Install The Fin - GREAT PLANES Ryan STA Instruction Manual

4. Turn the fuse upside-down. Stick a T-pin through the
bottom of the fuse centered over the middle stringer. Tie a
small loop in one end of a 50" piece of non-elastic string
such as monofilament or Kevlar fishing line. Slip the loop in
the string over the T-pin.
5. Fold a piece of masking tape over the string near the
other end and draw an arrow on it. Slide the tape along the
string and align the arrow with one end of the stab as shown
in the photo. Swing the string over to the same position on
the other end of the stab. While keeping the stab centered,
adjust the stab and slide the tape along the string until the
arrow aligns with both sides of the stab. Be certain the stab
remains centered, side-to-side, during this process.
6. Use a fine-point felt-tip pen such as a Top Flite
Line Pen (TOPQ2510) to mark the outline of the fuse onto
the top and bottom of the stab.
7. Remove the stab. Use a sharp, new #11 blade to trim
the covering from the stab along the lines you marked. The
same as when you cut the covering from the wing, use care
to cut just through the covering, thereby not cutting into the
wood. Important: Cutting into the balsa will weaken the stab
which could cause it to break during flight. Using a sharp
blade reduces the pressure required to cut the covering,
thereby reducing the chance of cutting into the balsa.
8. Peel the covering from the stab. Remove any ink with
a piece of a tissue dampened with denatured alcohol.
9. Thoroughly coat all joining areas of the stab and fuse with
30-minute epoxy. Reinsert the stab into the fuse. Wipe away
excess epoxy using tissue dampened with denatured alcohol.
Center the stab the same way you did before (measuring the
distance from side to side and using the pin-and-string). Do not
disturb the fuse until the epoxy has fully hardened.
1. Test fit the fin into the fuse. Be certain the trailing edge
is even with the aft end of the fuse. If the fin cannot be
positioned far enough aft to achieve this, trim the bottom of
the trailing edge of the fin.
2. The same as you did the stab, draw a line around the
fin where it meets the fuse. Remove the fin and carefully cut,
then remove the covering.
® Panel
3. Use 30-minute epoxy to glue the fin to the fuse. Before
the epoxy hardens, use a Hobbico
(HCAR0480) to check if the fin is perpendicular to the stab.
If necessary, use masking tape to pull the tip of the fin to one
side or the other until it is "square."
4. The same as you did when hinging the ailerons, drill a
3/32" hole, 1/2" deep in the center of the hinge slots in the stab,
fin, elevators and rudder. Cut the covering from the hinge slots,
then cut nine hinges from the remainder of the CA hinge strip.
10

Install the Fin

® Builder's Triangle