View source for Diy: Voice coil actuator

== Introduction ==

For a small mirror scanner:
* Coil diameter: 8–15 mm
* Coil height: 3–8 mm
* Wire: AWG 34–38 (0.16–0.10 mm)
* Turns: 100–300

More turns:
* More force per amp
* Higher resistance
* Lower current
* More moving mass

Fewer turns:
* Lighter
* Faster
* Needs more current

A good starting point is 150–200 turns of AWG 36. That usually gives a resistance around 8–20 Ω, depending on the exact dimensions. 

Current Typical ranges:
* Testing: 20–50 mA
* Small scanner: 100–300 mA
* Fast scanner: 300–800 mA

Use neodymium magnets, not ferrite. N Coil S. 

Restoring force. Thin spring steel. Piano wire (A 0.3–0.5 mm piano wire can act as a torsion spring). Flexure hinge. 

For larger mirrors, miniature bearings can be used. Eg 2×5×2.5 mm or 3×8×4 mm

Inkjet printers, Speakers, Old toys.