Construction Manual
www.oldschoolmodels.com
Page 5
Step 18 - Wing Assembly (cut trailing edge)
Measure and cut one of the
5/16” balsa strips to create the
trailing edge. Glue to all the ribs.
Step 19 - Wing Assembly (create dihedral box)
Carefully cut away the center
of the R1, R2 & R3 ribs, leaving
a box as shown in the photo.
Carefully sand the inside of the
box so the edges are smooth
and flush. This forms three sides
of the dihedral box and needs to
be smooth and free from edges
so the dihedral braces will slide
in smoothly when joining the
wing halves later.
Step 20 - Wing Assembly (cut upper spar)
Lightly sand the edges of the bottom
face of the spar as shown in the drawing
to the right. This will help the spar slide
in easier.
This next part takes a bit of time, so we
recommend against using an instant
setting glue. If you are using CA, use a thicker formulation that
gives you a bit of working time.
Measure and cut one of the 3/16” x 3/8” basswood strips to use
as the upper spar. Apply glue to the top of the ribs where they will
contact the upper spar.
Working from the tip rib (R6), carefully press the upper spar into
position. This will be a tight fit and might require “wiggling” the
spar from side to side to slip in-between the sheer webs. Be sure to
press the spar completely into the slot in each rib, making it flush
with the sheer webs.
Now wick thin C/A along the spar to sheer web joints (front and
back) along the entire length of the spar
When fitting the upper spar to make the top of the dihedral box,
be careful not to drip excess glue into the box formed between
R3, R2 and R1.
Step 21 - Wing Assembly (lower sub-spar)
Carefully remove the wing half
from the board and flip it over.
Measure and cut two of the
3/16”square balsa strips to create
the lower sub-spars. Press them
into position and glue to all the
ribs.
Step 22 - Wing Assembly (SMR install)
Locate one SMR from LP4 and
one TC from BP4. Using the
same technique as in Step 4 -
install a 4-40 t-nut and TC on
to SMR. Once ready, the SMR is
glued into place spanning the
gap between the R5 ribs, with the TC towards the inside of the
wing. Also add glue it to where SMR touches the lower sub-spar
for a bit of extra support.
Step 23 - Wing Assembly (sand R1 flush)
Take a bit of time to sand the
inside edge of the R1 fib flush -
removing excess length of the
spars, sub-spars, leading and
trailing edges.
Step 24 - Wing Assembly (right wing construction)
Set the left (port) wing half aside and begin work on the right
(starboard) wing half. Tape the right wing plan and fresh wax
paper on your board. Then follow steps 1 through 23 to complete
the right wing half. Once finished, then move on to step 25 to
complete the wing assembly.
Step 25 - Wing Assembly (install WH5)
Locate WH5 from sheet LP4
and the left wing panel. The tab
on the end of WH5 will push
into the slot in R2, and WH5
will then fit into the cutout on
R1. Glue into position, but be
careful not to get any excess
glue on the outside of R1.
Step 26 - Wing Assembly (install WH6)
Locate WH6 from sheet LP4.
Again, using the left wing half,
this piece will slide into the slot
in R1, just to the front of the
trailing edge. Push it through
until the tab is located in the
slot of R2. Glue to R2 and to
the inside of R1, again making sure no glue is on the outside of R1.
Step 27 - Wing Assembly (DH1/DH2 install)
Be sure to have some paper towels and rubbing alcohol handy to
clean up any drips and/or fingerprints that might occur during this
step.
Start with left wing
panel and the center
section. Locate two
balsa DH2’s from BP1
and DH1 from LP4.
Note that these pieces
only fit properly one
way. Similar to the
WB1’s from earlier, the
DH2’s have a small circle engraved in them, and this circle should
be positioned to the top and center of the wing.
These three pieces form a “sandwich” of sorts with DH1 fitting
between the DH2’s, then sliding into the dihedral box in one of the
wing halves. Test fit the parts into the slot as shown here. The brace
should snugly slide into each wing exactly half way. Also, the WH5
and WH6 pieces should slide through R1 and into R2.
After test fitting, it’s time to install it permanently with the help
Lightly
sand here.
Lightly
sand here.
