SIG Wonder Instruction Manual

Sig Mfg. Co., Inc...401
-
7 South Front Street....Montezuma, Iowa 50171
Introduction by Bruce Tharpe
People often ask me what the inspiration was for the Wonder. Well, did you ever see the Flying Sub from "Voyage to the Bottom
of the Sea"? As a kid, I thought that was just about the coolest flying machine ever conceived. No, the Wonder doesn't look
exactly like the Flying Sub, but it had to be somewhere in the back of my mind when I was doodling the first Wonder years ago. I
suppose there's a bit of old
-
time control line combat influence in the design as well.
The design presented here actually evolved from many years of "Wonder-Type" designs, starting with 1/2A versions back in the
early 1980s. There have been swept wings, straight wings, single tails, twin tails, and tripple tails. The basic idea has never
changed, however. I wanted dirt-simple models that featured a shoulder wing (for easy hand launches) with a large stabilizer
butted up against the trailing edge. Many people call them flying wings, but technically, they're not. Actually the extended tail
simplifies hooking up the ailerons and elevator, and provides a smoother pitch response than most true flying wings.

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The main goal was always to create a smooth-flying, aileron-and-elevator-controlled aerobatic ship. The design in this box is
definately the best of the Wonder bunch!
The Sig Wonder kit has been engineered to provide the builder with four optional versions as shown above. The basic structure
of each version is identical - the dfifferences are cosmetic. There's no perceptible difference in the flying qualities of one over
another, so pick the version that "turns you on" the most.
If you're feeling creative, go ahead and mix fins from one version with ailerons from another and a canopy from a third to create
your own, personal version. All of the decals are provided, so you can intermix those as well.
Incidentally, if you get a chance to see a rerun of "Voyage to the Bottom of the Sea", be sure to check it out. Somehow the
stories seem dumber than they were so many years ago, but the Flying Sub is still pretty cool.
ENGINES, PROPELLERS, AND MUFFLERS
The recommended engine range for the Wonder is .09 to .19 cu. in. There is a tremendous variety of engines available in this
range. Remember that weight is the mortal enemy of small models like this Wonder, and as you go up in power you also wind
up increasing the weight. That's not to say than an .09 powered Wonder performs as well as a ,19 powered Wonder, but the
difference is probably less than you would expect. Most modellers will be completely satisified with a good .15 in the nose. The
real power lovers who enjoy ballistics over aerodynamics will have to install a .19. Anything bigger is not recommended by Sig.
Use only those propellers recommended in the instructions supplied with your engine. And use a muffler! A loud engine may
cost you (and possibly your club) the use of your flying field if it annoys a non-flying neighbour. Use the muffler that came with
the engine or one of the many after
-
market mufflers that are available.
RADIO REQUIREMENTS
The Sig Wonder uses only two flight controls: ailerons and elevator (there is no rudder). Throttle control is optional but is highly
recommended. Standard size servos can be used (see plan), but do yourself a favour and buy some mini or micro servos that
are compatible with your radio system. The smaller servos will be much easier to install in the Wonder and will save some
weight, too. A small, flat 225 maH to 300 maH battery pack is a must. Be certain your radio system frequency is approved for
use in R/C model aircraft.
GLUES
There are many different glues available today for model construction that it can be confusing to even the experienced modeler.
To simplify matters, most glues can be classified as one of four basic types: Fast cyanoacrylate adhesives (abbreviated as CA)
such as Sig CA, easy to use water-based wood glues such as Sig-Bond (yellow) and Sig Super-Weld (white), super strong (but
heavier) two-part epoxy glues such as Sig Kwik-Set (5 minute cure) and Sig Epoxy (3 hour cure), and traditional solvent-base
model cements such as Sig
-
Ment.
Each of these types has different characteristics and advantages. Often times, the choice of which type to use is strictly a matter
of personal preference based on your experience with previous models. CA is recommended as our first choice because of it's
ability to penetrate an already assembled joint. In other words, parts can be assembled dry (without glue). the alignment
checked and adjusted, and then the glue can be applied to the joints. You should also have on hand some epoxy (both 5-
minute
and slow dry) and Sig
-
Bond because these glues are called out in several of the steps in these instructions.
Sig CA, like mose brands of cyanoacrylates, come in three viscosities- thin, medium, and thick. Odorless CA is generally more
expensive, but it is ideal for people who can't tolerate the fumes of normal CA. An accellerator spray and debonder are also
available and are described below.
 Sig CA Thin- Watery consistency, thin CA should only be used when the two parts to be joined are in perfect contact
with zero gap. Capilliary action pulls this glue deep into the wood resulting in a very strong bond and it dries in just a few
seconds. Thin CA can be used to tack assemblies together, but these joints should be glued again later with medium or
thick CA. Thin CA is also necessary for installing Easy Hinges.
 Sig CA Plus- Our medium thickness CA is excellent for almost any step during construction. The extra thickness allows
the glue to fill small gaps, but it does dry a little slower than a thin CA.
 Sig CA Slow- This thickest formula is good for filling large gaps and building up strong fillets at joints requiring extra
strength. It also dries slow enough to allow you to apply it to one part and position it on another before it dries. This
feature is useful when laminating large sheeted areas like a fuselage side and a fuselage doubler.
 Sig Kwik-Shot Accellerator- Spraying accellerator on CA (any thickness) will cure it almost instantly. Although CA is
fast, it's sometimes nice to speed it up even more.
 Debonder- This can be used to separate parts, but you'll probably use it for unsticking your fingers more than anything
else!

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CAUTION: Some people have experienced allergic reactions when exposed to epoxy
or cyanoacrylate glues. This is very rare. However, it is always important that such
glues, and also paints, thinners and solvents, be used with adequate ventilation to
carry fumes away.
YOU'LL NEED GOOD SANDING BLOCK
An assortment of different size sanding blocks are indispensable tools for model
construction. A good general purpose block can be made by wrapping a 9"x11"
sheet of sandpaper around a piece of hardwood or plywood. Use three screws
along one edge to hold the overlapped ends of the sandpaper. Put 80-grit paper
on the block during general construction. Switch to 220-grit paper for final finish
sanding just before covering.
In addition to the large block, there are places where a smaller one is handy.
Also, a sandpaper "file" can be made by gluing sandpaper to a flat spruce stick or
around a hardwood dowel for working in tight places.
NOTES BEFORE BEGINNING CONSTRUCTION
Any references to right or left refers to your right
or left as if you were seated in the cockpit.
To build good flying models , you need a good
straight building board. Crocked models don't fly
well! The building board can be a table, a
workbench, a reject "door core" from the lumber
yard, or whatever - as long as it is perfectly flat
and untwisted. Cover the top surface of the
building board with a piece of celotex-type wall
board or foam board, into which pins can be
easily pushed. Don't hesitate to use plenty of
pins during assembly to hold drying parts in
their correct position.
When pinning or gluing parts directly over the
full-size plans, cover the plan with wax paper or
plastic kitchen wrap to prevent gluing the parts
to the plans.
Don't use a ball point pen for making marks on
the model during construction. If not sanded off
these ink marks will show through the model's
final finish. Use a pencil instead of a pen.
Leave all the die-cut parts in the sheets until
needed for construction. Then remove pieces
from the sheets carefully. If difficulty is
encounted, do not force the part from the sheet.
Use a modeling knife to cut it free.
The die-cut balsa and plywood can be identified
using the plans and the "Key to Die-Cut Parts"
below. Mark the identification numbers on the corresponding parts before removing them from the die-cut sheets
All of the other parts can be identified by the "Complete Kit Parts List". Sort the different sizes of sticks and sheets into individual
piles to avoid confusion during building.

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ABOUT THE BUILDING SEQUENCE
The quickest and most efficient way to complete a model is to work on several pieces at the same time. While the glue is drying
on one section, you can start on or proceed with another part. Keep in mind that the number sequence used in these
instructions was chosen as the best way to explain the building of each major component and is not intended to be followed
exact one-two-three fashion. Start on the wing at No.1 and after doing as many steps as is convenient, flip over to "Fuselage
construction" an do a step or two or three, then back to "Wing Construction" and so forth. You will arrive at points where you can
go no farther until another component is available.
Plan ahead! Read the instructions completely and study the full size plans before beginning construction.
COMPLETE KIT PARTS LIST
Die-Cut Balsa
4 1/16"x3"x18" Wing Ribs 2 3/32"x4"x18" Fuselage Side,
Fuselage Doubler
1 1/8"x4"x18" fins, Wing Bloc
Pads (WBP)
Printed Balsa
1 1/4"x2"x12" Canopy, Wing Dowel
Supports (WDS)
Sheet Balsa
2 1/16"x1"x36" Trailing Edge
Sheeting
1 1/16"x3"x18" Wing Center
Sheeting
2 1/16"x3"x36" Leading Edge
Sheeting
1 1/8"x3"x18" Fuselage Bottom
2 1/8"x4"x10" Sheets for Optional
Fins
2 3/16"x4"x12" Stabilizer and
Elevator
2 1/4"x3"x3" Fuselage Top,
Cowl Bottom
Stick Balsa
3 1/16"x1/4"x36" Capstrips 1 1/4"x1/4"x36" Leading Edge 5 1/4" Traingle x12" Corner
Braces, S id Sides
1 1/2" Triangle x6" Cowl Filler
Block Balsa
2 1"x1-1/2"x9" Wingtips
Special Cut Balsa
1 3/16"x3/8"x36" Tapered Trailing
Edge
2 3/16"x1-1/4"x12" Tapered Ailerons 4 3/16"x1"x3" Cowl Sides
Pre-Cut Plywood
1 3/32"x2-3/4"x6" Birch Ply F-1,
Aileron Servo Mounts (ASM)
1 1/8"x2-3/4"x9" Lite-Ply Formers,
HP, Hatch Lip, Spinner Ring
Sawn Plywood
1 1/16"x7/8"x2-1/2" Birch Ply Wing
Hold-Down Plate
Hardwood
1 1/8"x1/8"x9" Spruce Fin Stiffener 2 1/8"x1/4"x36" Spruce Wing Spars 1 1/8"x5/16"x12" Spruce S id 2 3/16" dia. x1-1/2" Birch Wing
Dowels
2 1/4"x1/2"x1-1/2" Basswood Wing
Hold-Down Bloc s
Formed Wire Parts
1 4-40x8" L.H. Aileron Torque Rod
(with brass bearing)
1 4-40x8" R.H. Aileron Torque Rod
(with brass bearing)
Miscellaneous
1 4"x20" Decal DKM-266A (for
Standard Version)
1 4"x20" Decal DKM-266B (for
Russian Version)
1 4"x20" Decal DKM-266C (for
Angel Version)
1 4"x20" Decal DKM-266D (for
Patriot Version)
1 38"x50" Full-Size Printed Plan 1
20 pg. Photo Illustrated Instruction
Boo
Hardware
2 Small Glass-Filled Engine Mounts 2 #2x3/8" Flat Head Wood Screws
(for hatch)
2 #2x1/2" Sheet Metal Screws
(for control horn)
4 6-32x5/8" Soc et Head Mounting
Bloc s (for engine mounts)
2 10-32x1" Nylon Wing Bolts 4 6-32 Blind Nuts (for engine
mounts)
1 2-56 Solder Lin (for
throttle)
3 2-56 Nylon RC Lin s (2/aileron,
1/elevator)
3 2-56x10" Threaded Rods
(2/aileron, 1/elevator)
2 4-40 Nylon Aileron Connectors 1 Nylon Control Horn (for
elevator)
1 130" o.d.x12" Nylon Tubing (for
throttle pushrod)
1 1/16" dia.x12" Steel Cable (for
throttle pushrod)
7 3/4"x1" Easy Hinges 1 Pushrod Connector Pac age

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WING CONSTRUCTION
The Wonder wing is designed to be built in one piece, flat on the building board (no dihedral or washout). Pin or tape the wing
plan to your building board and protect the plan by covering it with wax paper or plastic wrap.
1.
a. Pin the 1/8"x1/4"x36" spruce lower wing spar over the plans. Instead of pushing pins right through the spruce (which
could cause it to split), cross two pins over the spar to hold it in place.
b. Glue the 16 die-cut balsa wing ribs to the lower wing spar. Each wing rib should be vertical and the alignment tab at
the trailing edge should be pinned firmly to the building board.
2.
a. Glue the 1/8"x1/4"x36" spruce upper wing spar to the wing ribs.
b. Find the 3/16"x3/8"x36" special-cut balsa trailing edge. By looking at its ends you will see that it is not symmetrical.
Rather, it is a 3/16"x3/8" balsa stick that has been tapered on its top surface from 3/16" at the front to 1/6" at the
rear. For the best fit, make sure the trailing edge is positioned properly in the wing rib notches as shown in the
diagram. Glue the trailing edge to the wing ribs being careful not to glue the trailing edge to the alignment tabs.
c.
Add the 1/4"sq.x36" balsa leading edge to the front of the ribs.
3. The leading edge sheeting must be cut to its correct 2-3/4" width from the
1/16"x3"x36" sheets provided in the kit. Use a long straightedge and a sharp
modelling knife to trim the sheets. To help make the sheeting fit against the
leading edge, hold the knife at a 15 or 20 degree angle while cutting the front
edge of the sheeting, as shown in the photo.
4. Glue the leading edge sheeting to the leading edge using a bottle of thin CA with
a long applicator tube. Apply slow CA to the tops of the wing ribs and the upper
spar, then push the sheeting into place with your hands. You may have to use
accelerator spray on small sections at a time until the sheeting is completely
glued in place.
NOTE: Harder sheeting may need to be wetted before bending it into place, to prevent cracking. Warm water sponged onto
the outer surface will cause the sheeting to swell, allowing it to conform easily to the rib contour.
WONDER WHY...
...we don't just give you 2-3/4" sheeting in the kit?
Answer:
Internal stresses can cause a sheet of balsa to bow, even when cut from a
perfectly straight plank. Experienced modelers know that the only way to
ensure a straight sheet of balsa is to cut the edges themselves, just before
gluing it in place on the model. Trimming the edges is an easy step that will
help you build a true wing.
5.
a. Add the 1/16"x1"x36" balsa trailing edge sheeting.
b. Sheet the upper center section of the wing using pieces cut from the 1/16"x3"x18" balsa provided in the kit. Sig-
Bond
(yellow wood glue) is recommended for the edges of the sheeting because it's easier to sand than CA.
c.
Glue the 1/16"x1/4" balsa capstrips to the upper edge of the remaining wing ribs and allow to dry.

.
6.
Unpin the wing from the building board. Carefully cut away the alignment tabs on all of the wing ribs.
7.
a. Use a jigsaw or a sharp modeling knife to cut the two wing dowel supports (WDS) from the 1/4" printed balsa sheet.
Saw just outside the lines, then true up the edges with a sanding block, leaving the complete black line on the parts.
b.
Glue the wing dowel supports to the two center ribs as shown on the plans.
8.
a. Turn the wing over and pin it to your building board. The wing is now rightside up. Mark the top of the wing for
identification in latter steps. Use a piece of scrap stick wood to support the trailing edge. It's very important to keep
the support stick straight and aligned with the trailing edge - you don't want to build in any warps now. Pin the
support stick to the board and pin the wing to the support stick to hold everything firmly in place.
b. Glue on the bottom leading edge sheeting, the bottom trailing edge sheeting, and the bottom capstrips. Hold off on
the bottom center sheeting; it will be installed later.
9. When dry, unpin the wing from the building board. If you have been using thin or
medium CA glue during construction, now is the time to go back over every joint
with medium or thick CA. Don't be stingy here
- the integrity of your wing depends
upon strong glue joints. Glue each side of each joint. A long aplicator tube will
help you reach inside the leading edge sheeting.
10. Now you can glue on the 1/16" balsa bottom center sheeting.
11.
a. Carve and sand the wing leading edge to shape. For best stall
characteristics, you want a nicely rounded leading edge as shown on the
plans. Use a long sanding block to make certain the curvature is consistent
along the entire length of the wing.
b. If necessary, touch up the trailing edge with a sanding block so that it's flat
and straight.
c.
Cut off and sand the spars, leading edge, trailing edge and sheeting at both
ends of the wing flush with the end ribs
d. Give the wing a final sanding over it's entire surface with a long sanding
block. Sand just enough to remove any prominent high spots or bumps. Be
careful! Excessive sanding may disturb the airfoil shape.
12. Decide now which type of wingtip you plan to use, then cut or trace the top view of the wingtip from the plan. Transfer the
shape of the wingtip to the tops of the 1"x1-1/2"x9" balsa block wingtips using the paper outline as a guide. Rough cut the
blocks to shape with a bandsaw or a jigsaw.
13.
a.
Glue the wingtips to the end ribs. If one of the blocks happens to be heavier than the other, glue the heavy one to the
left end of the wing to help offset the weight of the engine's muffler, which is generally on the right side. Sig-Bond is
again recommended for easy sanding.
b. When dry, carve and sand the wingtips to shape. If you are building the "Standard" Wonder, see the separate
instructions for "Carving Vortex Wingtips". If you are building another version, start by carving and sanding the blocks
to match the airfoil contour, then round off the corners.
c.
Reinforce the thin trailing edge of each wingtip by soaking it with several drops of thin CA.

.
14. Locate the 1/16"x7/8"x2-1/2" plywood
wing hold
-down plate, then round off the
top edges and the corners with a
sanding block. Glue the wing hold-down
plate to the top of the wing so that it's
centered left to right and overhangs the
trailing edge 3/16".
Carving Vortex Wingtips
The down-turned vortex wingtips used on the Standard version of the Wonder
were chosen more for their looks than any kind of aerodynamic reason.
Theoretically this type of wingtip is very efficient, but on a model of this size it
really makes little difference.
They are easier to carve and sand than
they appear, so give 'em a try!
1. Cut out the top view of the wing tips
(see step 12 above). Draw a line on the
inside surface of each tip, 11/16" from
the bottom.
2. Glue the wingtip to the end rib so
that it's flush with the bottom of the
airfoil and the drawn line passes
through the exact center of the trailing
edge. When dry, us the WT wingtip
plate (cut from plans) to mark the
shape of the trailing edge on each
wingtip.
3. Carve and sand the wingtip blocks to
match the contour of the entire upper
surface and back to the spar on the
lower surface.
4. Rough carve the concave portion of
the tips using an X-Acto #162 router
blade.
5. Finish sand the concave portion with
a large dowel wrapped with 80-grit
sandpaper.
6. The rest of the block can now be
carved and sanded pretty much like a
normal, rounded wingtip. Be sure to
strengthen the trailing edge area of
each wingtip by soaking then with thin
CA. Smooth things up with a hand-held
piece of 150-grit sandpaper.
WONDER WHY...
...there's no dihedral brace or
sheer webs in the wing?
Answer:
All of the spars and sheeting in the
Wonder wing run the full span of the
wing, from tip to tip. Since there is
no center wing joint, there's no need
for a dihedral brace or reinforcing
fiberglass tape. The center sheeting
is more than adequate to absorb the
aerodynamic loads at the center of
the wing.
None of the Wonder prototypes ever
used, or needed, shear webbing.
The low-aspect-ratio, 15%-thick
wing simply doesn't need the extra
strength or weight of shear webs,
and you don't need the extra work of
installing them!
15.
a.
Draw a line on the trailing edge at
the exact center of the wing, then
two more lines spaced 1/2" on
either side of the center. The
second two lines indicate where
to position the inner end of the
torque rod brass bearings, which
should now be glued in place.
Make certain the torque rod
assemblies are centered vertically
on the wing trailing edge and be
careful not to get any glue in the
bearings.
b. When dry, fill the small gaps
above and below the torque rods
with more glue or balsa filler and
sand it smooth.
c.
Cut clearance notches in the wing
trailing edge for the inner end of
the torque rods.

.
16. a. Two pieces of 3/16"x1-1/4"x12" tapered balsa are provided for making the
ailerons. Choose an aileron pattern, cut it from the plans, trace the outline
onto both pieces of tapered balsa, then cut the ailerons to shape.
b. Carefully block sand the top and bottom surface of each aileron equally so
that the leading edge remains 3/16" thick and the trailing edge is a constant
1/16" or less. You'll need to steepen the angle of the sanding block as you
approach the aileron tip to make the trailing edge a constant thickness. This
sounds tricky, but it won't take more than a few passes of an 80-
grit sanding
block.
17.
a. Draw a hinge line centered on the leading edge of each aileron. Use a
sanding block to bevel the front of the ailerons using the hinge line as a
guide.
b. Position the ailerons on the back of the wing, leaving a 1/32" gap between
the ends of the aileron and the wingtips. Mark the locations for the torque
rods, then slot and drill the ailerons to receive the torque rod wires.
18. Trial fit the ailerons to the torque rods.
Once they fit, temporarily tape the
ailerons in place and sand the wingtips
and ailerons in place and sand the
wingtips and ailerons as necessary to
blend smoothly together.
FUSELAGE CONSTRUCTION
Basic Fuselage Assembly
19.
a. Glue together the two die-cut 3/32" plywood F-1 pieces using Kwik-Set
epoxy or slow CA. Use a heavy weight of some kind to hold the two pieces
perfectly flat while drying.
b. Mark the vertical centerline and thrust line on the F-1 assembly using the
cross-section on the plan as a guide.
c. Determine the spacing that will be necessary between the two glass-filled
engine mounts to fit your engine, then position the mounts on F-1
accordingly. Mark the location of the four mounting holes and drill them out
with a 3/16" drill bit.
20. Lightly hammer four 6-32 blind nuts into the back of F-1. Bolt the engine mounts to the front of F-1, using 6-32x5/8" socket-
head bolts to align the blind nuts (see note below). Apply medium or slow CA around the edges of the blind nuts to hold
them in place.
NOTE: The shank of the 6-32 blind nuts may extend too far through F-
1 and interfere with the back of the engine mounts. To
avoid any interference, drill a 3/16" dia. relief partially through the back of the mounts at each hole.
21.
a. Position your engine on the
mounts so that the rear face of the
spinner backplate is between 2-
3/4" and 3" from F-
1. Mark through
the engine mounting holes with a
pencil, then remove the mounts
from F-1.
b. Drill and tap the mounts for the
engine bolts (not included).

.
22. Re-install the engine mounts, bolt the engine in place, then install the pushrod connector (included in your kit) on your
engine's carburettor control arm. Locate and mark the best spot on the firewall for the throttle pushrod to exit and line up
with the pushrod connector. Now you can remove the engine and mounts, and drill at the mark with a 9/64" drill bit.
23.
a. Hold the two 3/32" die-cut balsa fuselage sides together and sand the edges lightly until they are a perfect match.
b. Mark the positions of the three formers on the fuselage-sides. Marking the right-hand fuselage side is easy. Place it
over the "Typical Radio and Engine Installation" drawing on the plan and use the small guidelines to mark the balsa.
Now you can use the right-hand fuselage side to transfer identical markings to the inner surface of the left-hand
fuselage sides.
24.
a. Glue the 3/32" die-cut balsa fuselage doublers to the fuselage sides.
b. Glue a piece of 1/4" balsa triangle along the bottom of each fuselage side. Notice that the aft end of the triangle
piece should end at the rear face of former F-4.
c. Tack glue the 1/8" die-cut lite-ply formers F-3 and F-4 in place on one of the fuselage sides using a triangle to make
certain they are square with the side.
25. While holding the second fuselage side in place on the formers, check the alignment of the fuselage over the top view on
the plan. When satisfied, glue both fuselage sides firmly to F
-
3 and F
-
4.
26.
a. Tape former F-1 in place on the front of the fuselage, and again check the alignment over the top view on the plans.
Notice that the correct amount of downthrust (4 deg.) is built in automatically by lining up the front face of F-1 with
the front edge of the fuselage sides. There should be no side thrust when viewed from above. When satisfied, glue
F-1 to the fuselage sides from the front and back with thin CA.
b. Trim the 1/4" triangle stock flush with the front of F-1.
c. Cut two braces for F-
1 from 1/4" balsa triangle stock and notch them as necessary to clear the blind nuts on the back
of F-1. Apply slow CA to the braces and press them firmly in place.
d.
It may be necessary to redrill the hole for the throttle pushrod through a triangle brace that was installed. Use a 9/64"
drill bit.
27. Carefully position a straightedge so that it's lined up with the rear face of F-4 on the outside of the fuselage. Use a sharp
knife to cut through about half the thickness of each fuselage side. Now the back end of the fuselage can be literally
"cracked" into position. If it happens to snap off completely, that's okay; it can be re
-
attached in the next step.
28.
Firmly pin the fuselage upside down over the top view on the plan so that it can't move. Now you can hit the cracked joint on
each side with a bit of CA to hold the rear fuselage in alignment.

.
29. Cut the 1/8"x3"x18" balsa fuselage
bottom into four pieces as shown in the
diagram. With the fuselage still pinned to
the plan, glue on the bottom pieces in the
order shown. Notice the grain direction of
each piece, and be sure to just tack glue
to the hatch - it will be removed later.
WONDER WHY...
...there's a hatch way be there?
Answer:
If you've looked ahead in these
instructions or at the plans, you have
already seen that a servo will probably
have to be located in this area and
possibly the battery and switch too.
30. Remove the fuselage from the building board and fill the scored areas on the fuselage sides with medium or slow CA. Trim
and sand all of the bottom pieces flush with the fuselage sides. Use a long sanding block to round off the bottom corners of
the fuselage aft of F
-
4.
31.
a. Remove the hatch and glue in two die-cut 1/8" lite-ply hatch plates (HP).
b. Slide the die-cut 1/8" lite-ply hatch lip (HL) into place on the fuselage bottom. Put a drop or two of slow CA on the
exposed part of the hatch lip, then put the balsa hatch back into place. The idea here is to glue the hatch lip only to
the balsa hatch.
32.
a. With the hatch still in place, use the plans as a guide to carefully mark the location of the two hold-down screws. Drill
completely through the hatch and the hatch plates at the marks with a 1/16" drill bit.
b. Remove the hatch, then redrill the hatch holes with a 3/32" drill bit. The holes can be countersunk for the flat-head
wood screws using a sharp 1/4" drill bit. Strengthen the countersunk area with a few drops of thin CA.
c.
Re
-
glue the hatch lip firmly to the hatch.
33.
a. Carefully drill at the two dimples in F-2 with a 1/8" drill bit, followed by a
3/16" drill bit. Use a chunk of hardwood behind the former to keep the wood
from splintering as you drill through.
b. Glue F-2 into position as shown on the plans.
Mounting the Wing to the Fuselage
NOTE: The wing must be finished through step 14 before proceeding.
34. Position the wing on the fuselage and check its alignment as shown in the
diagram. When staisfied, firmly tape and pin the wing in place.
35. Drill two holes into the wing for the wing dowels. The easiest way to do this is to run a long 3/16" drill bit along the top edge
of F-1, through the holes in F-2, and into the wing. If you don't have a long drill bit, you can turn a shorter one by hand to get
the holes started then finish off the holes after removing the wing.

.
36. a. Remove the wing and insert the two 3/16"dia.x1-1/2" wing dowels into F-2
from the aft side so that they extend in front of F-2 about 1/16". Slide the
wing into place to check that it seats properly on the fuselage. If not,
slowly enlarge the holes in the wing until it does seat properly. Again
remove the wing, leaving the dowels in place in F-2.
b. Apply several drops of Kwik-Set epoxy to the holes in the wing. Slide the
wing back into its proper position on the fuselage until the epoxy is dry. Be
careful not to glue the wing dowels to F-
2. When dry, remove the wing and
fill any gaps around the dowels with another application glue.
37.
a. Glue the two 1/4"x1/2"x1-1/2"
basswood wing hold-down
blocks into the notches in the
fuselage doublers.
b. Add the die-cut 1/8" balsa wing
block pads (WBP) to the top of
the basswood blocks.
c. Carefully sand the balsa wing
block pads to match the contour
of the wing saddle area.
38.
a. Fit the wing in place on the fuselage and check its alignment one last time. When you are satisfied that it's aligned
correctly, tape or pin the wing so that it can't move.
b. Carefully mark the drill locations for the wing bolts using the plan as a guide. Drill through the wing and the wing
hold-down blocks at the same time with a 5/32"dia. drill bit. Keep the drill perpendicular to the top surface of the
wing so the heads of the nylon bolts will seat flush against the plywood plate.
39.
a. Remove the wing and tap the
wing hold-down blocks with a 10-
32 tap. You can apply a few
drops of thin CA to the holes to
strengthen the threads.
b. Redrill the holes in the wing with
a 3/16" drill bit to pass the nylon
wing bolts.
Finishing The Fuselage
40. Now is a good time to prepare your fuel tank for installation. The 4oz slant tank
from Sullivan (not included) fits well and should sit as high in the fuselage as
possible. The fuel lines from this tank exit the fuselage at the joint between F-1
and the balsa top. You can prepare F-1 for the fuel lines by sanding or filing semi-
circles into the top edge. If you plan on using a different type of fuel tank, drill
holes in F-1 as necessary for the routing of the lines.
41.
a. The 1/4"x3"x3" balsa fuselage top can be shaped at the aft end to match
the contour of the wing leading edge. Glue the fuselage top in place so
that the aft end fits snugly against the wing.
b. Trim and sand the fuselage top flush with the sides and F-
1, then round off
the side corners with a sanding block.
c. Finish drilling the fuel line holes through the balsa.

.
42.
a. The balsa cowl is made of several parts that are basically built up around the engine. Install the engine mounts and
your engine with the spinner that you intend to use. Cover any openings in the engine (carb, exhaust) with tape to
protect it from dust.
b. Begin the cowl construction by gluing the 1/4"x3"x3" balsa cowl bottom to the front of F-1 so that it's flush with the
fuselage bottom. Sig-Bond is recommended for all of the cowl parts because it will be easier to sand later.
c. Add two of the 3/16" pre-
cut balsa cowl sides leaving about 1/16" between them and the engine mounts. Depending
on the width of your engine, the cowl sides may or may not blend into the spinner backplate. If not, cut off the front
end of the two remaining cowl sides and glue them in front of the engine mounts.
43. Remove the engine and the mounts,
then fill the bottom inside corners of the
cowling with pieces of 1/2" or 1/4" balsa
triangular stock. Taper the triangular
stock towards the rear so it doesn't
interfere with the engine mounts.
44. Bolt the engine back in place and
carefully sand the front edge of the cowl
with a narrow sanding stick. Sand until
the gap between the cowl and the
spinner backplate is about 5/32".
WONDER WHY...
...the Wonder cowl is made of balsa instead of plastic?
Answer: Flexibility. The Wonder uses lots of different engines which all have
different lengths, which all require something of a custom cowl. Besides, a
balsa cowl allows you to cover the fuselage right up to the spinner ring with no
seams. Actually, you can leave the cowl off with no adverse effects on flight
performance - it just won't look as good!
45.
a. Glue the die-cut 1/8" lite-ply spinner ring to the front of the cowl, making
certain it is aligned with the spinner backplate. Notice that the spinner ring
is cut oversize to allow for a bit of sanding.
b. Prepare the spinner backplate for the cowl sanding process by protecting
the edge with tape.
c. Carve and sand the cowl to blend in smoothly with the spinner at the front
and the fuselage at the rear. Now's a good time to round off the bottom
corners of the fuselage (forward of F-
4) as well. Do the rough sanding with
80-grit sandpaper, then smooth it down with some 150-grit.
46. The landing skid is constructed by
gluing two 1/2" lengths of 1/4" balsa
triangle stock to the sides of the
1/8"x5/16"x12" spruce skid. Sand the
spruce round on the bottom and shape
the ends as shown on the plans.
WONDER WHY...
...there's no landing gear on this design?
Answer: Well, let's look at the pros and cons of going with a skid instead of wheels on the Wonder. On the positive
side, without landing gear the Wonder is lighter, simpler, costs less, flies faster, performs better, and simply looks
sleeker. The negative is you can't land on concrete (technically you can, but it's certainly not recommended!). Even if
it had wheels, the Wonder would still require a hand launch because there's no ground steering without a rudder. So
find a field and have at it!
.

TAIL SURFACES
47.
a. Make the stabilizer by edge gluing two 3/16"x4"x12" balsa sheets (Sig-Bond is recommended). When dry, block
sand the joint until it's smooth.
b. The stabilizer must be accurately cut to it's proper width of 11-
1/4". Start by drawing a centerline and two edge lines,
each spaced 5-5/8" from the centerline. If you don't have an accurate 90 deg. square, you can use the plans as a
guide. Use a sharp knife to make the cuts on each edge.
48.
Cut the elevator from the stabilizer using the elevator shape of your choice. Bevel
the leading edge of the elevator, sand the trailing edge round, and trim each tip
about 1/16" to clear the fins.
49.
If you are building the Russian, the Angel, or the Patriot, you need to hand cut the
fins from the two sheets of 1/8"x4"x10" balsa. Edge glue the sheets, then cut the
fins out using the pattern of your choice. Add the 1/8" sq. spruce stiffeners, sand
the sides smooth, and round all the edges.
50.
a. To make the two fins for the
Standard version, simply glue
together the die-
cut 1/8" balsa fin
pieces together as shown on the
plan.
b. Add a piece of 1/8" sq. spruce to
the bottom of each fin to act as a
stiffener. When dry, sand the fins
smooth on each side and round
all of the edges.

.
COVERING
General Instructions
All of the Wonder prototypes were covered with Sig Supercoat Iron
-On Plastic Covering. Supercoat is ideal for sport
models because it's lightweight and easy to apply. One roll is plenty for a Wonder, but most modelers will want two or
more colors.
Details about colors and decal placement for specific versions of the Wonder follow. All four versions have different colors
or markings to help distinguish the top of the model from the bottom. This is very important for visibility in flight, especially
with small, fast models like the Wonder. Keep this in mind if you plan your own custom color scheme.
We recommend that you cover the wing, fuselage, tail surfaces, control surfaces, and skid all separately before hinging
and final assembly. This way the parts are much easier to handle.
The following instructions provide advice and procedures specific to the Wonder. Be sure to read the two pages of step-
by-step, photo illustrated instructions included with each roll of Supercoat. If you choose another brand of covering
material, be sure to read the manufacturer's directions (supplied with the covering) and follow them carefully.
Surface Preparation
A good covering job starts with a good surface preparation. Regardless of what type of covering you choose, it won't hide
poor workmanship. Fill any small surface gaps or dents with a lightweight filler or spackling paste. Sand the entire model
with 220
-grit sandpaper, then again with 360 or 400-grit sandpaper.
Since it's too difficult to apply covering material to F-1 and the inside of the cowl, they must be fuel-proofed using several
coats of clear dope or two coats of polyester (glass) resin, sanded between coats. Finish off the engine area with a few
coats of colored Sig Supercoat Dope. (Most of the Sig Supercoat Plastic Covering colors have a matching Sig Supcoat
Dope color.)
Covering The Fuselage
The fuselage should be covered with four pieces of material, starting with the bottom, followed by the two sides, and
ending with the top. If you're using more than one color, it may take more pieces of material. All seams should overlap
about 1/8". When covering solid wood surfaces like the fuselage sides, better results can be obtained by starting at the
center and working toward the outer edges, allowing air to escape as you iron.
Experienced modelers know that oily engine exhaust likes to creep into every crack it can find, which means special care
must be taken to keep the hatch area as fuel-proof as possible. When you cover the hatch, be sure to cover the front and
rear edges, and wrap the material around both sides about 1/4". The covering material on the fuselage sides should wrap
around the bottom in the hatch area as well as the wing saddle area.
Covering The Wing
Begin the wing by covering the wingtips and plywood hold down plate. Cover each wingtip with two pieces of material, first
the bottom and then the top. Seal each piece securely to the capstrip and sheeting for the end rib. Later, when the main
top and bottom covering pieces are applied, they will overlap the wingtip covering on the end rib. Cover the hold-down
plate with a single piece of material, extending it about 1/8" past the outside edges of the plate to provide an area for
overlap. Cover the main portion of the wing starting with the bottom and then the top so that the seams will be on the
bottom where they will be less visible. The top covering should overlap the full width of the leading edge and trailing edge.
Wait until both the top and bottom pieces of covering material have been sealed completely around the edges before
shrinking the large open areas between the ribs. Alternate between the top and bottom surface to avoid uneven shrinking
which could cause warp. Your sealing iron or a special heat gun can be used (household blow dryers don't provide enough
heat). Keep the heat gun moving at all times or you may burn a hole in the covering. If you notice the covering material
"ballooning up", put a small pin hole in the bottom of each rib bay to allow the expending air to escape.
Covering The Sheet Balsa Parts
The stabilizer, elevator, fins, ailerons, and canopy pieces should each be covered with two pieces of material -
bottom first,
then top. Iron the material from the center out to avoid trapping air bubbles.
Don't be alarmed if these small parts bow slightly after covering just one side. This is a common condition that should
correct itself after covering the second side.

.
Applying The Decals
Cut out the decals with sharp scissors, leaving about 1/32" to 1/16" of clear at all edges and rounding the corners as you
cut. Wet the surface on which the decal will be placed with soapy water (use dishwashing detergent). Place the decal on
the model and squeegee the water from underneath with a balsa paddle. This procedure allows time for repositioning and
prevents air from being trapped under the decal. Allow several hours to dry.
INSTALLING EASY HINGES
Sig's famous Easy Hinges have been included with your kit to hinge all of the
control surfaces. Each ultra-thin hinge is actually a three-part laminate - a tough
plastic inner core sandwiched by an absorbant wicking material. They have been
chemically treated to slow down the reaction of thin CA (which is normally
instant), to allow the glue time to soak all the way to the ends of the hinge and
into the wood surrounding it. Once the glue has dried, the hinge cannot be pulled
from the structure without tearing the wood out with it! We recommend that all
surfaces be covered before hinging.
51. Using a No.11 X-
Acto blade (or similar), cut slots approximately 1/2" in depth and
slightly wider than the hinges. Cut three slots in the stabilizer and three matching
slots in the elevators at the locations shown on the plans.
52.
After all of the slots have been cut, insert Easy Hinges halfway into the stabilizer
slots. Do not glue the hinges yet! Next, carefully slide the elevator onto the
hinges. You'll find it easiest to slide the elevator onto the hinges at an angle, one
at a time, instead of trying to push it straight onto all of the hinges at once. Don't
be concerned if the hinges aren't perfectly straight or centered in the slots -
they'll
work fine regardless of their final position.
53.
a.
To set the hinge gap, deflect the elevator to the maximum amount needed.
For best control response, the gap should be as small as possible but big
enough to allow full movement of the control surface without binding.
b.
Easy Hinges were designed to use Thin CA (any brand) for maximum glue
penetration. Place three or four large drops of thin CA directly onto the
hinges in the gap. The glue will wick into the slot as it penetrates both the
wood and the hinge. Continue this process, gluing the same side of all the
hinges, then turn the stabilizer over and repeat the gluing process on the
other side of each hinge.
54.
After the glue has cured (3 to 5 minutes) the joint should be flexed to full deflection in each direction a couple of dozen
times to reduce the stiffness. Don't worry about shortening the life of the hinges as they are almost indestructible.
55.
a. The ailerons are hinged like the elevator, but the torque rods must be glued as well. Start by cutting the slots in the
wing and the ailerons (two per aileron) and slide the hinges into the ailerons.
b. Slide a small piece of wax paper between the torque rods and the wing. Working with one aileron at a time, apply
Kwik-Set epoxy to the slot and hole in the aileron leading edge and slide it onto the torque rod, working the Easy
Hinges into the wing slots at the same time. Before the glue sets, be sure to deflect the aileron back and forth to set
the proper hinge gap.
c.
Once the epoxy has cured, remove the wax paper and apply thin CA to the hinges as you did earlier.
FINAL ASSEMBLY
56. Use a sharp knife to carefully cut away the covering material on the fins where thry contact the stabilizer. Glue the fins to
the stabilizer using a triangle to check their alignment.

.
57. a. With the wing bolted in place on the fuselage, trial fit the stabilizer/fin assembly. The stabilizer should sit against the
back of the wing with no gap. If the stabilizer seems tilted slightly, you should trim the top of one of the fuselage
sides until the stabilizer sits level with the wing.
b. When satisfied with the alignment, draw cut lines on the bottom of the stabilizer at the fuselage sides. Remove the
stabilizer and use a sharp knife to cut away the covering on the bottom where it will be glued to the fuselage.
58.
a. Hold the stabilizer/fin assembly in place on the fuselage, then glue it firmly with CA working through the hatch
opening.
b. Install the nylon control horn on the elevator so that it's centered in the opening at the back of the fuselage. Use two
#2x1/2" sheet metal screws to install the horn, then clip or grind off the pointy ends of the screws.
59. Cut out the canopy of your choice from the printed 1/4" balsa sheet, again leaving the entire black line on the parts. Match
the bottom edge of the canopy to your wing by taping sandpaper to the wing's upper surface and gently pushing the canopy
from side to side.
60. If you chose the one-piece Angel canopy, go ahead and round off the upper edge, cover it, and glue it to the top of the wing
(after removing a strip of covering material to provide a wood-to-
wood joint, of course). The other Wonder versions feature a
two-piece canopy with the front portion glued to the wing and the rear portion glued to the stabilizer. Temporarily pin the
canopy parts in their proper position on the assembled model, then attach the front and rear canopy parts to each other with
a piece of tape on each side. Now the canopy parts can be lifted from the model and their top edges sanded round at the
same time so they will match perfectly when installed. Remove the tape, cover the canopy parts, and glue them in place.
61. Install your fuel tank, engine and muffler. The easiest way to install the fuel tank (which was prepared in step 40) is to run
extra-long fuel lines through F-1, attach them to the tank, then slide the tank into place while gently pulling the fuel lines
back through F-1. Now you can bolt your engine mounts to F-1, bolt your engine to the mounts, bolt the muffler to your
engine, and cut the fuel lines to their final length. The propeller should be mounted so that it's level with the wing when it
comes up against the engine compression, to minimize the chance of breaking it during landings. Attach your spinner cone
and the engine installation is complete.
62. Glue the skid to the bottom of the fuselage.
RADIO INSTALLATION
Different radio installations using different size servos and receivers are described under specific versions of the Wonder
following. One thing that's common to all of them is that they're stuffed into one tight little fuselage! Every radio installation is
unique and must be planned carefully to make certain that the servo arms and control linkages have clear room to operate.
The following guidelines are meant to provide general information on stuffing a Wonder with radio gear.

.
Start your radio installation with the receiver. All of our prototypes had the receiver installed just behind the fuel tank in the
opening in F-3. Wrap the receiver in 1/4" foam rubber for protection.
With the receiver in place, now you can install the aileron servo. Measure carefully for the cutout in the wing so that the
aileron servo will clear the receiver. Glue the two die-cut 3/32" plywood aileron servo mounts (ASM) to the balsa sheeting,
and screw the servo in place. Make the aileron pushrods from threaded rod and nylon clevises then hook them up to the
nylon aileron connectors (which should be threaded onto the torque rods). You can use an extension wire from the
receiver to the servo, but we typically plug the aileron servo wire directly into the receiver just before bolting on the wing.
This saves weight and keeps loose wires to a minimum. You may have to make a small notch in the stabilizer leading
edge to clear the torque rods during wing installation.
Now you need to do some decision making. The battery, switch, and remaining servos should be positioned as necessary
to achieve the proper balance point on the finished model without having to add weight to the nose or tail. If you're using a
very lightweight engine, the battery will probably need to go under the fuel tank and receiver. Heavier engines will dictate a
more rearward battery position, possibly behind F-4. Assemble the Wonder , place it on a balancing stand, then shift the
components around on the outside of the model until you find the best arrangement.
BALANCING
IMPORTANT: It is vitally important that your Wonder is balanced properly. The correct balance point for first flights is 2-
3/8" (plus or minus 1/16") behind the wing leading edge. This is a short-coupled airplane and the balance range is very
small. Our prototypes all flew well with the balance point between 2-5/16" and 2-7/16" behind the leading edge. If the
balance point is too far forward, the Wonder flies well under power but you can run out of "up" elevator during the
landing flare. If the balance is too far back, the plane can become unstable and eventually, uncontrollable.
Oh, and don't use your fingertips for balancing! Build yourself a quick and
dirty balancing stand like the one shown in the diagram. Mark the balance
point on the bottom of the wing with tiny lengths of striping tape. Shift the
radio gear or add weight as necessary to bring the balance point into the
proper range. Trying to fly with the balance point too far forward or too far aft
is much more dangerous than the slight increase in wing loading caused by
adding nose or tail weight. Always balance the model with an empty fuel tank
so that it sits level on the balancing stand.
In addition to the fore/aft balance, it's important that you balance the model
spanwise. A "heavy wing" on one side can result in poor loop tracking. To
check for this, pick up the assembled model by the spinner at the front and
under the center of the stabilizer at the rear. Insert weight (small finishing
nails work well) into the lighter wingtip until the model is balanced.
The battery should be wrapped in foam rubber and secured inside the fuselage with balsa sticks to keep it from moving.
The sticks can be broken away later when you need to remove the battery from the plane.
The throttle servo and the elevator servo on most of our prototypes were installed using servo tape, which works very well
on a small model like the Wonder. Here are a few tips for using servo tape:
 Coat the area of the fuselage where you plan to install the servo with glue, either epoxy or CA, and allow it to dry.
The tape will stick much better to this than it will to bare balsa.
 Clean the servo with alchohol before applying the tape.
 Cover the entire side of the servo with tape. You want as much bonding as possible.
 Make certain the servo arm and screw are installed before taping the the throttle servo in position. You won't be
able to get at the screw once the servo is taped in place!
The throttle pushrod is a 1/16" steel cable which moves inside a nylon tube. The hole in F-1 has already been drilled for
the tubing, but you need another hole in F-3 to route the tubing so that it's pointed directly at the servo arm. Solder the
clevis (included
in the kit) to the steel cable, route the cable through the nylon tube and into the pushrod connector located
on the engine's throttle control arm. Snap the solder clevis on the servo arm and adjust the cable at the pushrod connector
end.
The elevator servo is very easy to install through the hatch. Bend a pushrod to suit from a 2-56 threaded rod. At the field,
adjustments to the clevis can be made at the rear fuselage opening, if necessary.

.
The switch should be mounted on the fuselage side opposite the engine exhaust and where it can't be accidentally
bumped during launch. High in the fuselage behind F-4 works well. Route the antenna through the inside of the fuselage,
away from all the other wires, and out the rear opening. On very short models like the Wonder, all you can do is let the
excess antenna wire dangle behind the airplane. Under no circumstances should the antenna be shortened, folded or
bundled.
PRE
-
FLIGHT CHECKOUT
Range check your radio equipment according to the manufacturer's instructions before attempting test flights. A lot of
problems can also be avoided if your engine has been well broken in and the idle adjustment perfected on a test block or
in another airplane before installation in the new model.
Adjust all of your pushrod linkages so that the control surfaces are in their neutral position when the transmitter sticks and
trim levers are centered. The control surface movements listed below are recommended for the first flight of your Wonder.
These movements will provide the model with a fair degree of aerobatic capability if it's balanced correctly. Test flights may
indicate a need for slightly more or less movement, depending on individual model performance and personal preference.
RECOMMENDED CONTROL SURFACE MOVEMENTS
For test flying, the following are suggested:
ELEVATOR 1/4" UP and 1/4" DOWN
AILERONS 5/16" UP and 5/16" DOWN
Measured at the widest point of each control surface
"STANDARD" VERSION
The Standard Wonder is probably the
most generic-looking version, but it was
the original. All of the other versions
were an offshoot of the Standard. Its
most distinctive feature has to be the
down-turned vortex wingtips. The
wingtips probably don't do much
aerodynamically for a model of this size,
but they do look good and generate lots
of comments from fellow modelers.
Covering the "Standard"
The Standard color scheme is easy to see in the air thanks to the bold white stripes on the top of the wing. The black
striping tape helps to hide any imperfections where the blue and white coverings overlap. You will need the following
materials to finish the Standard version:
 Medium Blue Supercoat Covering- Wing, bottom half of fuselage, stabilizer, and fins.
 White Supercoat Covering- Wing and stabilizer stripes and top half of fuselage.
 Black Supercoat Covering- Front canopy piece.
 1/4" Black SuperStripe Tape- Stripes between whie and blue.

Decal Sheet
-
SIGDKM266A
Begin the wing by ironing on the white stripes. The center stripe should be cut 5" wide, and the outboard stripes should be
2-
5/8". Notice the outside stripes wrap around the leading edge, but only extend about 3/4" back on the lower surface. The
center stripe is used on both the top and the bottom.
The blue is applied in lots of places, starting with the wingtips. Cover each tip with two pieces of material, first the bottom,
then the top. Use the edge of your iron to apply the covering to the concave (bottom) portion of the vortex tips. Finish the
bottom of the wing with two more pieces, carefully cut to overlap the wingtip covering on the outer end and the white
center stripe on the inner end. The upper wing surface will need four pieces of blue covering material. Make all of your
overlaps about 1/4".
Use the same procedure when covering the fuselage, stabilizer, and ailerons. Start with white and finish with blue, again
overlapping 1/4".

.
Engine Installation
The engine shown on the Standard is a Fox .19BB. With schneurle porting and
ball bearings, its power is hard to beat. Unfortunately, it's also hard to find
because this engine is no longer in production. We've shown it here to give you an
idea of how a big, .19
-
size engine looks on the nose.
The performance with a hot .19 is, well, phenomenal! Expect blistering level flight
speeds and vertical climbs that won't stop until you want them to. As great as it
sounds, this kind of power isn't for everybody. It takes a lot of flying experience to
safely handle fast model airplanes of any type. A pilot needs to be one step ahead
of his machine at all times, which can be difficult with a small hot rod like the
Wonder. Yes, with a throttle you can slow it down, but the temptation is to just let it
rip! Remember, the faster a plane flies, the more sensitive it is to control inputs.
Be smooth on the sticks!
Radio Installation
Like all of our Wonders, the receiver is installed behind the fuel tank in the opening in F-3. This Futaba R114H receiver is
pretty small, so it has lots of padding around it. Notice that the servo connection area is left exposed so that the aileron
servo can be plugged in easily when installing the wing.
Size-wise, the S132 servos aren't as big as standard servos, but they're bigger than micros. The throttle and elevator
servos are both attached with servo tape. The 250 maH battery had to be installed next to the elevator servo under the
hatch to offset the weight of the big engine. It's held in place by the servo on one side and a scrap balsa stick.
The aileron servo is mounted to the plywood aileron servo mounts (ASM). Notice the servo arm uses two offset spokes of a
six-spoke servo arm (the other four are cut off). This was done to counteract the slight amount of negative differential that
you naturally get from the swept-forward torque rods. Without getting too technical, what you're looking for is equal up and
down movement of the ailerons. If a straight servo arm doesn't give you equal movement, you can try an offset arm like the
one shown in the photo.
"RUSSIAN" VERSION
This version was styled like Soviet jet
fighters, which typically feature sharp
angular lines. The control surfaces on
the Russian are bigger than the other
versions, but it seems to fly about the
same. All of the Wonders roll and loop
plenty fast!
Covering the "Russian"
The color scheme for this version was loosely translated from a picture that we found of an aerobatic Russian Jet. The
contrastiing red and silver makes it easy to tell the top from the bottom during flight. The Soviets were never too interested
in decorating their airplanes, so the markings on this version were kept pretty simple.

.
To duplicate the color scheme of the Russian, you will need the following materials:
 Fokker Red Supercoat Covering- Top of win and stabilizer, top half of fuselage and fins.
 Silver Supercoat Covering- Bottom of wing and stabilizer, bottom half of fuselage and fins.
 Black Supercoat Covering- Front canopy piece.
 1/16" Black SuperStripe Tape- Rudder outlines on fins.

Decal Sheet
-
SIGDKM266B
In general, cover with silver first followed by red. The red should overlap the silver about 1/8". To keep the edges of the red
covering from "squirming" around, try touching the overlap areas with the iron first. Avoid overheating the plastic covering,
which can pull the edges. The covering on the wingtips has to be cut very carefully to look good. Instead of pushing a knife
or razor blade through the covering, try holding the blade against the cut line while pulling on the excess covering. Take
your time!
The fake rudder outlines on the fins are made with striping tape.
You can cut out the pattern from the plans to help keep them equal in size.
Engine Installation
The Russian flew extremely well with an Enya .15 IV TV. This is a crossflow, plain
bearing engine that's ideal for sport models like the Wonder.
It's not the most powerful .15 on the market, but it's built well, starts easy, and
runs reliably flight after flight. It's best feature is the angled needle valve that helps
keep your fingers away from the propeller while adjusting the mixture.
The wood propeller shown in the photo was something of an experiement. It
actually held up very well through several landings, but eventually broke. Stick
with reinforced nylon props and check them carefully after every flight.
Radio Installation
The radio installation in our Russian prototype is just like the "Typical Engine and Radio Installation" drawing on the plan.
The photos show a standard size Airtronics FM receiver and three standard size Airtronic servos. The 270 maH battery
pack is wrapped in foam below the fuel tank.
The throttle servo is taped to the bottom of the fuselage, but the elevator servo is bolted to hardwood blocks which were
glued to the fuselage side.
Notice the switch is mounted way in the back, under the hatch. On this particular model, the charging jack was routed out
the rear fuselage opening.
The aileron servo on this model used a standard straight-
across servo arm, which worked just fine. Most of the servo wire is
still inside the wing, out of harms way.