The Experimental Aircraft Association (EAA) is an international membership organization which focuses on aviation and the broad range of activities it offers. Committed to making aviation more accessible to all who wish to participate, EAA maintains high standards in regard to the design, building, restoration and maintenance of aircraft. Part of achieving and maintaining those standards is the job of Gerard Putzer, aircraft maintenance technician at EAA.
With tasks that range from simple welding repairs to fabricating a new carburetor heat box for EAA’s “Spirit of St. Louis” replica, Putzer relies on his Miller Econotig AC/DC TIG/Stick welder. He credits TIG welding as the most versatile welding process. “This process lends itself well to our purposes because we weld a variety of metals every day,” says Putzer. The Econotig welds any metal using a non-consumable tungsten electrode and a single shielding gas which protects the weld area from contamination.
TIG units are also able to pinpoint heat control and precisely adjust the amount of heat applied to the surface. This is especially useful because aesthetics of the aircraft on display at EAA’s Air Adventure Museum are very important.
EAA Fly-In Convention
Perhaps the most famous aspect of EAA is its annual Fly-In Convention in Oshkosh, Wis. Each summer more than 800,000 people and 12,000 airplanes attend the week-long celebration of flight. In 1995, 72 nations were represented at the event, which is considered to be among the world’s largest and most significant aviation events. Many of the world’s top aviation officials take part as well.
This annual event is also a busy time for welding operators at EAA. According to Putzer, “We do whatever we can to support the air show performers in the way of maintenance or repairs.” He describes a time when an EAA show performer’s exhaust system was extremely deteriorated. Putzer repaired the stainless steel exhaust system with his Econotig. “TIG welding is ideal for stainless steel,” Putzer says. “We got him back in the air and he continued our show.”
Many aircraft come in to the EAA hangar with parts which are no longer operational. When an airplane is more than 50 years old, spare parts are hard to find. In many cases, Putzer fabricates new parts using his Econotig and duplicate plans on microfilm of the structural engineering drawings provided by the Smithsonian Institution.
One of the most important aspects in building new parts for the old airplanes is precision. Being able to preserve the integrity of the original design is a credit to EAA. “Using a carburetor heat box like the type Lindbergh used as a pattern, we were able to make a new one using 6061 aluminum and the TIG welding process,” he explains. “We can literally build many things back to their original spec, including the type of alloys used.”
Another example of the utility of TIG welding occurred when the tail wheel lock pins of a B-17 became worn. To fix this, a plate had to be welded on to the end.
“The TIG welding process worked ideally. It came out right to spec. The original called for a plate to be welded at precisely that position,” Putzer says. “The welding process was fast, very accurate and it looks every bit as nice as the original.”
Information courtesy of Miller Electric