Well, here's something fun:
Just finished these up for the last group of people who ordered them through my Etsy shop and they're all updated with the new rounded "left eye".
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But, whether fortunately or unfortunately, they aren't the perfectly rounded green-painted-black marbles or eyes (or whatever they are) as the original seems to indicate. No, because of my skull, I had to settle for something that I could get away with within budget and still, at least, resemble the original thing.
View attachment 496455
They're casts of modified carriage bolts I picked up from the hardware store. They're hemispherical so they sit better against the "eye cavity" of my bird skull. Same goes with the nut; can't use an acorn nut, gotta stay true with the hex.
One thing that I'm not going to change in light of the new stuff discovered in this thread is the guide rod. It's practicality of helping keep my bobble stable (from wobbling so far it becomes unbalanced) is too handy to sacrifice. It's going to remain a steel rod, for me.