Sig Ultimate SIGRC71 Wing Construction

ULTIMATE RC71 FUSELAGE CONSTRUCTION

78.	Draw a vertical line on each side of the fuselage 2-5/8" from the rear. Draw two vertical lines on the back of the fuselage 1/8" in from each side. Taper each side of the fuselage from the 2-5/8" side line to the rear 1/8" line to the achieve a 1/4" thickness (same thickness as the rudder). Start out using a small razor plane and then switch to a sanding block to finish tapering the rear of the fuselage.
79.	Place a small piece of wax paper under the canopy cutout and pin the fuselage down flat. Apply a liberal bead of slow CA glue to the bottom of the canopy and pin it in place on the fuselage. Wipe off any excess glue and allow the glue to cure.
80.	The front wing mount assembly is made up by laminating four laser-cut plywood pieces together, two WMTA's and two WMTB's. Glue the two WMTB's together with SIG Kwik Set Epoxy (5 minute) and allow to dry. Next, glue one of the WMTA's to each side of the laminated WMTB's. The rear wing mount assembly is also made up by laminating four laser-cut plywood pieces together, two WMTC's and two WMTD's. Glue the two WMTD's together with SIG Kwik Set Epoxy (5 minute) and allow to dry. Next, glue one of the WMTC's to each side of the laminated WMTD's.

81.	Install the threaded brass insert into the rear wing mount assembly by threading a 10-32 nut onto a 10-32 bolt. Apply some wax or light oil to the end of the bolt. Thread the brass insert onto the bolt and tighten the nut against the brass insert to lock the brass insert onto the bolt. Next, thread the brass insert into the rear plywood wing mount assembly until the insert is flush with the wing mount. Carefully glue the insert in place using medium CA. After the glue cures remove the bolt from the brass insert.
82.	Place small pieces of wax paper under the fuselage at the wing mount locations and pin the fuselage to the building board. Glue the front and rear wing mount assemblies to the balsa fuselage with SIG Kwik Set Epoxy (5 minute) and allow to cure.
83.	The spacing of the maple engine mounts must be adjusted to fit your particular engine. Measure the width of the crankcase to determine the correct spacing of the maple mounts. Install the maple mounts into the balsa fuselage and adjust the mount spacing by varying the thickness of the scrap balsa spacer under the bottom mount as shown on the fuselage plan.
84.	Because the fuselage is routed to shape (not band sawed) the engine mount slots have a slight radius at the rear. Slightly round the ends of the maple engine mounts for a flush fit. Glue the maple engine mounts in place along with the proper balsa spacer with SIG Kwik Set Epoxy (5 minute) wipe off any excess epoxy glue with isopropyl alcohol and allow the glue to cure.
85.	Glue the 1/2" sq. x3" balsa fuselage fill-in to the front of the fuselage and the maple engine mounts with medium CA .

86.	Place a small piece of wax paper on your building board and pin the fuselage to the building board with the cabane cutout over the wax paper. Make sure the LEFT SIDE OF THE FUSELAGE IS DOWN!!! Glue in place the laser-cut 3/16" plywood cabane strut along with the laser-cut 5/16" balsa cabane fill-in with SIG Kwik Set Epoxy (5 minute). Wipe off any excess glue and weight the assembly down with a stack of old books or metal weights until the glue cures.
87.	Taper the ends of the left and right fuselage doublers with a razor plane or sanding block. Make sure you taper the outside ends of the doublers - NOT THE INSIDE ENDS.
88.	Glue the left laser-cut 1/8" plywood doubler to the left side of the fuselage using a liberal amount of SIG Kwik Set Epoxy (5 minute) applied to the inside of the doubler. Hold the doubler in place until the epoxy glue has cured with either metal weights or a stack of old books. Apply a liberal amount of SIG Kwik Set Epoxy (5 minute) to the inside of the right laser-cut 1/8" plywood doubler (the one with the engine cutout) and glue the to the right side of the fuselage. Hold the doubler in place until the epoxy glue has cured, with either metal weights or a stack of old books.

89.	Use a razor plane to roughly round the edges of the plywood doubler and the balsa fuselage. Finish shaping the fuselage and doublers with a sanding block equipped with 80 grit sandpaper. Blend all the corners and smooth the flat areas with 220 grit sandpaper.
90.	Wrap a piece of 80 grit sandpaper around a 3/4" dowel and sand a half round shape in the 1/2" sq. balsa fuselage fill-in (between the maple engine mounts) to provide clearance for the crankcase of your engine.
91.	The injection molded engine mount was designed to accommodate a wide range of engine sizes (.25 to .45). Depending upon which size engine you use, it may be necessary to trim the insides of the mount to fit your particular engine. Scribe lines have been provided on the face of the mount as a guide for cutting. Carefully measure your engine and trim an equal amount from each side of the mount until your engine fits into the mount without spreading the mount.
92.	Place the engine and the injection molded engine on parallels or on a vise opened so that the motor mount sits only on the top face of the jaws. Mark the mounting hole locations with a center punch or a sharpened piece of music wire. Drill four holes through the molded mount at these locations with a 1/8" diameter drill bit.
93.	Install the proper size propeller and spinner on the engine and place it and the molded mount on the fuselage as shown in the photo. Make sure you have a 1/8" gap between the spinner and front of the fuselage. Mark the mounting hole locations with a center punch or a sharpened piece of music wire.
94.	Drill out the four engine mounting bolt holes in the previously marked locations with a 1/8" diameter drill bit.
95.	Drill the back side of each of the four engine mounting holes 3/16" deep with a 5/32" diameter drill bit for blind nut clearance. Note: The 4-40 blind nuts will be permanently installed after the fuselage has been covered.

96.

The landing gear bolt hole locations have already been laser-cut into the right plywood doubler. Drill through the fuselage with a 5/32" diameter drill bit using the two holes as a guide.

97.

Because the fuselage is routed (not band sawed) you will have to square off the wing cut out just behind the rear wing mount. Refer to the drawing (near right) and notch the rear of the wing opening as shown.

98.

Place the fuselage on the bottom wing and carefully measure from the rear of each wing tip to the rear of the fuselage as shown in the drawing (far right). The rear of the fuselage should be an equal distance from each wing tip. When satisfied with the measurements, place alignment marks on the bottom of the fuse and wing using a soft lead pencil. Remove the wing from the fuselage.

99.

Place a sharpened piece of 1/8" dowel or music wire about 7/8" long into the threaded brass insert. Reinstall the wing onto the fuselage and line up the previously made alignment marks. Lightly press down on the rear of the wing - the sharpened dowel will leave a small indentation in the balsa aileron fill-in. Drill a 3/16" diameter hole through the balsa aileron fill-in at the indentation.

100.

Sand a bevel in the front edge of the laser-cut 1/16" plywood wing reinforcement (WBR) so that it will lay flat on the bottom of the aileron fillins. Glue the reinforcement in place as shown the photo. The hole in the reinforcement should line up with the previously drilled hole in balsa aileron fill-in.

101.

Bolt the wing onto the fuselage and lightly tighten the 10-32 nylon bolt and check for any gaps between the fuselage wing saddle and the bottom wing. Sand off any high points on the fuselage wing saddle and/or the top of the bottom wing. There must be good fit between the fuselage wing saddle and the wing. If the wing is not perpendicular to the fuselage now is the time to adjust the wing saddle to achieve this.

THE PERFECT WING SADDLE (Optional)

To produce the perfect wing saddle the following method has proved to be effective. Sand away just enough of the balsa fuselage and plywood doublers so there is a slight gap between the wing saddle and the wing. Do not sand the laminated plywood wing mounts or you will change the wing incidence. Tape a piece of Saran Wrap (or an equivalent plastic wrap) to the top of the bottom wing and wrap it around the leading and trailing edges. Use pieces of masking tape to hold the plastic wrap perfectly flat and smooth on the wing. Give the wing dowel and the 10-32 nylon bolt a coat of paste wax.

Thoroughly mix two equal parts of SIG Epoxolite putty (EP-001) together and spread this mixture on the fuselage wing saddle, keeping it away from the wing dowel hole and threaded brass insert. Next, bolt the wing onto the fuselage and tighten the 10-32 nylon bolt. The Epoxolite putty should ooze out from under the wing saddle. Make sure the wing and fuselage are perpendicular to each other and allow the putty to cure for 3-1/2 to 4 hours and then carefully remove the wing and the plastic wrap from the fuselage.

The putty at this time will not be totally cured, but it will be firm enough to allow you to trim the excess putty. Use a sharp modeling knife or a single edge razor blade and trim the putty flush with the balsa fuselage and the plywood doublers. After 24 hours lightly sand the sides of the fuselage and the Epoxolite with a 220 grit sandpaper to remove any imperfections.

Fin And Rudder

102.

Pin in place over the plan the laser-cut 1/4" balsa fin parts F-1 and F-2 and the rudder parts R-1, R-2, R-3 and R-4. Glue these parts together by flowing thin CA down into the joints (you didn't forget the waxed paper did you?). Apply a second coat of glue to the joints with medium CA and allow the glue to soak into the joint for a few seconds, and then wipe off any excess glue with a rag.

Stabilizer And Elevator

103.

Pin in place over the plan the laser-cut 1/4" balsa stabilizer parts S-1 and S-2. Use the same procedure as the previous step to glue the parts together.

104.

Pin in place over the plan the laser-cut 1/4" balsa elevator parts E-1, E-2 and E-3 for both of the elevators using the same gluing procedure that is illustrated in step No.102. Glue the 1/4"x4" dowel elevator joiner to both of the elevator halves using SIG Kwik Set Epoxy (5 minute).

105.

Using a long sanding block and 220 grit sandpaper, sand both sides of the fin, rudder, stabilizer and elevators.
NOTE: Any imperfections that are not removed will show through the covering.

106.

Using a sanding block and 220 grit sandpaper, carefully round (1/4" diameter) the leading edges of the stabilizer, elevators, fin and rudder. Next, round the trailing edges of the elevators and rudder including the bottom of the rudder.

107.

Drill a 1/16" diameter. hole in the bottom of the rudder as shown on the plan. Use a modeling knife and cut a 1/16" deep slot in the bottom of the rudder and glue in place the pre-bent tailwheel wire with thin CA glue. Soak the balsa wood surrounding the wire with thin CA glue.

108.

Reinforce the tailwheel wire with a piece of glass tape (not provided) and thin CA glue.

109.

With all the control surfaces finished it's time to drill the holes for attaching the control horns and interplane horns to the ailerons, the control horns for the rudder and elevator, and the push rod guides in fuselage. Place the control surfaces and the fuselage over the plans and mark the hole locations. Using a 3/32" drill bit and a pin vise, drill a hole in each location.

BUILDERS TIP:

Apply a few drops of thin CA to each side of the holes and allow the glue to cure and then redrill each hole. This hardens the balsa around the holes and prevents the control horns from smashing into the wood when the screws are tightened.

Wheel Pants
110.	True up the edges of each of the wheel pant halves by gently sanding them against 220 grit sandpaper placed on a flat surface.
111.	Using the measurements that are shown in the photo, glue in place the wheel pant reinforcements (WPR) with thin CA. Make sure that you glue one WPR to the inside of a left and right wheel pant half.
112.	There are two 5/32" holes that have been laser-cut in the wheel pant reinforcement. Drill through the ASS plastic in each of these locations with a 5/32" drill bit.
113.	Drill a 5/32" hole in the side of the ASS wheel pant at the top of the slot in the wheel pant reinforcement (WPR), This hole is to help cut out the ASS plastic from the slot.
114.	Using a razor saw, cut through the ASS wheel pant on both sides of the slot in the laser-cut plywood reinforcement (WPR) as shown in the photo, Remove the excess ASS plastic from the slot with a modeling knife,

115.	Gently tap in place the two 4-40 blind nuts to the inside of each of the wheel pant halves. Glue the 4-40 blind nuts in place with medium CA.
116.	Use small pieces of masking tape to hold the pants together and to align the two halves. Apply thin CA to the seams of the wheel pants and allow the glue to cure.
117.	Roughly cut out the wheel opening in the bottom of the wheel pants with a Dremel tool and a sanding drum, Remove only the flat sections from the bottom of the ASS pants, Use a modeling knife and sandpaper wrapped around various sizes of dowels to finish cutting out the wheel opening,
118.	Place a #6 flat washer onto the 6-32 x 1-1/2" bolt (axle) and then slide the 2-1/4" wheel (not provided) over the axle. Add another #6 flat washer and thread on a 6-32 hex nut. Try for a clearance between the washer and the wheel that allows the wheel to turn freely, yet does not allow the wheel to wobble. Next, thread a 6-32 aircraft locking nut backwards onto the axle and tighten it up against the 6-32 hex nut.

119.	Install the 6-32 axle and the wheel onto the aluminum landing gear and thread on a 6-32 aircraft locking nut. Use a small 5/16" open end wrench to hold the locking nut next to the wheel and securely tighten the outside 6-32 aircraft locking nut. One point on the 6-32 locking nut that is next to the wheel must be pointed up to match the slot in the ABS wheel pant.

120.

Place the wheel pant over the wheel and slide it over the 6-32 locking nut. Securely fasten the wheel pant to the aluminum landing gear by threading the two 4-40 x3/8" socket head bolts through the aluminum landing gear and into the 4-40 blind nuts in the ABS wheel pants. This type of wheel pant attachment allows for quick and easy wheel pant removal and installation.

COVERING AND FINISHING

Covering Notes

All of the Ultimate prototypes were covered Sig Supercoat iron-on plastic covering. Supercoat covering is ideal for sport models because it is light weight and easy to apply. The color scheme pictured on the label is quite easy to duplicate and only requires two rolls of Sig Supercoat covering covering (SCC415 Medium Blue). In addition to two rolls of covering you will need one four ounce jar of Supercoat clear butyrate dope (SIGLC001), and one four ounce jar of Supercoat medium blue butyrate dope (SIGSD033) to paint the cabane, the inside of the motor mount area, the wing interplane attachment points and the ABS hatch covers and wheel pants. This color matches the Supercoat iron-on plastic covering. The three decal sheets that are provided in the kit have the remaining markings to complete the color scheme.

NOTE: If you choose another brand of covering material, be sure to read the manufacturer's directions that come with the covering material. Follow their instructions when applying the material as different brand coverings have slightly different handling characteristics and application temperatures. However, the basic techniques for applying the iron-on plastic coverings of any brand are pretty much the same. We also recommend that you use a temperature gauge to set the temperature of your iron to the setting the covering manufacturer recommends (200 F. for Sig Supercoat covering).

BUILDERS TIP:
Before starting the actual application of the covering material, use a vacuum cleaner with the soft brush attachment and vacuum the entire model and work bench. This helps eliminate the dust particles that get under the covering.

Covering The Fuselage

121.

The structure that is to be covered must be clean, dry, and dust free. Wipe the entire model with a tack rag or a cloth dampened with alcohol to remove all excess balsa dust.

122.

Cut or trace out a pattern of the fuselage profile from the plan. Use this pattern to cut out a piece of covering for each side of the fuselage (right and left). Allow approximately 1" of excess covering material around the outside edges of the fuselage. Place the covering material on the fuselage side and smooth out as many wrinkles as possible. Iron the covering in place overlapping the covering around all the outside edges of the fuselage. Repeat this step for the other side of the fuselage and overlap the seams of the covering material by at least 1/4".

Covering The Wings

123.

Start by covering the inside piece of the aileron fill-in with a 1/2" x 2" piece of covering. Overlap the covering onto the top of each aileron fill-in and iron the covering in place. Use a sharp modeling knife or a single edge razor blade and trim off the excess covering leaving only a 1/8" overlap on the top and bottom of the aileron fill-in.

124.

Cover the end of each wing tip making sure you overlap the covering material around and onto the wing sheet and cap strips about 1/8".

125.

Working with half of a wing at a time, cover the bottom of the wing and then the top. This leaves the front seam overlapped on the bottom where it is less visible. Cut the covering to size, allowing approximately 1" excess around the outside edges of the wing panel.
Place the covering onto the wing panel and tack the covering in place all around the outside edges with a sealing iron (set at 200 for Sig Supercoat). Once it is smoothly tacked in place, work completely around the outside edges, sealing the covering entirely to the structure. Don't try to shrink the covering tight at this time.

126.

Trim off the excess covering with a modeling knife or a single edge razor blade. Leave the covering wrapped around to the top edge of the trailing edge and on the centerline of the leading edge. Be sure to leave an overlap in the center of the wing panels.

127.

Repeat the procedure in step NO.125 and cover the top of the wing. Overlap all seams at least 1/4".

128.	To shrink the covering down tight in the inner areas, we recommend that you use a heat gun. You need a special heat gun that is made specifically for shrinking model coverings. If you do not have a heat gun, you can use your sealing iron to shrink the covering tight. Cover the iron with a sock and turn up the temperature a little more than it was for sealing the edges to compensate for the sock. The sock helps eliminate most of the scratches caused by a bare iron. Move the heat gun or iron slowly back and forth over the surface of the wing, allowing the heat to shrink all the covering material on that side at the same rate. Keep the heat gun moving at all times, holding the nozzle about 4" to 6" above the covering. If you stop moving for too long, or hold the gun too close, you will melt a hole in the covering.
129.	Repeat steps No.123 through No.128 to cover the remaining wing panels.
130.	Reseal the overlapping edges of the covering material with a sealing iron. Make sure that the covering is attached to each of the ribs, spars and the leading and trailing edges.
131.	Cover the stabilizer, fin, rudder, elevators and interplane struts using the same techniques as used for covering the wing.
Installing Sig Easy Hinges
	SIG's famous EASY HINGES have been included in your kit to hinge all the control surfaces. Each ultra-thin hinge is actually a three-part laminate, a tough plastic inner core with an absorbent wicking material laminated to each side. They are specially designed to be installed with thin CA glue. The hinges have been chemically treated to slow down the set time of the glue to allow it to soak all the way to the ends of the hinge and into wood surrounding it for super strong bond. Once the glue has dried, the hinge cannot be pulled from the structure without tearing wood out with it! We recommend that all surfaces be completely covered before installing the EASY HINGES.
132.	Use an #11 X-Acto blade (or similar) to cut slots in the stabilizer trailing edge and elevator leading edge to accept the EASY HINGES. Make the slots approximately 1/2" in depth and slightly wider than the hinge. Refer to the full-size plan for the exact hinge location.
133.	After all 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 elevators onto the hinges at an angle, one at a time, instead of trying to push it straight onto all the hinges at once. Don't be concerned if the hinges aren't perfectly straight or centered in the slots - they don't have a center line.
134.	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.
135.	Place three or four large drops of thin CA directly onto the hinges in the gap. The glue will wick into the slots as it penetrates both the wood and the hinge. Continue this process, gluing the same side of the EASY HINGES. Then turn the stabilizer over and repeat the gluing process on the other side of each hinge.
136.	After the glued has cured (15 to 20 minutes) the joint should be flexed to full deflection in each direction a couple dozen times to reduce the stiffness. Don't worry about shortening the life of the hinges, as they are almost indestructible.
137.	The ailerons and the rudder are hinged exactly like the stabilizer and elevators. When you assemble the rudder to the fin DO NOT glue the bottom hinges in the rudder and exposed wood parts.
Painting The Wheel Pants And Hatch Covers
138.	Prepare the wheel pants and servo hatch covers for painting by lightly sanding them with 360 or 400 grit sandpaper. Brush on three coats of Sig Litecoat clear dope onto the wheel pants and each of the servo hatches. Allow each coat to dry thoroughly and lightly sand them with 360 grit sandpaper before applying the next coat. Next, spray on two or three light coats of Sig Supercoat color (Medium Blue SD-276 in a 16 oz. spray can). Allow plenty of time for the dope to dry between each coat. Because butyrate dope dries very quickly, do not attempt to spray butyrate dope in cold weather or in high humidity. This will cause the dope to blush (turn cloudy). If you do see blushing, wait until a dryer and/or warmer day and spray another light coat of dope to remove the blush. CAUTION: Spray paint in well ventilated areas only.

139.

Brush three coats of SIG Litecoat clear dope on the following areas: engine cutout, upper wing cabane, upper and lower wing interplane attachment points, interplane struts. Without scratching the covering, lightly sand all these areas. Now brush or spray two or three light coats of SIG Supercoat color (Medium Blue) on all of the above areas. A little bit of overlap (1/16") of dope onto the covering will assure a fuel proof seam.

Applying The Decals

The decals that are included in this kit closely represent the markings of the full scale ULTIMATE 10 DASH 300S Bluehawk. The letters "Bluehawk" in the large decal sheets were intentionally left clear so the lettering would match the many different brands and shades of coverings that are available. The wing and fuselage decals for the ULTIMATE are very long and are printed in two parts to make them easier to apply.

140.

Cut out the decals using a modeling knife equipped with a sharp (new) No. 11 X-Acto blade and a straight edge. Leave about 1/32" to 1/16" of clear Mylar all around the outside edges of each decal.

141.

Measure the location of the fuselage decal on the plan and place small pieces of masking tape along one edge on the side of the fuselage as positioning guides. The fuselage decal is applied from the tail forward using the stabilizer cutout and the trailing edge of the fuselage as a starting point. Once the rear half of the decal is correctly positioned overlap the front half of the decal about 1/16" over the rear half and work towards the front of the fuselage. Carefully squeegee the water from under the decal to lock it into position.

Repeat this procedure for the other side.

142.

The top wing decal is applied in the same manner as the fuselage decal. Start at one wing tip and work across the wing.

143.

Locate the other decal positions and apply the remaining decals to the sides of the fin, rudder and fuselage.

BUILDERS TIP:
Find an empty window cleaner bottle and sprayer. Fill the bottle with water and add 6 to 10 drops of dishwashing detergent to the water and shake. Spray this solution onto the back of the decal and onto the surface on which they are to be placed. This procedure will allow you to position the decal in it's proper location without sticking to the covering. When satisfied with the location of the decal, squeegee out the soap and water solution from under the decal with an epoxy spreader or balsa paddle. Allow the decal to dry for at least 12 hours before flying.

Final Assembly

144.

Bolt the bottom wing to the fuselage. Place the stabilizer in the slot in the rear of the fuselage. Refer to the top view alignment drawing, and carefully align the stabilizer to the wing. When satisfied with the alignment, draw cut lines on the top and bottom of the stabilizer at the fuselage sides. Cut away the covering on the top and bottom of the stabilizer where it will be glued to the fuselage (there must be wood to wood contact in the joints). Use a sharp modeling knife or a single edge razor blade to cut the film. If possible do not cut any wood, just film.

145.

Glue the stabilizer onto the fuselage using slow drying epoxy (SIGEG001) to allow you ample time to carefully re-align the stab with the fuselage. Check and double check the alignment of the stabilizer from the rear of the fuselage making sure that the stab is perpendicular to the fuselage and parallel to the wing. Pin the stabilizer in place and allow the glue to cure.

146.

Cut a hinge slot in the rudder and in the rear of the fuselage for the bottom rudder hinge. Using Sig Kwik Set Epoxy (5 minute), glue the fin and rudder assembly into the pre-cut slot in the rear of the fuselage. DO NOT glue the bottom hinge! As you mate the fin to the fuselage, insert the bottom rudder hinge into the fuselage. Refer to the alignment drawing and make sure the fin and rudder are aligned perpendicular (90�) to the stabilizer. When satisfied with the alignment, pin in place and allow the glue to cure. After the epoxy has cured, glue the bottom hinge into the rudder and fuselage with thin CA, as was done for all the other hinges.

147.

Install the aluminum landing gear onto the fuselage using the two 6-32 x 1-1/2" bolts and locking aircraft nuts. After tightening the nuts, cut the excess 6-32 bolt flush with the aircraft locking nut.

148.

Install a 3/4" diameter tailwheel onto the tailwheel wire with a 1/16" wheel collar or with soldered small flat washers.

149.

Install the 4-40 blind nuts in the cabane and interplane strut attachment tabs. Using a pair of pliers, press each blind nut into the laser-cut hole and glue.

Installing The Tank And Engine

150.

In preparation for mounting the engine, install the four 4-40 blind nuts in the previously drilled holes. Lightly tap the blind nuts in place with a small hammer and glue in place with thin CA. Paint the blind nuts to match the color of the fuselage.

151.

Securely mount the engine and molded mount onto the fuselage using the four 4-40 x1-1/4" socket-head bolts that have been provided.

152.

The fuel tank shown in the photo and on the fuselage plan is a Sullivan 4 oz. slant tank (SS4). You will notice the overflow vent/pressure vent is located in the upper left hand corner of the tank. This is to allow the fuel tank to be completely filled when the model is setting on its wheels. The pick up tube (clunk) must extend to the rear of the fuel tank and swing freely to all the corners inside the fuel tank.
Place the fuel tank on the fuselage and mark the locations of the four 4-40 J-bolts. Keep them close to the sides of the tank. Drill a 1/16" hole in each of these four locations and thread the J-bolts in place. Place a small drop of thin CA on the threads of each J-bolt to lock them in place. Insulate the fuel tank from vibration by placing a piece of foam rubber under the fuel tank and rubber band it in place with two No. 64 rubber bands.

OPTIONAL FUEL TANK:
The 4 ounce fuel tank that is shown on the plan allows flight times of 5 to 7 minutes. This is more than adequate for most pilots. However, if additional flight time is desired, there is enough room on the side of the fuselage to install a Sullivan 6 ounce slant tank (SS6).

Radio Installation

153.

Mount the two small nylon control horns onto the ailerons, the two medium control horns onto the elevator and rudder, and the four interplane connect horns in the previously drilled mounting holes in each of the control surfaces. Mount each of the control horns with the No.2 x1/2" sheet metal screws that have been provided. Do not crush the balsa control surface by over tightening the sheet metal screws.

154.

The servo output arms that are supplied with the servos (or the radio system) are equipped with four arms, trim off two of the short arms and one of the long arms. Make sure that all the servo output arms are the same length for the ailerons, rudder and elevator. This is a good time to assemble all of the components of your radio system together (servos, receiver, battery and switch harness) and bench test it. Set all the trim levers on the transmitter to their neutral positions and turn on the transmitter and the receiver. Install the servo output arms onto the elevator, rudder and the two aileron servos. Make sure that the servo output arms are perpendicular to the servo. Make sure all of the servos are working properly and turn off the radio system.

155.

Reinstall the throttle servo in the right servo hatch as described in Step No. 76.

156.	Using the measurements that are shown in the photo, trial fit each of the servos onto the ABS hatches making sure that the servo output arm is centered in the hatch fairing. Mark their proper locations on each hatch with a soft lead pencil. Wipe clean the sides of the servos and the ABS hatches with isopropyl alcohol to remove any oily residues. Apply two strips of the 1/16"x1/2" servo tape to the bottom sides of the elevator and rudder servos. Remove the paper backing from the tape and press each servo in place on the bottom of each hatch.
157.	Reinstall the aileron servos with output arms into the wing. Make the aileron push rod by threading one of the nylon RC links onto the end of a 2-56 threaded rod until the end of the threads protrude into the clevis throat. Next, attach a 2-56 solder link to the servo output arm on the servo and connect the nylon RC link to the aileron control horn. With the aileron in the neutral position, cut off the excess rod with a pair of side cutters. Make sure that you leave enough wire for a solid solder joint in the solder link. Mark the location of the end of the solder link on the rod. Remove the solder link from the aileron horn, line up the end of the solder link with the mark and solder the link to the end of the rod. Snap the solder link on the aileron horn. Repeat this step to make the other push rod.
158.	Wrap the receiver and the battery pack in 1/4" foam rubber. Install the receiver in the leading edge of the right wing and the battery pack in the leading edge of the left wing. Make sure that the receiver and the battery pack fit snugly into their openings. Pass the antenna wire through the antenna tube and out the wing tip of the left wing.
159.	Install each ABS hatch assembly onto the wing with four No.2 x1/4" sheet metal screws.
160.	Bolt the bottom wing to the fuselage.
161.	Two 1/16" diameter x 24" music wire pushrods have been provided for the elevator and rudder. Make the elevator push rod by soldering one of the 2-56 threaded brass couplers (provided) to one end of the music wire pushrod. Thread a nylon RC link halfway (see step #157) onto the threaded brass coupler. Attach a 2-56 solder link to the servo output arm and connect the RC link to the nylon elevator control horn. Slip two pieces of 1/8" o.d. x1/2" nylon tubing over the 1/16" music wire push rod. These pieces of nylon tubing will be part of the pushrod guides in a later next step. Using a pair of side cutters, cut off the excess music wire leaving enough wire to allow a solid solder joint in the solder link. Mark the location of the end of the solder link on the rod. Remove the solder from the servo output arm, line up the end of the solder link with the mark and solder the link to the music wire push rod.
162.	Attach the push rod to the elevator control horn with the nylon RC link and to the servo output arm with the solder link.
163.	Repeat steps No. 161 through No. 162 to make the rudder pushrod.
164.	Place one LG clip onto each of the nylon tubes (that were previously installed) and place a small drop of CA to hold them firmly to together. Refer to the plan and insert two 2-56 x 1" bolts into the LG clip and slip two LG straps onto the 2-56 bolts. Pass the bolts through the (previously drilled) holes in the fuselage and install two additional LG straps onto the 2-56 bolts. Next, install the LG clip and nylon tube from the opposite side of the fuselage onto the 2-56 bolts. Secure the push rod guides in place with two 2-56 hex nuts and place a small drop of CA onto the hex nut and bolt to lock them in place. Repeat this step for the other pushrod guide.
165.	Insert a ball rivet into the throttle servo output arm and hold the head of the ball rivet in a vise or against a metal object. Peen the end of the rivet over with a small hammer as shown in the photo. Install the output arm onto the throttle servo.

166.

Make the throttle push rod by threading a 2-56 nylon ball link onto a 2-56 x .078 I.D. threaded brass coupler. Snap the nylon ball link and brass coupler on to the rivet ball on the throttle servo arm. Thread a nylon RC link onto a 2-56 threaded rod and attach the RC link to the throttle lever on the engine. Set the throttle servo and the carburetor lever in the middle of their travel limits. Using a pair of side cutters, cut off the excess rod, leaving enough wire to allow a solid solder joint. Mark the end of the brass coupler on the rod. Remove the nylon ball link from the brass coupler and solder the threaded brass coupler to the end of the rod. Thread the nylon ball link onto�the 2-56 brass coupler and snap the ball link into the rivet ball on the servo arm.

167.

Bolt the top wing in place using the (10) 4-40 nylon socket head bolts and the (10) No.4 nylon flat washers that have been provided. The nylon bolts will shear off if the model is involved in a crash and this will help minimize the amount of damage the model will sustain. Make sure you do not overtighten the nylon bolts with the allen wrench.

168.

Make the two interplane pushrods in the same manner as the aileron pushrods in step No. 157 of this instruction book.

Radio Setup

169.

Use the aileron positioning guide to check the neutral position of each aileron. Place the guide on the bottom of the wing. Adjust each of the ailerons to its neutral position by screwing the nylon RC link in or out until the aileron sits flush on the guide.

170.

NOTE: Make sure the transmitter and receiver are turned on and the transmitter sticks and the trim levers are centered before adjusting any of the control surfaces.

The elevator and rudder must also be in the neutral position. Screw the nylon RC links in or out to adjust these control surfaces.

171.

Place the model on a flat surface and measure the amount of elevator travel with a ruler as pictured in the photo. Adjust the elevator travel to the dimensions that are listed in the chart.
NOTE: If you are using a 4-channel radio without dual rates, use the low rate dimensions for the first few flights.

172.

Check and adjust the aileron travel as per the dimensions in the control travel chart. Because there are so many different manufacturers of radio control equipment, it would be almost impossible to tell the modeler how to set up each type of radio for their ULTIMATE. Below is a chart that gives the modeler the suggested control travel for each of the control surfaces of the ULTIMATE. The second chart deals with radios that have mixing capabilities. Listed are the types of mixing that are desirable and the effects they have on the flight performance of the ULTIMATE.

Control Travel Chart
Item	Low Rate Travel	High Rate Travel
ELEVATOR	3/4" up 3/4" down	1-1/4" up 1-1/4" down
AILERONS	3/8" up 3/8" down	9/16" up 9/16" down
RUDDER	1-1/2" It. 1-1/2" rt.	2" It. 2" rt.
THROTTLE	Full Range of throttle lever on Carb

NOTE:
The control throws that are listed are a good starting place. When the modeler feels more confident with the ULTIMATE, the control throws can be increased (a little at a time) to a maximum of 45� for the elevators and ailerons.

Control Mixing Chart Chart
Mixing	Control Surfaces	Effect
FLAPERON	Elevators and Ailerons	Flaperon mixing is a desired feature because it allows the ailerons to continue to work while the flaps are deployed (or mixed). EXAMPLE: When the flaps are in the down position and you make a right turn, the right aileron raises up allowing the model to turn in that direction.
ELEVATOR FLAP	Elevators and Flaps	Elevator to flap mixing is also a desired feature. It allows the flaps and elevators to work together but in the opposite directions of each other (When mixed together, if the flaps travel downward, the elevators travel upward and vise versa). This gives the ULTIMATE the ability to make super sharp turns and loops.
3-POSITION SWITCH	Flaps and Elevators	Depending upon your brand and type of radio, the three position switch located on the transmitter may be used to set the flaps in three different positions.
		Switch setting #1. Kick the flaps up approximately 10�. The flaps now act like the spoilers of a sailplane killing part of the lift of the wing. This allows the ULTIMATE to make a faster descent for those quick take-offs and landings for which fun fly models are known.
		Switch setting #2. With the switch in this position, the flaps are held in the neutral position with the exception of the elevator to flap mixing for normal flying.
		Switch setting #3. Lower the flaps about 30�. This allows the ULTIMATE to make very slow landings or to fly forward at a speed that is almost a hover.

Balancing Your Ultimate

For optimum flight performance balance the ULTIMATE precisely where indicated on the fuselage plan. Place a mark (a piece of masking tape) on the bottom of the cabane strut 1-3/16" from the back edge. Place the tip of your finger under the mark and lift up the model. If necessary, add small pieces of stick-on lead weights to the nose or tail to properly balance the model. Another method of adding or removing weight is to balance the model with different types of mufflers and spinners.
EXAMPLE: If the model is tail heavy, try using a heaver muffler and/or an aluminum spinner. If the model is nose heavy use a lighter weight muffler and/or spinner.

Pre-Flight Checkout

Make sure the servos are securely mounted and that the servo arms have their retaining screws in place. It is also a good idea to re-check all the push rod connections, fuel tank mountings, fuel lines, wheels, engine mounting bolts and tighten the prop and spinner. Range check the radio as per the manufacturer's instructions and make sure it is fully charged. If there are any problems, send the radio in for repair before you attempt to fly.
DOUBLE CHECK EVERYTHING YOU CAN THINK OF! A model and radio that are not prepared and working properly on the ground before take-off will not improve in the air- IT WILL GET WORSE!!!! There is no point in attempting to fly the model until everything is 100% correct.

Flying

The ULTIMATE can be dialed in to go from mild to wild. It is really a matter of preference how the modeler wants to set up and fly this model. With the control throws on the low rate setting, the Ultimate is quite easy to fly and can be handled by most intermediate RC pilots. However, once you turn on the high rate setting, it is a whole new ballgame. The Ultimate is very responsive and can perform just about any maneuver that you can think of in a heart beat. One of my favorite maneuvers with the Ultimate is to fly down the runway at about half throttle, pull the nose up slightly and execute a right snap roll recovering the model upright, and then executing a left snap roll and recover upright. Once you get the hang of it, you can do as many snap rolls in a row as you want. Like other fun fly models, the Ultimate was designed for close in flying. Always use good judgement and never place yourself or fellow modelers in harms way!!

SIG MFG. CO., INC............Montezuma, Iowa 50171-0520