Seven-Radius Fillet Gauge Card
This flat 150 x 60 x 3 mm card checks radii. It has semicircular notches (for outside rounds) and matching tongues (for inside fillets and grooves) at R2, 3, 4, 5, 6, 8 and 10 mm. Use it to read the corner radius off a broken appliance tab, handle or knob before you model the replacement. Each radius is marked by a column of pin dots, one dot per millimetre, and a 6 mm hole at one end lets you hang it on a pegboard.
tool radius-gauge fillet measuring