Austin, Texas - known for the University of Texas, the state capitol and great music - is also home to the Moonlight Towers, which are 165-foot-tall towers that support outdoor lighting for parts of Austin. Thirty-one towers were built in 1895 using electricity from Austin’s first power plant on the Colorado River. They first used carbon arc lamps lit every night by a worker who rode an elevator to the top up the center of the framework. In the 1920s, incandescent lamps replaced the carbon arc and in 1936, mercury vapor lamps were installed. Placed on the National Historic Register, 17 towers are still in use today. In fact, Austin is the only city in the world where the lamps remain.
Through the years, the towers have been used in movies such as “Dazed and Confused,” and are the site of an annual Christmas display. In the mid-1990s the towers were in need of renovation, which meant each tower had to be taken down, unassembled, painted, reassembled and reinstalled.
Because the towers are in a high-traffic area of Austin and are exposed to the elements, which can range from high humidity and temperatures to wind, rain and occasionally snow, it was important that the coating system installed not only beautify the towers, but also withstand the corrosive elements for an extended period of time. Tnemec coating consultant Pat Barry recommended a zinc/epoxy/ urethane system.
After preparing the steel and ductile substrates in accordance with SSPC-SP6/ NACE No. 3, a coat of Series 90-97 Tneme-Zinc, a zinc-rich urethane primer, was applied. User-friendly and rapid-curing, Series 90-97 can be topcoated the same day. An intermediate coat of Series 66 Hi-Build Epoxoline, a polyamide epoxy, was then applied and followed by a topcoat of Series 73 Endura Shield, an acrylic polyurethane. Series 66 has been the industry standard for epoxy coatings for more than 30 years and Series 73 is a semi-gloss polyurethane coating highly resistant to abrasion, wet conditions, corrosive fumes, chemical contact and exterior weathering.
The towers continue to look wonderful years after the 1995 renovation, Barry reports, and remain a popular tourist attraction in Austin.