FILIPPA Cutoff Light

Materials by part · one headlight plus the rear light
3D model Materials Drawings

What this is

A bicycle headlight built from scratch: a single 21700 cell, an Osram KW2 CFLNM3.TK emitter behind a LEDiL FILIPPA-STVZO cut-off lens, a four-step driver and an on-board charger. The housing is milled from solid aluminium on a desktop CNC; everything else is either a printed circuit board, a 3D-printed chassis or a purchased part.

Every part below carries its material explicitly. The parts meant for anodising are marked anodise.

Parts to be anodised

Ten parts in two alloys, roughly 0.067 m² of surface in total. Largest part ∅46 mm, longest part 105 mm; the whole set fits a 30 × 20 × 15 cm box. Requested finish is clear anodising 15–20 µm over a glass-bead blasted surface.

QtyPartMaterialStock
No masking is required anywhere. The ∅30 slip fits are bored to size after the bath, against the already-anodised tube; the M2.5 threads are chased with a tap; the seat under the LED board tolerates the oxide (20 µm over ∅20 costs under 0.2 K, against 0.9 K from the board's own dielectric); and no current flows through the housing — the negative return runs on a wire through the end board.

Every part, grouped by material

Notes on the materials

Two alloys. The tubes are drawn 30 × 3 mm EN AW-6060; everything milled comes from ∅50 EN AW-6082 T6 round bar. They sit next to each other in the finished light, so any colour difference between the two after clear anodising is worth knowing about in advance.

The engraved ring is aluminium for now. Brass is a planned upgrade: the part is identical, only the bar stock changes. It would need a barrier against the galvanic pair — lacquer on the back face or a thin gasket.

Fasteners are stainless, not brass. Brass in aluminium under road salt makes a galvanic couple.