Sequoia Aircraft Corporation F.8L Falco, Construction Manual

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F.8L Falco Construction Manual 20–3 Revision 4, March 1, 2002
Trailing Edge Rib Installation
In the following steps, the trailing edge ribs will be installed on the spar. It will be important that
you maintain the alignment of the trailing edge. You will find that once things are glued in place,
there is relatively little opportunity to make an adjustment, so it is best to get things aligned from
the beginning. This is complicated by the fact that the trailing edge strip is a constantly-tapering
triangular strip of spruce.
The ribs should be aligned with a string. In addition, boards may be clamped to the sides of the
ribs to stabilize them.
If you want to cover the rudder with fabric, see Figure 4. Note that the trailing edge strip is 30mm
wide and each rib is joined to it by a 15mm deep notch in the trailing edge strip.
Figure 5
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Fit the trailing edge ribs for Sta. 0 and 5. See Figure 5. The Sta. 0 rib must be centered
between the channel-nuts for the control arm. Since a string will be used for aligning the
ribs, a brace should be made of wood to support these two ribs to keep them from “leaning”
due to the tension of the string.
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Sand these two trailing edge ribs to the angle required for the trailing edge strip.
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Glue the trailing edge ribs for Sta. 0 and 5 in place. Scuff-sand the plywood before gluing.
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Loop a string over the ends of these two ribs to align the other rudder trailing edge ribs.
See Figure 5.
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Fit the trailing edge ribs for Sta. 1, 2, 3 and 4. Do not fit the Sta. 0 diagonal rib at this
time. See Figure 6.
Figure 6
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Sand these trailing edge ribs to the angle required for the trailing edge strip.