter mold condition standards; a mold suitable for opaque parts may only yield 10–12 acceptable clear parts

If your project requires more than 25 parts, we simply cast a second mold from the same master pattern. For quantities above 100–200 pieces, we will advise whether injection molding tooling becomes more economical for your specific project.

Our standard dimensional tolerance for vacuum cast parts is ±0.15 mm per 100 mm, with a best achievable accuracy of ±0.05 mm for well-designed parts using high-quality master patterns.

Key factors affecting final accuracy:

• Master pattern quality — a CNC-machined master delivers tighter tolerances than a 3D-printed one
• Material shrinkage — all polyurethane resins undergo slight shrinkage during cure (typically 0.1–0.3%); this is compensated in the mold design
• Part size — deviation accumulates over larger parts; call out critical features explicitly on your drawing
• Wall thickness — minimum 0.75 mm required; 1.5–2.5 mm recommended for best results

For parts with tight tolerance requirements on critical mating surfaces, mark these dimensions on your drawing and our engineering team will evaluate feasibility before production.

Maximum part size is limited by our vacuum casting chamber dimensions. We can accommodate molds up to 1,900 × 900 × 750 mm (L × W × H), with a maximum part volume of approximately 10 litres.

Wall thickness guidelines:

• Minimum: 0.75 mm (required for proper mold fill)
• Recommended: 1.5–2.5 mm for consistent fill quality and part strength
• Maximum: no hard limit, though very thick sections may require extended cure times or risk internal voids in some resins

Transparent parts cast in PMMA-like resin can be produced in sections up to 50 mm thick while maintaining optical clarity.

Yes — most ABS-like and PMMA-like resins accept paint and surface treatment very well.

Available post-casting finishing options:

• Painting — primer + top coat in gloss, semi-gloss, matte, or textured finishes; RAL and Pantone colour matching available
• Polishing — for transparent PMMA-like parts; sanding through progressively finer grits to achieve optical clarity
• Texture replication — chemical or mechanical texture applied to the master pattern is reproduced in every cast part
• Decorative chrome / metallic plating — for appearance models and consumer product samples
• Insert embedding — threaded brass or stainless inserts can be cast in place for functional assemblies

Note: rubber-like (Shore A) parts are more challenging to paint due to flexibility — adhesion promoter is required, and only flexible paint systems should be used.

Minimum order quantity (MOQ): 1 part.

We accept orders from a single prototype to batches of 50+ parts from one mold.

Typical lead times from receipt of your approved 3D model:

Rush orders may be accommodated depending on current workshop capacity — contact us directly to discuss your timeline. For orders requiring 50+ parts, we recommend planning for two mold cycles (approximately 18–20 working days) to maintain consistent quality.

The decision comes down to volume, timeline, and tooling budget.

• Choose vacuum casting if you need fewer than 100 parts, want to avoid $5,000–$50,000+ in injection mold tooling costs, or need parts in 1–2 weeks. It is ideal for design validation, functional testing, customer presentation samples, and bridge production before mass manufacturing.
• Choose injection molding once your design is finalised and volumes justify the tooling investment — typically 500+ parts per run. Injection molding offers tighter tolerances, longer mold life (100,000+ shots), and lower per-part cost at scale.

The most common workflow:

Validate your design with 10–30 vacuum cast parts → confirm form, fit, and function → invest in injection mold tooling for mass production.

Our team can advise on the crossover point for your specific part geometry and volume. Request a quote for both processes to compare cost and lead time side by side.