Page 12 - HIWT Spring 2012 World of Welding

THE WORLD OF WELDING http://www.welding.org

REPAIR WELDING OF 4130

AIRCRAFT

TUBING

By Elmer Swank, Jr.
AWS CWI/CWE
Technical Instructor
Hobart Institute of
Welding Technology

QUESTION:

We recently had an exhibit at an air show and it seems
a popular alloy with the “do-it-yourself” aviation boys is
4130, since the skeleton of a light aircraft is made of it (or
wood). I saw one of the frames and it is definitely light
stuff. Is TIG the process of choice for repair? If so, which
filler? And a couple said they used oxyacetylene flame to
do repairs. Is this good? And while I’m asking, how about
cutting this thin material?

ANSWER:

Thin wall 4130 tubing is popular for many tubular frame
applications. The 4130 material is high strength, doesn’t
bend easily, and has good weldability. Since the mid-
1940’s, gas tungsten arc welding has been the preferred
welding process. Prior to 1940, oxyacetylene was widely
used. Oxyacetylene preheats, welds, and stress relieves all
in one operation. For “oxy” the filler wire was Oxweld®
32 cm or equivalent. I am not certain if that wire is even
available any more.

With gas tungsten arc welding, ER80S-B2 or ER80S-D2
is used. A preheat of 250 degrees F. is recommended,
although some people don’t preheat at all. Postweld stress
relieving is normally not needed on thin material. Cutting
is mostly mechanical, although plasma cutting will also
work.

HOBART INSTITUTE GRAD EARNS GOLD
(Continued from page 10)

She noticed how old the archery equipment was and how
rundown the archery area in general was. She came up
with a much safer archery area by using a pulley system
to extend the life of the equipment. She actually moved
the archery area to a safer place and made it much more
accessible.
Hobart Institute congratulates Kiersten on her
latest achievement!

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