VERSION 1.2 is available here: https://www.thingiverse.com/thing:5171637
with this new version, you can now use piano wire in order to make much improved springs

Instant springs with this 7 grams (0.25 oz) spring factory.
Works with 0.5mm to 1.5mm steel wires.

This machine does not have the capacity to make real spring-steel springs, which limits the mechanical characteristics of the spring obtained. But if your load is low, these springs can help you out. I'm currently working on a new reinforced version that would work with spring-steel metals, and produce more efficients springs.

Watch the video in order to see how it works : https://youtu.be/LC6OpSbCAPU

On the video, i used 25 centimeters (10 inches) of 1.5mm stainless steel wire.

Print Instructions:
Just print the two things with the classical 0.4 nozzle. There should be no problem with clearance.
No need for supports.
No need for raft
Layer Height= 0.2 (probably works with 0.28 layer height, but i did not try)
Use 5 walls, 4 top layers and 4 bottom layers.
20% infill is enough.

printed on an ender3 V2, using cheap GST3D PLA filament (8€ / kg). Total cost is around 6 cents with this PLA, and probably a bit more than 10 cents with other brands..

Printing time: Bolt= 20 minutes Screw: 58 minutes at 50mm/s

Final spring has a 9mm external diameter. length is about 32mm