I was inspired by Adam Savage's One day build video of the Iron Giant Bolt to make one of my own.
I didn't find any 3D models online, so I decided to model it myself. Measurements were from screen grabs of the movie based on a 9-year-old's average hand size, so it's about 6" tall.
The IG-Tube-Top is to be inserted between the screw threads and screw head to hold together. The IG-Tube-Bottom goes between the screw thread and bottom cone.
The center area of the bolt head is hollow to add LEDs and wiring. (may need to hollow out more).
Parts modeled in 123 Design and exported parts run though NetFabb. You only need supports for the screw threads.
If you have other sets of measurements that you think are better or other suggestions to improve it, please let me know.
First print is done as pictured. Need to clean up the remaining support material in the threads, glue together, paint and light it.