3D printing or CNC machining: which one you want
When printing wins and when machining does, by quantity, material, tolerance and geometry. Without overselling either.
We are a 3D printing workshop, so it is only fair to start where we lose: if you need a hundred aluminium parts to hundredths of a millimetre, do not call us. Call a CNC shop.
| Criterion | 3D printing | CNC machining |
|---|---|---|
| Quantity | 1 to 500 | From 10, better the more |
| Complex geometry | Free | Every corner costs |
| Typical tolerance | ±0.3 mm (±0.1 in resin) | ±0.05 mm or better |
| First part | Hours | Days, with fixturing |
| Metals | Not in our workshop | Their ground |
The question that actually decides
Are you going to change the design again? If the answer is yes — and in prototyping it almost always is — print it. Changing a printed model costs a new file and a few hours. Changing a machined part can cost new fixturing.
The pattern we see over and over: three or four printed iterations until the shape is right, and only then, if the volume justifies it, a move to machining or moulding. Using printing to validate before spending on tooling is by far its most profitable use.