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Last Updated: January 10, 2008 - 09:28:40 PM

HET-RC - F-16 Falcon EDF
By Carl Tulanko
February 15, 2007 - 11:53:25 PM

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01 - The F-16 as it arrives well packed from Markos at Warbirds-RC

02 - The model is double boxed and all parts are wrapped for protection

03 - The HET-RC F-16 Falcon ARF Minifan 480 Jet out of the box

04 - The major components of the model. It is very similar to the HET-RC FA-18 in construction and covering

05 - Front view of cockpit area. The glass work is very well done

06 - Rear view showing pre-installed Fiberglass Intake and formers

07 - Construction: Sand the wing saddle on the fuselage for good glue purchase

08 - Five Minute Epoxy is applied in the wing spar hole using a cut down mixing stick to fit the slot

09 - Next, insert a wing spar until it bottoms out in the slot

10 - Spar shown installed

11 - Clean up excess epoxy with some paper towels and denatured alcohol

12 - Spar installation shown completed

13 - There is a left and right wing. The side with less curve is the bottom, so mark them "left" and "right"

14 - The wing is placed over the spar and adjusted so it is centered in the rear and the front of the fuselage. This will adjust the spar to the correct position. Carefully remove the wing and let the spar glue set

15 - The wing shown installed and flush in the front of the fuselage shows a gap at the rear. This will be filled with Epoxy when the wing is mounted

16 - A 1/8" drill bit is used to make some holes in the fuselage. This will allow the epoxy to create "rivots" inside the wing saddle for a stronger joint. Lightly sand after drilling to remove burrs

17 - Fifteen minute Epoxy is applied to the wing root

18 - Fifteen minute Epoxy is applied to the wing root.

19 - The wing is set in place. If you fiberglassed your wing, masking tape is used to keep excess epoxy from adhering to the finished surface. Make sure the wing is centered and the bottom of the wing is flush with the root molding of the fuselage. Keeping the bottom of the wing flush with the bottom of the fuselage will insure correct incidence without any twist for the wing position.

20 - Denatured alcohol is used to remove the excess epoxy

21 - The front of the wing is centered and held in place with masking tape. The rear is centered and held in place with a clamp and left to set

22 - The other wing saddle is sanded for better glue purchase. A small piece of 60 grit sandpaper makes quick work of it, but be careful not to oversand

23 - Epoxy is applied to the spar slot with a cut back mixing stick

24 - Epoxy is applied to the spar and the wing spar is installed until it bottoms out in the slot

25 - Excess glue is cleaned up with denatured alcohol and a paper towel

26 - Spar is installed

27 - Wing is placed in position and centered in the front and back to correctly position the spar, then it is carefully removed before the epoxy sets, then the spar is drilled for rivot holes

28 - Epoxy is applied to the wing root

29 - Next epoxy is applied to the fuselage wing saddle and spar

30 - The wing is installed on the saddle and centered. Excess epoxy is removed with denatured alcohol and a paper towel. Then tape is used to keep the front of the wing centered and the bottom of the wing flush to the fuselage root while a clamp keeps the rear centered until the epoxy sets

31 - Epoxy is applied to the joint as a fillet. A toothpick is used to apply it and the tape was place on the surfaces to catch the overflow

32 - The excess epoxy is wiped off and overflow lands on the tape

33 - The tape is removed, revealing a clean joint. Repeat and do the same on the other side of the model

34 - Wings are shown installed on the fuselage

35 - Front view of wing installation shows wings with a couple of degrees on anhedral. This was due to the design of the fuselage

36 - The vertical stabilizer area of the fuselage is taped off so sandpaper does not mar the finish

37 - Sand the sides of the saddle with 80-100 grit sandpaper. Be very careful as to not oversand as you could cut through the glass

38 - Side view shows edges sanded and ready for epoxy

39 - The top outside edges were sanded so any excess glue would adhere well and form an internal fillet. While it is not necessary, the entire top of the saddle area was sanded in the pic

40 - Stab area sanded. Be careful to not oversand...if you do, simply apply a coat of epoxy on the inside area of the fuselage to strengthen

41 - Marks were made in order to cut two 1 1/2" long slots in the vertical stab area that are used for both cooling and the receiver antenna

42 - A Dremel with a stone cutting wheel was used to open the slots

43 - A hobby knife is used to clean the corners and remove large burrs

44 - Some 400 grit sandpaper is used to smooth the edges inside and out

45 - The two slots are shown finished. This completes the Vertical Stab pre-assembly

46 - The wood pieces that are needed for Taileron assembly. Make sure you make two opposite/mirrored trays, one for the left and one for the right. The side plates are labeled S for Short and L for Long with the long side facing the front of the fuselage when installed

47 - The two ends of both servo trays were lightly beveled with 400 grit so they could fit in the slots of the side plates

48 - Use a ruler to mark center on the servo tray

49 - Mark both trays with a center line for your servos

50 - The HS65 servos are a perfect fit and were inserted in their tray to mark for drilling. The was some play in the tray, so the servo was pushed flush against the left side, then holes were drawn on both ends. It was then pushed flush to the right side and marks were made again

51 - You can see the two marks made at each end. Draw a line between them for a perfect center

52 - Use a punch to mark where the holes need to be made

53 - Use thin CA to coat each mounting hole area on both sides of the tray. This will prevent cracking and splintering when drilled

54 - The tray is lightly sanded to smooth out the CA glue area

55 - You need a hobby drill smaller than the standard US 1/16" because the servo mounting screws are so small, so I found that a medium hobby push pin would work. Use a hammer and carefully drive it through the tray like a nail, being careful to keep it straight. Remove the pin and insert it in the back side of the tray to open the hole a bit

56 - Photo shows the pin driven through the plate

57 - Servo mounting screws are installed to "cut" threads in the wood

58 - Temporarily install the servo...the screws should match up with the holes and the servo should be centered in the tray

59 - Insert a tray into a side plate. Note that the thin side of the tray faces upward toward the angled side of the plate. Do not push in all the way

60 - Install the other end of a tray into a plate, with the angled side of the plate facing the thin side of the tray. Be sure to use a short plate on one end and a long plate on the other end

61 - Mix some 5 minute epoxy and use a toothpick to roll it into the joint at both ends

62 - Squeeze the plates in place and flush

63 - Remove the excess epoxy that could prevent the servos from sitting flush

64 - Removing the eopxy leaves a very fine fillet

65 - Square up the tray before the epoxy sets

66 - Build the other tray and make sure you make two opposite "mirrored" trays

67 - Once both trays are completed, add a fillet of epoxy to the rear for added strength

68 - Remove the excess epoxy so a nice fillet is made

69 - Servo Tray construction completed and showing fillets at rear side

70 - From the top of the fuselage- The stab block and servo tray are shown near the positions where they will be installed in the fuselage. Note that the block tapers rearward and that the tray has the "Shorter" side to the rear with the thin part of the tray pointing to the top side of the fuselage

71 - The position for the Horizontal Stab rods is 62mm from the rear

72 - When first installed inside the fuselage, the blocks were set too far back and not centered over the mark

73 - A piece of 1/32" ply was cut as a shim to make the block thicker

74 - The shim is epoxied to the bottom of the block

75 - With the addition of the shim, the block is inserted and the photo shows where it now would sit inside the fuselage

76 - The second block shim is added using 5 minute epoxy

77 - Lightly sand the edges to even out the shim with the block sides

78 - A Warning...the manufacturing process left some strands of fiberglass that were sharp as needles and located where the pencil is pointing. If you have these, carefully break them off inside so you do not get cut

79 - A mark is made on the outside of the fuselage at 62mm

80 - A second horizontal mark is made at the center of the fuselage

81 - A 1/8" Drill is used to open the holes at the crosshairs. You may want to use a small bit to make a starter hole first

82 - Masking tape is used to wrap around the block so it can be removed easily later

83 - The block is temporarily installed in the fuselage

84 - Keeping the drill square, make a small mark on the ply inside but do not drill through

85 - The drill mark is shown centered in the block

86 - The other block is installed and marked the same way. Use the masking tape tab to easily remove the block once it is marked

87 - A drill press is used to drill through the block and keep the hole square

88 - A Hinge drilling jig can also be used to drill a square hole

89 - If you do not have a drill press or hinge jig, the the hole can be carefully drilled by hand. Do a little at a time making sure the bit stays square both horizontally and vertically

90 - Trial fit the Elevon Rod and use the drill to open the hole if necessary so the rod moves in and with little effort

91 - Install the block in the fuselage with the angled side toward the top. Do not glue the block in place yet

92 - Make sure the hole is aligned and centered on the markers

93 - Temorarily install a Elevon rod to check the angle

94 - Rod shown in correct position, perpendicular to the fuselage where it exits. Note that the fuselage is molded to include a downward angle on the rod when compared to the wing...this is normal

95 - Two 1/8" wheel collars are required to retain the horizontal stabs. You may have to purchase a set as they were not in the kit

96 - Apply some blue Loktite on the setscrew for the wheel collar

97 - Install the setscrew in the wheel collar

98 - The Horizontal Stabs may need to be ironed to remove wrinkles

99 - The wheel collar is shown installed where it is used to mount the stab

100 - The wheel collar deforms the top of the monokote

101 - the first 1/2" of the Horizontal Stab rod is roughed up with 60 grit

102 - Install the rod in the horizontal stab and lock it in place with the wheel collar. Make sure that the rod extends past the collar and butts against the left wall as shown. Also, note that the side of the rod that was sanded is shown to the right and will be glued into the fuselage block

103 - Apply epoxy inside the hole with a toothpick

104 - Apply epoxy to the top and bottom of the block

105 - Install the block in the fuselage

106 - Install the Horizontal stab into the inner block hole until the root butts against the side of the fuselage. This will keep the block aligned inside. Put your finger inside the fuselage and make sure the block is settled in its location. Hold the stab tight in place with masking tape

107 - Check stab position from the rear to make sure the angle is aligned with the fuselage trailing tip

108 - Epoxy is applied with a toothpick to the second block hole

109 - Epoxy is applied to the top and bottom of the block, then it is installed

110 - Horizontal Stab is installed through the hole and into the block

111 - Masking tape is used to hold the stab flush to the fuselage side. Check your rear angle as you did with the first stab and make sure it aligns with the fuselage trailing edge

112 - Horizontal Stabs shown installed and in place

113 - The stabs have a slight downward angle from the rear, which should be even on both sides

114 - Use a hex wrench to loosen the retaining wheel collar

115 - Remove the stab and wing collar from the fuselage

116 - Horizontal Stab rod installation completed

117 - The fuselage halves were assembled using what appears to be Aeropoxy, as shown by the arrow. This will prevent the servo trays from seating all the way into the fuselage area. It cannot be easily reached to be sanded

118 - Masking tape is applied to the side of the fuselage area and marked for servo cutout

119 - A Dremel with a stone wheel is used to cut out the opening

120 - Opening is shown rough cut. It was very difficult to cut through the Aeropoxy ridge inside. I used a pair of 90 degree long nosed pliers to break through