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4.
Check to see that all is aligned properly, then use thin CA to glue the parts together.
5.
Add the upper spar, check to see that it is fully seated into the rib notches and flush with
the sheer webbing, then glue.
6.
Place and pin the bottom sheeting into place using the wedges to pull it up against the
ribs as before.
7.
As with the center section and mid-wing, install the sub-leading edge.
8.
Shape the sub-leading edge to the rib profile.
9.
Install and trim top sheeting.
10.
Install the leading-edge.
11.
Shape the leading-edge profile.
12.
Add the tip outboard triangular gusset at R22.
13.
Sand spars, webbing, and sheeting on the ends of the tip flush with the existing ribs.
Repeat for the other wing tip if not building the two concurrently.
Attaching the Tip to the Mid-wing
1.
Pin the mid-section securely to the building board.
2.
Trial fit the mid-wing and the tip together. Sand the polyhedral braces as needed to fit
between the pine spar caps.
3.
Make any adjustments needed to fit R19 tightly against R18 and the two pieces of trailing
edge together without gaps.
4.
Set the CG jig under the outboard end of the tip
section, bracing it on the notches (as shown).
5.
Practice assembling the pieces several times. You will
be rewarded! Check to see that the rear polyhedral
brace fits correctly along the tip trailing edge.
6.
Glue the tip and the mid-wing together. Some builders
prefer using epoxy here to take advantage of the
longer setting time. Clamp and pin as necessary to
line up the two sections as perfectly as possible.
Repeat for the other side.
Building the Winglet
The “winglet” is the upward extension at the end of the wing tips, and is used to decrease
wingtip vortices, thereby reducing drag. Many builders find it easier to build the wing tip as two
separate pieces. The winglet is then attached to the tip and the entire assembly glued to the mid-
wing to form a solid unit.
Figure 29: CG Jig Used to Set Polyhedral Angle