Insight
Choosing between 3D printing, CNC machining and vacuum casting
A practical comparison for the stage between a CAD model and a production tool: what each process costs, how long it takes, and what it proves.
Three processes cover most of the ground between a finished CAD model and a production tool. The right choice depends less on the part and more on what you are trying to learn from it.
3D printing: fastest, best for geometry
Complete prototypes in as little as 72 hours across SLA, SLS, MJF, FDM and SLM, with 70+ materials from PEEK and PA12 to titanium and stainless steel. Print when the question is does this shape work and when the design is still moving — because it will move again next week, and you will want another iteration.
CNC machining: best for material truth
Three, four and five-axis milling and turning, with material compatibility for steel, aluminium alloy, plastic and artificial wood. Machine when the question is does this behave like the real part — material properties, thread strength, sealing surfaces. You also get the surface treatment options you will use in production: powder coating, laser etching, vapor polish, anodizing, brushing, polishing, electric plating and chrome plating.
Vacuum casting: best for a small batch that looks production
Silicone tooling yields 20 to 25 parts per tool with production-grade quality, in engineering-grade plastics, acrylics and elastomers, up to 2.2 metres in size. Cast when you need parts for a market test, a trade show or a pre-launch build, and when the part has to look and feel like the shipped product rather than like a prototype.
A simple rule
Print to learn whether the design is right. Machine to learn whether the material is right. Cast to learn whether the market is right. Then go to tooling.
