Parametric CAD

A model is built on dimension variables: change the 'wall thickness' parameter and all geometry recalculates. Unlike 'drew what fit' — a part adapts fast to a new material or size.

Fusion 360 (free personal license) — the 3D-printing standard. FreeCAD — open source, parametric, steeper curve. Onshape — cloud, free public tier. TinkerCAD — for starters and kids.

Order: sketch → constraints → extrude → parameters. First define 5–10 key parameters (diameters, thicknesses, clearances), then model from them — not the reverse.

45° angles need no supports, holes +0.2–0.4 mm for shrinkage, layer strength: load along layers, not across. Fillets over sharp corners — less stress and warping.

First project — not an ornament but a real thing: a mount, bracket, organizer. Fusion 'for 3D printing' YouTube tutorials — 10–15h of practice covers 90% of home tasks.