Great Planes Spirit 2-Meter Sailplane Kit - GPMA0530 - Manual (Page 26)

• Work outward, start by tacking the covering in place at the
comers and then start in the middle and work your way out to
the comers, gently pulling any wrinkles out as you go.
• Securely seal all edges! Make sure the edges are firmly
sealed down to prevent the covering from pulling away at the
seams when shrinking the panel.
NOTE: When covering the fin, begin by applying
a 1/2" wide strip of covering on each triangle. Next,
cover the rest of the fin with pre-cut pieces that have
a straight edge to overlap (1/8"+ overlap) the strips
you previously applied. This is a tip you should
remember as it makes it a lot easier to cover
"compound" curves.
Because the fin has to glue on top of the stab and the stab
has to glue to the fuse you do not want to cover where these
surfaces will glue to each other. The following instruction
will explain how to do this.
D 1. Position the stabilizer on the fuselage and aligned
with the fuselage using the procedure at step 3 on page 27.
Hold it in place and mark along the fuselage/stabilizer joint
with a felt pen to show where not to cover.
D 2. Position the fin in place on top to the stab. Make sure
it is centered and pointing straight ahead, and mark around the
base with a felt tip pen.
D 3. When applying the covering to the top and bottom
surfaces of the stab, do each side with two pieces of covering.
Do not cover between the lines. Cut the covering to fit around
the lines before you iron it in place. Also do not cover each
surface of the slab with one sheet of covering and then cut the
covering away between the lines. Doing this leaves "cut
lines" in the wood and greatly weakens the stab structure.
17. Top of left wing panels (overlap covering l/4"at LE
and TE)
18. Top of right wing panels (overlap covering 1/4" at
LE and TE)
19. Spoilers if installed
CHECKING FOR WARPS
This is a very important step and should be done every
once in a while throughout the flying season. A sailplanes
wing is most efficient when it is not twisted or warped at all.
"Washout" (wing trailing edge twisted up at the tip) helps
make a poor wing design fly belter by adding some stability
(preventing stalls) at slow speeds but it cuts down on the wing
efficiency at normal speeds. The SPIRIT'S wing is designed
to fly well at slow speeds without any washout and therefore
we recommend you check to make sure the wings are "flat"
using the following procedure.
D 1. Set the wing so an inner panel is resting on a flat
surface. Any warp (twist) will show up by causing a comer
of the panel to rise off of the work surface.
D 2. To remove the warp, gently twist the wing in the
opposite direction while a helper glides an iron or heat gun
over the covering on both the top and the bottom of the panel
to re-shrink the covering. Hold the twist until the covering
cools and then recheck for warps. It may take several trys to
get a warp out but it is worth it as you will end up with a
sailplane that flies straight and true and responds to air
currents like a high performance sailplane should.
D 3. Follow the same procedure to check all four wing
panels and then go back and double check them. Sometimes
you put a warp in one panel while trying to fix another. You
should also look at the tail surfaces as they too can warp.
Recommended Covering Sequence:
1. Strips as described in above note
2. Fin left side
3. Fin right side
4. Rudder left side
5. Rudder right side
6. Bottom of elevator
7. Top of elevator
8. Stab bottom right side
9. Stab bottom left side
10. Stab lop right side
11. Stab top left side
12. Fuse bottom
13. Fuse sides
14. Fuse top
15. Bottom of left wing panels (inner and outer)
16. Bottom of right wing panels (inner and outer)
GLUE THE HINGES
D 1. Lay the rudder and elevator on the plans and mark on
the leading edge of each part the locations of the hinges. Now
use a sharp hobby knife to cut slits in the covering at the hinge
locations. Trial fit the hinges to make sure you have'' found''
the slots which you previously cut. In the same manner, slit
the covering at the hinge locations in the stab and fin TE.
D 2. When gluing the hinges it is important that plenty of
glue gets inside the hinge slot. If you just put glue on the
hinge, most of it will be wiped off as the hinge is inserted into
the slot. A good way of getting glue into the slot is to scoop
up some epoxy with a plastic soda straw, then pinch the end
of the straw, insert it into the slot, and squeeze the straw to
force the glue into the slot. Apply epoxy to the hinges, insert
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