Not an astrolabe.Process:The "Cosmolabe" was made of layered brass sheets:I did the designs for the markings in Illustrator, printed them out reversed and inverted on a transparency from a laser printer, ironed them onto the brass (with judicious use of a sharpie for clean-up) and acid etched them with the circuit board fluid you can get at Radio Shack. Then I cut out the pieces with a jeweler's saw and filed them smooth. The permanently fixed pieces were riveted together using small brass brads.