Choosing a Fabrication Process
Match geometry, load, surfaces, and fit to filament printing or laser-cut sheet construction.
Choose from the required shape and material first
Choose from the required shape and material first
Start with what the part must do. A process is useful only if it can produce the geometry in a suitable material with the required performance.
- Filament printing
- Builds three-dimensional shapes in layers. It suits changing cross sections, bosses, and internal features when those features can be printed and supports can be removed. Layer direction and service temperature affect the choice.
- Laser-cut sheet
- Produces planar profiles from a sheet of existing thickness. It suits flat panels, plates, and repeated outlines. Three-dimensional structures need joints, stacked layers, or another forming operation.
A flat nameplate with surface lettering is a natural laser candidate if the sheet is approved. A one-piece curved knob with a raised boss is a natural printing candidate if a suitable printable material meets the load and temperature requirements. Neither choice establishes production time without a job estimate.
For setup details, use 3D Printing from CAD and Laser Cutting and Engraving from CAD.
Design features the selected process can actually make
Design features the selected process can actually make
- Printed walls and holes
- Check that the slicer generates the intended paths. Leave access for support removal. Do not assume a CAD hole prints at its nominal size; measure a representative sample.
- Laser-cut webs and corners
- Leave enough material between cuts for the part to survive fabrication and use. Account for kerf and heat effects. An infinitely sharp CAD corner does not guarantee an infinitely sharp cut corner.
- Sheet joints
- Design slots from measured sheet thickness and the intended clearance. Kerf compensation controls the cut edge; clearance controls how two finished parts fit. They solve different problems.
- Assembly
- Plan how pieces enter their final position and how they are held. A collision-free CAD assembly does not prove that real parts will fit or can be assembled; see Assembly Files and Mates.
Why there is no universal minimum wall or perfect press-fit allowance
Printer paths depend on nozzle and profile; laser edges depend on the sheet and setup. Material batches and finishing change dimensions too. A small test of the critical feature supplies evidence that a generic dimension cannot. Use Tolerances and Fits to distinguish the intended size from acceptable variation.
Test the critical feature before making the full part; Checklist; Practice
Test the critical feature before making the full part
- State the required shape, material, load direction, surface, and fit.
- Identify the feature most likely to fail: a thin wall, loaded layer joint, supported surface, or mating slot.
- Make an approved small sample that preserves that feature and the intended process setup.
- Measure or test the sample against the requirement. Record the setup and the result.
- Revise the design or setup, then compare time, material, cleanup, and assembly effort before making the full part.