The most crucial part of a weathervane is its spine.
A weathervane’s spine is the Post & Spindle (mast, rod, pin, pole, post, shaft, etc.). A post has 3 sections. The bottom of the post is the foot which plants the weathervane. The middle section is the trunk consisting of the compass directionals, balls, or other ornaments. The short, thin portion at the top is the spindle which disappears into the weathervane figure. Inside the figure is a bearing so the figure hangs and rotates on this pivot point.
There are 3 basic types of posts; the shaped cast aluminum posts used for the wrought iron look weathervanes, the economy threaded steel posts, then the welded rod and pin posts in stainless steel, and bronze which are the superior product.