In the D3D Universal 3D printer extruder, we are using 1.25 mm spring steel - or 0.05 inch wire.

Welding wire is 0.035" - close to the diameter - but much lower strength - at 70ksi.

Spring steel wire is 260 ksi - about 4x stronger! [1]

Kevlar is about 520 ksi. (3620 MPa)

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