Top Flite TOPA0150 - Manual (Page 12)

Note: Some modelers tend to sand the sheeting too
much after it is applied to the structure, making thin
spots where fingers can easily go through. By
following the procedure above (specifically, by aligning
the joined edges of the sheets as shown in step E),
little sanding should be required. Most of the sanding
that is required should be done before the sheeting is
glued in place. The only sanding that should be
required after the sheeting is glued to the structure is
final sanding with 320 or 400-grit sandpaper.
❏
11. Make four stab skins from the two 1/16" x 6"
x 30" balsa sheets you prepared in the previous
steps (you can get three skins from one sheet, but
will have to use the second sheet for the fourth skin).
Note that the grain is parallel with the LE.
Hint: Make
a paper template and use it to make the skins.
Always cut the skins slightly oversize to allow for
trimming and positioning. Save the leftover sheeting
for the elevators and fin.
Refer to this photo for the following two steps.
❏
12. Glue two of the skins to the top of the stab.
Usually we recommend using aliphatic resin for this
because of the time required for accurate positioning
and adjustment. However, this is a relatively small
stab, so if the skins fit well and you can work quickly,
medium CA may be used.
❏
13. Use the smaller pieces of leftover balsa
sheeting to make four elevator skins. Glue two of
the skins to the top of the elevators.
❏
14. Lift the stab from the building board. The ribs
should slide out from in between the rib jig sticks.
Glue the bottom of the stab center (where you
couldn’t reach when the stab was pinned to the
building board) to the rest of the structure.
Here are a few other things to keep in mind
while sanding balsa sheeting:
1. Make sure you sand the sheets on a flat work
surface that is free from hardened drops of glue or
other imperfections that will damage your
sheeting.
2. Sand the sheeting only as much as required.
The inside of the sheeting needs to be sanded just
enough to remove excess glue and doesn’t have
to be perfectly flat or smooth.
3. Though more material can be removed by
sanding
across the grain, this leaves scratches in
the balsa. Balsa sheeting should be sanded with
the grain—especially when finish-sanding.
4. If some of the glue joints are uneven, it may be
best just to leave them that way, rather than to
sand the sheets too thin. A slightly uneven glue
joint is preferable to paper-thin balsa.
F. Place weights on top of the sheet to hold it flat
while the glue dries.
G. After the glue dries, sand the sheets flat
and even.
E. Press the joining edges of the sheets down to
make sure they are even. This is important. Little
sanding will be required if the sheets are even.
-12-