Gear Rack (module 2, 12 teeth)
A 75.4mm rack in module 2 — twelve teeth at 6.28mm circular pitch, 15mm face, on a 6mm backing bar. A rack is a spur gear of infinite radius, which is why its flanks are dead straight and lean at exactly the 20° pressure angle. Same ISO 53 proportions as the gears above — 3.14mm of tooth on the pitch line, 2mm above it, 2.5mm below, 0.38×module root fillets — so any module-2 gear here rolls along it properly. A module-2 20-tooth pinion gives 125.7mm of travel per turn. Butt several end to end for a longer run: the tooth spacing carries across the joint because the first tooth starts half a pitch in. Prints teeth-up, flat on the bed; the steepest face is a flank at 20° off vertical, so no support. PETG.
from £3.72example, in PLA
Example pricing
A guide only — not a fixed quote. Final price depends on material, quantity, print orientation and printability.
| Material | 1 unit | 5 units | 10 units | 25 units |
|---|---|---|---|---|
| PLA | £3.72 | £15.62£3.12/unit | £28.27£2.83/unit | £63.22£2.53/unit |
| PETG | £3.94 | £16.55£3.31/unit | £29.95£3.00/unit | £66.99£2.68/unit |
| ABS / ASA | £4.44 | £18.66£3.73/unit | £33.77£3.38/unit | £75.53£3.02/unit |
Per-unit prices fall with quantity. Larger batches are cheaper still — ask for a bulk quote.