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Basic Fuselage Construction

 
32.

 

a. Tape or rubber band the fuselage sides together at the rear.  
b. Working from the rear forward, slip all the fuselage formers (F-6 thru F-1) 

into place. Put a rubber band around the fuselage at each former location 
to hold it tightly together.  

c. Slide the die-cut Lite-Ply part FBR (fuselage bottom, rear) under the rubber 

bands until it snaps into its proper location between the fuselage sides.  

d. Slide the cockpit floor into place under the rubber bands. 

NOTE: The "Tee-Lock" tabs on the formers, FBR, and the cockpit floor are made 
oversized to protrude past the fuselage sides. These will be sanded off after the 
fuselage has been completely assembled.

 
33.

 

a. Place the fuselage over the top view on the plans to check its alignment. Correct if necessary by twisting gently 

before proceeding. Be certain that the joint where the fuselage sides meet at the rear is square with the fuselage 
bottom.  

b. Carefully glue all of the parts permanently in place, preferably working from inside of the fuselage, using medium CA. 

Start with small patches of glue in the corners, checking the fuselage alignment as you go. Then go back and glue all 
of the joints on both sides. Leave the rubber bands and tape in place until all of the glue has dried completely. 

 
34.

 

a. Glue the die-cut Lite-Ply instrument panel lP to the tab on the front of the cockpit floor.  
b. Glue the die-cut Lite-Ply headrest HR into the slot in the cockpit floor. Use the 250 side of the Dual Tool to get the 

correct angle. 

 
35.

 

a. Glue the three 3/16"x1/4"x18" balsa fuselage stringers in place.  
b. When dry, trim off the front of the stringers flush with the front of HR. 

 

 

 

 
36.

 

a. Bevel the top edge of the fuselage sides with a sanding block to provide a firm seat for the fuselage top deck when it 

is installed. Notice that the angle between the top deck and the fuselage sides varies along the entire length. Don't 
worry about perfection - a few swipes with a sanding block on each side should do the trick.  

b. Tape the die-cut balsa fuselage top deck in place. You may need to apply some water to the outer surface of the dop 

deck to make it easier to bend into position and prevent it from cracking. Once again, check the alignment of the 
fuselage over the plans.  

c. Working from the inside, glue the top deck in place.  

d. When dry, remove the tape. 

 
37.

 

a. Cut two braces for F-1 from the 1/2"x24" 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.  

b. Install the die-cut Lite-Ply tank floor in the fuselage. Be certain it is seated on the fuselage doublers and against the 

back of F-1, then glue it in place. 

 
38.

 

a. Install the landing gear mount to the fuselage by gluing it firmly to the sides, the doublers, and the bottom of F-2.  
b. Tape FBF (fuselage bottom, front) in place then glue it using medium CA. Be sure to firmly glue the joint between 

FBF and the landing gear mount from the inside of tne fuselage. 

NOTE: The hole in FBF is provided to serve as an oil drain hole, as well as a convenient place to route-the vent-line from 
the fuel tank and/or the breather line from the crankcase of a four-stroke engine.

Summary of Contents for Four-Star 40 SIGRC44

Page 1: ......

Page 2: ...on the fuselage instead of the wing simplifies wing construction and lowers the parts count The tailwheel is a bit unique in that it s attached directly to the rudder without the usual plastic tailwheel bearing We ve tested this installation quite extensively without any problems The amazing strength of EASY HINGES and cyanoacrylate adhesive make this simple effective tailwheel installation possib...

Page 3: ... in contact and positioned correctly before glue application This feature is useful when laminating large sheeted areas like a fuselage side and a fuselage doubler Sig Kwik Shot Accelerator Spraying accelerator 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...

Page 4: ...lable Plan ahead Read the book completely and study the full size plans before beginning construction Refer to The Basics of Radio Control In addition to the instruction booklet you are reading now the booklet The Basics of Radio Control has been included with this kit as a reference for installing the engine fuel tank and radio in the FOUR STAR 40 It also contains very important information on pr...

Page 5: ...ottle pushrod 4 2 56x10 Threaded Rods 2 ailerons l elevator l rudder 15 Easy Hinges 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 Crooked models don t fly well The building board can be a table a workbench a reject door core from the lumber yar...

Page 6: ...ng ribs to the spars and trailing edge sheeting b Place scraps of 1 16 balsa near the main spar to accurately space the W 1 wing ribs up from the building board The spacing is required for the center sheeting to be added later c Use the dihedral guage side of the die cut Dual Tool to set the root W 1 rib at the proper dihedral angle before gluing it in place Add the two remaining W 1 ribs 3 a Glue...

Page 7: ... step Otherwise you may find it difficulf to remove your wing from the board later 6 Pieces for the top center sheeting should be cut from the 1 16 x3 x30 balsa provided in the kit Again Sig Bond is recommended for the front and rear edges of the sheeting to make it easier to sand the joints smooth Also use Sig Bond on the center W 1 rib The sheeting can be glued to the ribs on each end using CA 7...

Page 8: ...own in the photo Using a modeling knife carefully cut out the outlined area This step accomplishes two things First it clears an area for the aileron servo and second it provides an open area between the main wing spars for the dihedral brace 14 Repeat steps 1 through 13 to build the opposite wing half Joining The Wing Panels 15 a Trial fit the two wing halves with the dihedral brace installed bet...

Page 9: ...ue in the brass bearings The outer end of the bearings should be even with the outer end of the blocks 18 a Glue the torque rod block assemblies in place on the wing T E again being very careful not to get any glue in the bearings b Notch the balsa trailing edge just forward of the notches in the torque rod blocks to allow full movement of the torque rods c Sand the top of the basswood blocks to m...

Page 10: ...A will help fill in the weave of the fiberglass resulting in a smoother surface Rub the second coat with your finger protected with plastic wrap keep it moving to smooth out the glue Use a fan to keep the CA fumes away from your face 4 When dry sand lightly to remove any rough spots Try not to sand into the fiberglass tape itself Ailerons 23 Sand the trailing edge of the aileron round and bevel th...

Page 11: ... the engine mounts To avoid any conflict drill a 1 4 dia relief partially through the back of the mounts at each hole 28 Position your engine on the mounts far enough forward for the propeller to clear the fuselage cheeks and mark the engine mounting holes Remove the mounts then drill at the marks with a bit that s just large enough to clear your engine mounting bolts When the time comes to fasten...

Page 12: ...he correct angle 35 a Glue the three 3 16 x1 4 x18 balsa fuselage stringers in place b When dry trim off the front of the stringers flush with the front of HR 36 a Bevel the top edge of the fuselage sides with a sanding block to provide a firm seat for the fuselage top deck when it is installed Notice that the angle between the top deck and the fuselage sides varies along the entire length Don t w...

Page 13: ...to the wing dowel and W 1 wing ribs by working through the opening in the bottom of the wing Be careful not to allow the glue to run down and bond the dowel to F 2 e When dry remove the wing and fill any gaps around the dowel with another application of glue 42 a The 1 4 x3 4 x1 basswood wing hold down blocks key into the notches in the fuselage doubler To accurately fit them temporarily tape or p...

Page 14: ...e outside of the fuselage b Install the die cut Lite Ply stab support so that it is flush with the top of the fuselage sides c When dry sand the Tee Lock tabs on the stab support flush with the fuselage sides 48 a The nylon pushrods must be supported at each former to keep them from flexing under load Use the die cut Lite ply pushrod straps F 3S and F 4S to support the pushrods Notice that the pus...

Page 15: ...both of them at the tips until they match perfectly The tips can be left square or sanded round if you prefer 55 a Sand the pre cut 3 16 balsa fin leading edge round b Sand the trailing edge of the pre cut 3 16 balsa rudder round c Draw a hinge line centered on the leading edge of the rudder Bevel the L E using the hinge line as a guide d Sand a notch in the rudder leading edge to clear the elevat...

Page 16: ...n the wingtips run the covering material around the corner about 1 8 Later when the main top and bottom covering pieces are applied they will overlap the wingtip covering and can be trimmed at the wingtip corners leaving a virtually invisible seam Extend the covering material about 1 8 past the outside edges of the hold down plates again to provide an area for overlap Cover the main portion of the...

Page 17: ...58 Using a No 11 X Acto blade or similar cut slots approximately 1 2 in depth and slightly wider than the hinges Cut eight slots in the stabilizer and eight matching slots in the elevators at the locations shown on the plans 59 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 elevators onto the hinges You ...

Page 18: ...e the stabilizer to the fuselage using Kwik Set epoxy Recheck its alignment and adjust as necessary before the glue dries 66 a Cut away a 3 16 wide strip of material from the center of the stabilizer where the fin is to be glued Epoxy the fin to the top of the stabilizer using a triangle to check its alignment as it dries Make certain that the back edge of the fin is lined up with the back edge of...

Page 19: ...nded that you go through the Pre Flight Checklist in Chapter 7 carefully before attempting to fly Engine And Fuel Tank Installation Engine installation on the FOUR STAR 40 is simply a matter of bolting the engine mounts that were prepared in step 28 to F 1 then bolting your engine to the mounts Finish installing the throttle cable which was partially prepared in step 51 by soldering the connector ...

Page 20: ...ioning Guide to set the ailerons in neutral as shown on the plans When you get to the field don t be surprised if the elevator and rudder are suddenly misaligned Temperature and humidity changes can cause the nylon push rod tubes to expand or contract slightly Use the trim levers on the transmitter to reneutralize the control surfaces and do the final trimming in the air The control surface moveme...

Page 21: ... back increases its sensitivity to control inputs but if carried too far the model can become completely unstable and uncontrollable The balance range shown on the plans is a safe area to use for test flights Don t exceed the rearward limit unless you are a very experienced pilot When landing the FOUR STAR 40 may tend to float a bit more than other models you have flown in the past so be ready to ...

Page 22: ...pm Central Copyright SIG Mfg Co Inc SIG MFG CO INC Montezuma Iowa 50171 0520 LIMIT OF LIABILITY In use of our products Sig Mfg Co s only obligation shall be to replace such quantity of the product proven to be defective User shall determine the suitability of the product for his or her intended use and shall assume all risk and liability in connection therewith ...

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