Tech Notes
T-Section Fabrication
Technical Notes (Contributed by Todd Trainor on 7/29/01)
Since there is no source for the T-section that we could find, my father and I were
forced to make T-section for our 1937 Aeronca K. The drawing is 1-182 Section - T - Standard for the K.
However, I beleive that the T-Section is used on many other pre-war and post-war
Aeroncas. Note that drawing 1-182 Revision C provides a list of alternate
materials. You can use steel or aluminum. I prefer aluminum.
Although the drawing shows the T made by forming one piece of aluminum, we made the
T-section by making two 90 degree Ls and then riveting them together to form a T.
- Obtain 0.020 aluminum and cut it into 1" by 6' strips. We used aluminum
siding for a local siding company.
- Bend each 1" strip into a 90 degree "L" using a break. We used the
break at the siding company.
- Clamp two Ls to form a T using small C-clamps or other clamps.
- Drill the holes for the rivets into the stem of the T. We planned for three rivets
between each rib, with a rivet 1/2" each on either side of the rib and one rivet in
the middle between two ribs. Mark the holes to be drilled by placing the T that is
clamped together in the location where that T will be installed on the wing. Use a
pencil to mark where each rib falls on the T section (to be cut out later) and mark where
to drill the rivet holes. Since T sections are in 6 foot lengths, it will require 3 to fit
one wing span on the top and 3 on the bottom. 6 per wing. 12 per ship.
- Rivet or Pop-rivet the T together. We used pop-rivets.
- Using nibblers, tin snips, and a file, cut out the stem of the T that will fit over the
wing rib. Try to cut away just enough to clear the rib and not too much more, since
the strength of the T is non-existant at those areas. We cut them a little short
(since our pencil markings were less than accurate) and nibbled away more until each
station fit like a glove. NOTE: You must be very careful in handling the Ts once you cut
out the rib spots since there is no strength in those locations and can very easily
buckle, bend, and kink, even under its own weight.
- Nail the T onto the wing. We drilled #60 pilot holes into the T first.
Naturally, approval of this replacement of the original T-section is subject to your
FAA inspector. This is not a formally approved FAA replacement part and is not
represented as such.
