This is a picture of customized brass nuts, which are used as supplementary parts for rigging. I usually make my armatures in various materials including alloys of steel and aluminum as well as brass. Some clients specifically order brass armatures.
Brass is highly machinable and offers greater corrosion resistance than steel. It is also easy to braze and weld thanks to its relatively low melting point.
Even with such advantages, however, stop-motionists in some countries have underestimated brass as a material for armatures. They say that brass is weaker than steel and corrodes under alkaline conditions.
It’s true that brass has some disadvantages, but I still think brass is a very good material for armatures. With a brass armature, it is possible to create smoother movements and control tension more precisely than armatures in other materials.