Construction Manual
www.oldschoolmodels.com
Page 5
FIFTY ONE
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Step 14 - Wing - Leading edge
Locate one of the 5/16" sq. x 36" balsa
strips that will be used as the leading
edge. This fits into the diamond-shaped
cutouts in the front of each rib.
Before cutting it to length, sand a bevel
into one end of the strip as shown here.
The bevel should be roughly 1" long and
take the "point" off the strip. This section
will be positioned on the tip of the wing
(R9) and this bevel helps it fit correctly and give clearance to your
building surface. You may
have to work on this with a
little trial and error to get the
proper fit.
When it's sanded, mark the
length of the leading edge
and cut it, leaving yourself
about a 1/4" extra.
Glue this piece into each of
the ribs as shown here.
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Step 15 - Wing - Top sheeting (part 1)
Locate two of the uncut 1/16" x 4 x 24" balsa sheets. These will be
used to create the wing's top sheeting.
Now this needs to be measured carefully so you have enough
sheeting to cover the top and bottom of the wings successfully
- and here's how we did it.
First, the leading edge piece of sheeting will need to bend
along it's entire length to match the curvature of the ribs. As the
sheeting we get can vary in density, you might need to apply a bit
of Windex® glass cleaner to loosen up the grain and allow it to
bend without cracking. Soak the outer side of the wood to expand
the fibers. Now hold it to curvature needed, use a hair dryer
or covering heat-gun to help “set” the balsa’s bend as it dries.
Once dry, and with the proper bend, it's much easier to make the
following measurements.
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Step 16 - Wing - Top sheeting (part 2)
Place this sheet you just formed up-against the leading edge of
the wing, with the upper-left-hand corner just overlapping R1 by
an 1/8" or so. Temporarily tape this in position.
Now, the second sheet will make up the back half of the sheeting,
but needs to be cut on an angle to roughly match the trailing edge
of the wing.
Position this sheet up against the first piece of sheeting, again
with it's upper-left corner just overlapping R1 by an 1/8" or so.
Temporarily tape this sheet to the first piece of sheeting. Now
you'll need to mark where to cut this second sheet, along the
trailing edge of the wing, leaving yourself a 1/4" or so longer to
play with. When done correctly, this diagonal mark should divide
the sheet into two, roughly equal pieces when cut. (The cutoff
piece of sheeting will be used when sheeting the underside of the
wing later on.)
When satisfied with your measurements, it's time to cut the piece
and in preparation for the next step.
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Step 17 - Wing - Top sheeting (part 3)
When edge gluing the sheeting pieces together, first make sure
the edges are flat (give a quick, swipe or two with a sanding block).
Then tape the two pieces together as
shown here with some masking/painter's
tape. As you lift the sheeting from the
board you’ll see that the tape will act
as a hinge allowing you to put a small
amount of adhesive in the joint. When the
adhesive is applied, place the sheeting
back down on the waxed paper, so that it’s
flat (as shown in the photo). Use pressure
and weights if necessary to hold it flat
along the entire length of the joint. When
cured, remove the tape and you’ll now have a single, wider piece
of sheeting.
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Step 18 - Wing - Top sheeting (part 4)
Glue the leading sheeting up
against the leading edge first
(medium CA works well for this).
Once cured, bend the sheeting
back over the wing and temporarily
tape it in place (or weigh it down).
You'll now need to make a cutout
in the sheeting for WH2. Take
your time and don't try to make
the exact cut the first time. Work
at it, little by little until you have
a great looking cutout.
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Step 19 - Wing - Top sheeting (part 5)
Now apply a slower drying
glue (aliphatic resin and/
or carpenter’s glue) to the
upper framework of the
wing (tops of the ribs, upper
spar, trailing edge, etc.).
Note that a paint or epoxy
brush works great for this.
Then work your way
rearwards, gluing a little at a time. Press the sheeting firmly against
the ribs and weigh it down before gluing the next section of
sheeting - slowly working your way back to the trailing edge, being
careful not to put a bend (warp) in the wing.
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Step 20 - Wing - WH1
Once the glue has dried from
the previous step, carefully
remove the wing panel from the
building board and flip it over.
Locate WH1 from LP3 and glue it
in place as shown here - making
sure the tabs are inserted into
the cutouts in both R1 and R2 ribs. Note that WH1 will stand proud
of the ribs by 1/16", as designed.
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Step 21 - Wing - WH3
Locate two WH3 from LP1. These are
glued between WH1 and WH2, as
shown here - on either side of the pre-
cut hole in WH1.