Five-Mandrel Coil Spring Winding Block
A hand-held block for winding your own coil springs on 3, 4, 5, 6 or 8 mm steel rod mandrels. Each 22 mm deep slip-fit bore (rod + 0.3 mm) has a flared 1.8 mm wire-feed channel tangent to it, sized for 0.5–1.2 mm music wire. Chuck the rod in a drill, hold the 84 x 28 x 22 mm block and walk it down the rod, and you get a custom spring for a latch, a detent or a robot joint without buying a whole assortment kit.
tool spring-winder music-wire round-stock