Rocket Sundial is located at the China Lake Museum

Rocket Sundial is located at the China Lake MuseumRocket Sundial

Designer and fabricator: John P. “Skip” Gorman – It was ZJ Hoffmann (Eagle Scout candidate) who contacted me in early April, 2021, with the idea of making a sundial using a 2.75-inch rocket as his Eagle Scout project. The novelty of this combination was irresistible to me so I agreed to become involved in his venture.

An Idea Whose Time Has Come. The Rocket Sundial uses a 2.75 inch Wrap Around Fin Aerial Rocket (WAFAR) as its gnomon. It is located at the China Lake Museum, 130 E Las Flores Ave, Ridgecrest California

The concept of using the Navy supplied (Inert Certified) rocket as the sundial gnomon projecting from a dramatic “shockwave plane” (which contained the Roman numeral hours) occurred instantly to me. There was no creative ordeal involved. My challenge after that was designing the shape of the shockwave plane (the clock face) and then designing an overall mechanical structure which positions the rocket gnomon properly to the clock face and then composing the entire structure as a functional sundial.

I made a sketch and passed it to ZJ (who liked it) and got cracking on a half-scale prototype (as is my style for projects such as this). I literally “went to school” on sundials for a while and I found that they are surprisingly complicated. ZJ shared with me a sundial designing website which I found instructive. I used it to determine the (non-linear) angular distances between the time increments and also the elevation angle required of the gnomon at our latitude. Beyond that I used our location to determine the Magnetic Declination (11.9 degrees) between True North and Magnetic North this year.

The half-scale prototype came together using 12-gage cold rolled steel (about 1/8” thick). The idea of standing the Roman Numerals upright radially on the clock face allowed me to exercise my slot-tab invisible weld technique and fit well into the shockwave character of the piece. I wasted some time trying to engineer an adjustment which would allow for the naturally changing Declination (about .2 deg/year) but gave it up after a while. ZJ came up with the Latin phrase for the sundial (Which is, “Time Rules All”).

After fussing with the prototype a bit I obtained a full sheet and a half of quarter-inch steel plate and began plasma cutting it and welding it up. I polished off the mill scale from the top of the clock face and gave it a thin copper plate with an aged and heat-distressed appearance which was then finished with several layers of Rust-oleum clear coat. It should age (like us all) gracefully.

Story First Published: 2021-10-15