SPACEWALKER RC61 TAIL ASSEMBLY

Before beginning construction on the tail surfaces, carefully cut out all of the "5", "E", and "R" parts from the 3/8" printed balsa sheet (Sheet #3). A jig saw works best for cutting these out. Cut just outside the lines, leaving all of the lines on the parts. When fitting the parts in the structure, use a sanding block to bring the edges to an exact fit. Pin the plans to the building board and cover them with waxed paper or plastic wrap.

Stabilizer and Elevator
HINGING TIPS
-When assembling each hinge, leave about a 1/16" gap between the head of the pin and the edge of the hinge when you make the bend. After the bend is made and the pin point is clipped, push the pin head up against the side of the hinge. This will move the bend away from the hinge, preventing it from causing a "bind".
-Once you have cut the initial slot in the wood with a knife and widened it slightly with a small saw blade, a thicker saber saw blade can be used to help widen the slot to the proper thickness for the heavy-duty hinges.
-Apply a drop of oil or a bit of vaseline to the center "bulge" of the hinges. This will prevent any glue from bonding at the critical hinge joint. Be sure to keep the flat part of the hinges free of oil.
-A good way to insure that the hinges are soundly glued to the structure is to apply Sig slow-drying epoxy to each hinge slot using a Sig Mini Glue Gun (SH-627). Smear a layer of epoxy on both sides of the hinges and push them into the slots. Wipe away any excess glue before it dries.
-Work with only one control surface at a time. For example, glue the hinges to the stabilizer, allow them to dry, then glue the elevator to the hinges.
NOTE:
Many modelers feel that it is easier to cover the horizontal tail surfaces before they are hinged. If you elect to do this, first test assemble the tail surfaces on their hinges without glue, to insure that a good match between the elevator and stabilizer was obtained during the sanding process. Notice that the tips of the stabilizer leading edge must be trimmed slightly to blend in with the curve of the elevator tips.

53.

Prepare the stabilizer/fin trailing edge by gluing a piece of 1/8"x3/8"x36" spruce to a piece of 3/8"x3/4"x36" balsa. Be sure to keep these parts straight while the glue dries. The spruce laminate increases the strength of the structure and helps to prevent warps from developing. This 36" laminated piece must be used for both the stabilizer trailing edge and the fin trailing edge. There is very little excess, so cut these parts out carefulIy.

54.

  1. Pin the laminated elevator trailing edge in place over the plans.
  2. Cut the stabilizer leading edges from a piece of 3/8"x3/4"x36" balsa. Pin the leading edges in place and glue them together at the center.
  3. Glue in the 3/8" balsa 5-1, 5-2, and 5-3 center sheeting parts.
  4. Add the 3/8" sq. balsa ribs and end pieces.
  5. Glue in the 3/16" x 3/8" balsa diagonal ribs.


55.

  1. When dry, remove the stabilizer from the building board and lightly sand the top and bottom to smooth out the glue joints. Use a sanding block to sand all of the edges round. You may find that a line drawn along the center of all the frame pieces can help in getting a consistently rounded edge.
  2. Trim off the leading edge point as shown on the plans.


56.

  1. Pin the 3/8" sq. x4" spruce elevator joiner in place on the plans.
  2. Cut out the elevator leading edges from 3/8"x3/4" balsa, being sure to notch the right-hand one for the elevator joiner. Glue the elevator leading edges to the elevator joiner and pin them in place.
  3. Add the pre-cut 3/8" basswood control horn mount.
  4. Cut out the elevator tips and trailing edge pieces from 3/8"x3/4" balsa and pin them in place. These parts will be trimmed to shape later.
  5. Glue in all of the "E" parts, E-1 through E-6.
  6. Add the 3/8" sq. balsa ribs and end pieces.
  7. Add the 3/16"x3/8" balsa diagonal ribs.

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57. When dry, remove the elevator from the board and trim it to the correct outline. An easy way to do this is to make a tracing of one elevator half and cut it out. Place the tracing over the elevator, draw around the outline, then sand it down to the line. Repeat for the other half. Lightly sand the top and bottom, and round all the edges as you did with the stabilizer.

58.

Position the heavy-duty elevator control horn on the bottom of the elevator as shown on the plans. Mark the location of the two mounting bolts, then drill the elevator at the marks with a 5/32" drill bit. Countersink the holes slightly on the top of the elevator and install two 4-40 blind nuts. The horn is mounted using two 4-40x3/8" mounting bolts, but not until the elevator has been covered and painted.

59.

Install the hinges in the positions shown on the plans. See "Hinge Assembly" (Plate 2) for more detailed instructions.




Fin And Rudder

The fin and rudder are assembled over the plan in the same manner as the stab and elevators.

60.

  1. Pin the laminated balsa/spruce fin trailing edge in place. Notice that the trailing edge extends to the bottom of the fuselage.
  2. Pin the 3/8"x3/4" balsa fin leading edge in place. Notice that the leading edge extends down below the stabilizer.
  3. Glue the four 3/8" sq. balsa ribs in place.
  4. Add the 3/16"x3/8" balsa diagonal ribs.
  5. When dry, remove the fin from the board and sand the leading edge, top edge, and trailing edge round. Leave the bottom 3/8" sq. balsa rib unsanded so that it can sit against the stabilizer.

61.

  1. Pin the 3/8"x3/4" balsa rudder leading edge to the plan.
  2. Glue R-1 through R-5 in place.
  3. Add the 3/8" sq. balsa ribs and 3/16" x 3/8" balsa diagonal ribs.
  4. When dry, unpin the rudder and sand all of the edges round.


62.

Carefully carve a relief in the bottom of the rudder to accept the rudder horn. Epoxy the horn in place, then drill through the horn and rudder with a 3/32" drill bit. Install a 2-56 x1/2" screw and 2-56 hex nut to anchor the horn to the structure.

63.

Install the rudder hinges in the positions shown on the plan.

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Attaching The Tail Brace Wires

The tail brace wires are a scale feature that will add tremendous strength and rigidity to the entire tail assembly on your model. We recommend that you install all of the wires unless you are specifically building a model of Jesse's prototype. General instructions for installing the wires appear on the plans (Plate 1). The photo shows a typical installation.

Using the plans as a guide, carefully mark the position of each brace wire attach tab on the tail surfaces and fuselage bottom. Drill at the marks with a 3/32" drill bit. Pre-bend the steel tabs to their approximate angle, then fasten them in place using the hardware described on the plans. Apply some Lock-Tite or glue to the nuts to avoid any possibility of them loosening due to engine vibration.

NOTE: The 1/2" long aluminum tubes should be cut in half, making two 1/4" long tubes to clamp the wires.
Steel cable is provided in the kit to serve as tail brace wires. Cut each wire about two or three inches longer than necessary so you have some excess to work with, (Remember to save some of this cable for the rudder control system.) Fasten the wires as described on the plans. What you want are eight wires, each with a slight amount of tension. The actual amount of tension is not too important as long as they are all about the same and the tail surfaces aren't twisted or distorted from their normal position.

FUSELAGE CONSTRUCTION

Before beginning work on the fuselage, carefully cut out the WS-l, WS-2, and WS-3 wing saddle pieces from the 1/4" printed balsa sheets (Sheet #2). As with the printed tail parts, cut just outside the lines with a jigsaw or modeling knife. Use a sanding block to fit the parts exactly to the structure.
Before beginning work on the fuselage, you should decide what engine you plan to install. Since there are so many engines available that can be used on the Spacewalker, it was impossible to design the kit with a standard nose section. See "About the Firewall (F-1) Location" on Plate 4 for more information.

If you must build the model before deciding on an engine, it would be better to build the nose too short than too long. That way, a plywood shim or mounting "box" can be added to the front of the firewall if necessary to position the engine correctly. If the nose is too long, it will have to be sawn off and rebuilt.

Prepare the front fuselage main frame drawing (Plate 4) with the correct nose section for the engine that you plan to use. Cover both the front and aft fuselage main frame drawings with waxed paper or plastic wrap.

64.

  1. Begin construction of the front fuselage main frame by gluing and pinning down the 1/4" sq. spruce pieces along the top, front and bottom.
  2. Glue in the 1/4" sq. balsa uprights.
  3. Glue WS-1 in place.
  4. Fill in the forward two nose sections using a 1/4"x3"x12" balsa sheet. This solidifies the front end which helps to absorb engine vibration.

65.

Build a second front fuselage main frame exactly as the first. When dry, pin the frames together and lightly even up the edges with a sanding block. Sand both sides of each frame to remove any rough spots or glue "bumps".

66.

Repeat the process to construct two aft fuselage main frames.

67.

  1. Glue the die-cut lite-ply PS-1 pieces to the front fuselage main frames. Be sure to make one right side and one left side! The PS-1 pieces were cut extra long to accommodate any firewall position. Trim and sand the lite-ply even with the main frames.
  2. Glue the PS-2 pieces to the rear fuselage main frames, again being certain to make a left and a right.

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68.

  1. Pin the front fuselage main frames upside-down over the fuselage top view (Plate 1). The plywood side pieces (PS-1) should be facing inward. Make certain the sides are vertical and use temporary braces (marked with a "T" in the photo) to hold them in position.
  2. Carefully cut and fit the 1/4" sq. balsa crossbraces and glue them in place. There are six crossbraces on the top of the fuselage (next to the plan) and four on the bottom. Notice that the crossbrace at the front of the wing (marked with an "X" in the photo) should be positioned 1/8" forward of the wing leading edge to make room for the PW plywood pieces to be installed later. Check the squareness of the fuselage several times during this step. When dry, remove the temporary braces.






69.

  1. Taper the ends of the aft fuselage main frames where they join at the rear.
  2. Pin the aft fuselage main frames upside-down, plywood side pieces facing inwards, on the fuselage top view (Plate 2) and glue them together at the rear. Use a triangle and temporary braces to hold the frames square as you did with the front fuselage main frame.
  3. Glue the 1/4" sq. balsa crossbraces between the frames (Seven on top, seven on the bottom).

70.

  1. Tape together the two fuselage top views using a long straightedge to make certain the centerline is perfectly straight from the front to the back.
  2. Sand the front end of the aft fuselage section with a large sanding block so that it fits flat against the front fuselage section. Check the alignment of the two fuselage sections over the top view drawing. When satisfied with the fit, epoxy the aft section to the front fuselage section and allow to dry.

71.

  1. Glue the die-cut lite-ply part PT-2 to the top of the fuselage so that its front edge covers only half of the crossbrace located just aft of F-2.
  2. If your engine mount uses bolts that are inserted from the rear of the firewall, you will need to cut an access hole in PT-I so that you can get to the top two bolts. Glue PT-I to the fuselage just ahead of PT-2. Trim off any excess.
  3. Glue PB-I to the fuselage bottom with the rear edge even with the front edge of the balsa crossbrace. Trim off the excess at the front so that it is flush with the front face of the fuselage. Sand the rear edge of PB-I at the same angle as the fuselage bottom.

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72.
  1. Construct the firewall by gluing the two 5/32" plywood F-I formers together with Sig Kwik-Set epoxy. Use a heavy weight to hold the two pieces perfectly flat while drying.
  2. When dry, use "Cross Section at F-I" drawing (Plate 1) to draw the vertical centerline and thrust line on the firewall.
  3. Carefully position your engine and engine mount on the firewall and mark the location of the mounting bolts. Drill the firewall at the marks. If you are using blind nuts, they should be installed now and glued firmly in place.






NOTE: The engine shown being fitted to the photo model is a Zenoah G-38 with a B & B Specialties engine mount and muffler. This mount uses four bolts installed from behind the firewall; therefore, blind nuts were not necessary. The two upper bolts are easily accessed through the opening cut into the plywood top, PT-I, in Step 71.

73.

  1. Epoxy the firewall in place on the fuselage. The thrust line should be level with the top of the spruce longerons and balsa crossbrace, NOT THE TOP OF PT-I!
  2. Reinforce the firewall/fuselage joint with two lengths of 1" triangle stock, one on each side. (See Photo 88.)
  3. Carve and sand the bottom edge of the firewall at the same angle as PB-l.

74.

  1. Glue the lite-ply formers F-4 and F-5 together.
  2. When dry, glue the F-4/F-5 assembly to PT-2 in the position shown on the plan. Use a triangle to square with PT-2.
  3. Glue formers F-2 and F-3 to the top of the fuselage in the positions shown on the plans.

75.

The position of F-IA may have to be adjusted vertically on the back of the firewall so that the stringers will be perfectly straight from front to rear. Trial fit several stringers and trim F-IA as necessary to make them straight. When satisfied with the fit, glue F-IA to the back of the firewall.

76.

Glue five 1/4" sq. balsa stringers in place between formers F-IA and F-3. Trim the stringers flush with the back edge of F-3.

77.

Protect the balsa stringers and the edge of F-2 with masking tape, then use a long sanding block to bevel the top edge of the firewall until it is flush with the outer surface of the stringers.

78.

  1. Three sheets of 1/8"x4"x21" balsa are provided for the front deck sheeting. Start with a full-width sheet in the center. It should just cover about half of the two stringers on either side. The rear edge of the sheeting should just cover F-4, leaving F-5 exposed for the rear stringers and apron pieces to be installed later. It will probably be necessary to soak the outer surface of the balsa with water or alcohol to help it bend around the formers. While wet, gently form the balsa with your fingers to about the right contour, then glue it in place, using tape or pins to hold it until dry.
  2. Prepare the sheeting for the rest of the front deck by soaking and forming as you did before. When formed to about the correct shape, hold it in place and mark the bottom edge for trimming. It should be trimmed so that it overlaps the edge of PT-1and PT-2, even with the top edge of the top longeron. Use an easy-to-sand glue, such as Sig Bond, to glue the sheeting in place. Notice that the sheeting tends to bow outwards between formers F-3 and F-4, but most of this is cut out anyway for the cockpit opening.
  3. When the sheeting has dried, trim off the excess at the front flush with the firewall. Use a long sanding block to sand the sheeting smooth, being careful not to sand away too much material.

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tr>
79. Use scissors to remove the "Cockpit Cutout Pattern" from the plans (Plate 1). Follow the directions printed on the pattern to cut out the cockpit opening.

80.

Glue the die-cut lite-ply PF pieces to the sides of the fuselage as shown on the plan. Trim off the front edges flush with the firewall and PB-1.


81.


  1. Position the lite-ply formers F-6 through F-10 over their respective cross-sectional drawings on the plans (Plate 2). Mark the positions of the top stringers on the formers.
  2. Glue formers F-6 through F-lO to the fuselage in their correct positions as shown on the plans. Notice that F-10 is positioned even with the rear edge of the balsa crossbrace. The other formers are centered on their crossbraces. Also be certain that each former is centered left and right on the fuselage.








82.

Glue the five 1/8"x3/8"x36" balsa top stringers to the former F-5 through F-10. The center stringer should be left extra long at the rear so that it can be trimmed to match the fin later. The two stringers on either side of the center stringer should be rounded at the rear as shown on the plans. The two outboard stringers are cut off flush with F-10. All of the stringers should be perfectly straight from front to rear. Strengthen each stringer-to-former joint with a small fillet of glue.

83.

Add the die-cut balsa apron pieces between the stringers. The apron pieces will need to be trimmed on each side for a perfect fit.

84.

  1. Glue the die-cut lite-ply TM tab mounts to the bottom longerons as shown on the plans.
  2. Add the 1/8"x1/4" balsa fill strips to the bottom of the bottom longerons. Notice that this fill strip ends at the rear-most crossbrace to allow room for the tailwheel mount, TWM.
  3. Glue 1/8"x3/8" balsa fill strips to the sides of the bottom longerons.
  4. Glue 1/8"x1/4" balsa fill strips to the sides of the top longerons on the aft fuselage section.
  5. The 3/16"x1/4" balsa fill strips should now be glued to the side of the top longerons on the front fuselage section.
  6. Add the small 1/8"x1/4" balsa fill strips on the side of the fuselage just forward of the wing leading edge.
  7. Add the 1/8"x1/4" balsa fill strips to the aft fuselage at the wing saddle.
  8. Glue the die-cut balsa FS-1 and FS-2 pieces to the fuselage sides.

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Fitting The Wing To The Fuselage

NOTE: The wing center section, completed through Step 38, is needed for the following steps.

85.

The wing saddle area must be carved at an angle for the wing to seat properly on the fuselage. Use the plywood side pieces PS-1 and PS-2 to act as guides which should not be altered. Sand the balsa until you reach the edge of the plywood, then stop. Use the Wing Saddle Carving Guide (Plate 2) to check your progress as you work. If you should overcarve, do not fix it by trying to reshape the bottom (which could cause a change in the wing incidence). Instead, fill the gap with model putty. Lay the wing center section in the wing saddle and check the fit.

86.

  1. The remaining two W-1A sub-ribs are positioned in the wing center section so that they line up with the fuselage sides. With the center section positioned accurately on the fuselage, lay a straightedge along the fill strip on the fuselage side so that it extends over the wing. Now mark the bottom leading edge sheeting with a soft lead pencil.
  2. Remove the center section from the fuselage and carefully cut away the bottom leading edge sheeting at the line. Don't cut the spar!
  3. Trial fit the W-1A sub-ribs and trim as necessary. Glue the subribs into the center section so that they rest against the cut edge of the leading edge sheeting.

87.

Two pieces of 5/8"x3-1/4"x1" balsa are provided for landing gear support blocks. These are installed against the back of the leading edge, with the grain running vertically. Notice that the top of the support blocks must be sanded to the contour of the top leading edge sheeting. The bottom of the blocks should be flush with the cutouts on the W-1A sub-ribs. When satisfied with the fit, firmly glue the blocks in place. Look ahead to photo 89-90 to see the blocks glued in place.

88.

  1. Glue the 1/8" plywood PW wing hold-down straps to the inside of the fuselage. The top end of PW butts against the bottom of the 1/4" sq. balsa crossbrace.
  2. Brace the back side of PW to PS-1 with 3/4" triangle stock. When dry, carve the triangle stock to match the wing saddle.




89.

  1. Use the "Cross Section at F-2" (Plate 1) to locate and mark the position of the wing hold-down dowel on PW.
  2. Drill PW at the mark with a 1/8" pilot drill, then follow up with a 5/16" drill.

90.

  1. Sharpen one end of the 5/16" dia. x1-1/2" long wing hold-down dowels, being sure to keep the point centered. Push the dowels into the PW pieces from the front so that just the points stick out the backside. (It may seem that the dowels go into the holes awfully hard, but they'll loosen up after they've been pushed in and out a few times.)
  2. Carefully slide the wing into position, pushing the sharp dowel points into the wing leading edge.
  3. Remove the wing and drill two 5/16" dia. holes through the wing leading edge at the punch marks.

91.

  1. Remove the dowels from the PW wing hold-down straps. Reinsert the dowels from the other side through pieces of wax paper. Only push the dowels in 5/16" - leave most of the dowel length sticking out.
  2. Trial fit the wing in position, sliding it onto the dowels. Check to see that the wing still fits the fuselage. If not, slowly enlarge the holes in the wing leading edge until it fits properly. When satisfied with the fit, coat the inside of the holes in the wing with epoxy and slide it back in place on the fuselage. When dry, carefully remove the wing and fill any small gaps around the dowels at the wing leading edge with another application of glue.

92.

  1. The 3/4"x3/4"x3" basswood wing mounting blocks must be beveled on the side so that they fit flat against the fuselage side (PS-2) and the top surface of the wing. Check their fit by installing the wing on the fuselage and holding the block in place. When they fit properly, epoxy the wing mounting blocks in place.
  2. Glue lengths of 3/4" triangle stock to the top and front of the wing mounting blocks.

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93.
  1. Tape or pin the wing to the fuselage, making sure that it is in perfect alignment. Carefully and accurately mark the position of the wing hold-down bolts on the bottom surface of the wing. Visually confirm that a hole drilled at the marks will pass through the approximate center of the wing mounting blocks.
  2. Drill through the wing and the wing mounting blocks at the same time with a #7 (or 13/64") drill bit. Keep the drill perpendicular to the bottom surface of the wing so the heads of the nylon bolts will seat flush against the wing.
  3. Remove the wing and tap the wing mounting blocks with a 1/4-20 tap. You can apply a few drops of thin C/A to the holes to strengthen the threads.
  4. Redrill the holes in the wing with a 1/4" drill bit to pass the nylon wing bolts.




Completing The Fuselage

94.

  1. With the wing bolted in place, glue F-6A to the fuselage, just behind the trailing edge. You will have to cut away a small portion of the fill strips to make room for F-6A.
  2. Cut and shape the bottom stringer from a piece of 1/8"x3/8"x36" spruce. Glue the stringer along the center of the fuselage bottom with its front end against the backside of F-6A.
  3. Trim the die-cut lite-ply PB-2 reinforcements to fit between the bottom stringer and the 1/8"x1/4" balsa fill strips. The outer ends of the reinforcements should rest on the bottom edge of PS-2. Sand the wing trailing edge and fuselage bottom for a good match to each other.





95.
  1. Mark the positions of the side stringers on the fuselage main frames. Cut and shape the side stringers from 1/8"x3/8"x36" spruce, then glue them in place on the fuselage.
  2. Use a sanding block with one end covered with heavy paper to sand the fill strips to the shape shown in the fuselage cross sections (Plates 1 and 2). The paper protects the spruce stringers from being taken down while sanding the fill strips. Use the same technique to sand the fill strips on the front fuselage section, including FS-1 and FS-2. Complete the shaping by sanding the corners round on the fuselage bottom.
BUILDER'S TIP:
While there is still easy access through the bottom, now is the time to install the fuel tank, throttle pushrod, etc. The fuel tank should be mounted with its' centerline even with or slightly below the centerline of the engine's carburetor. Materials for mounting the tank are not furnished specifically, but there should be plenty of scrap that can be used. The tank supports should hold the tank in its proper position but should also allow it to be pulled out easily if necessary. See "TIPS ON TANKS" , and "THROTTLE HOOKUP".
NOTE: The wing center section, completed through Step 40 is required for the following instruction.

96.

  1. Glue together the two 3/8"x4"x4-1/2" balsa bottom sheets to form a piece that is 8"x4-1/2".
  2. With the wing bolted to the fuselage, use a sanding block to bevel the back edge of the bottom sheet so that it sits flush against the landing gear mount in the wing leading edge. When satisfied glue the bottom sheet to the fuselage.
  3. When dry, sand the bottom sheet to the contours shown in the "Cross Section at F-l" and "Cross Section at F-2" drawings (Plate 1). The bottom sheeting should now blend smoothly into the landing gear mount.

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97.
  1. Glue the die-cut lite-ply G-l pushrod exit guide to the left side of the fuselage as shown on the plan. The outer edge of G-l should be flush with the outer edge of the fuselage main frame.
  2. Glue scrap pieces of 1/8"x3/8"x2" balsa in place on each fuselage side to serve as cable exit guides.
  3. When dry, drill the cable exit guides with a 9/64" drill to accept the nylon tubing guides. The holes should be drilled at a shallow angle so that the rudder cables will exit the side of the fuselage in the direction of their attach point on the rudder control horn. Cut two 3" lengths of nylon tubing from the piece provided in the kit and glue them into each of the drill holes. Cut the tubes off flush with the cable exit guides.
TIPS ON TANKS
The 24 oz. fuel tank shown on the plans will provide sufficient run time for most of the engines that are suitable for the Spacewalker, although there is plenty of room for a larger tank if desired. The plans show a slant type, but other styles may be used as well. The simplest, most trouble-free tank set-up to use in the Spacewalker is normal suction feed with two vents, as shown in the diagram below. Both vent tubes should curve upwards inside the tank. The clunk line on the fuel feed tube must swing freely without hitting the back of the tank. Remember to use a fuel tank stopper and fuel lines that are compatible with the type of fuel to be used.
For best results, the fuel tank should be positioned so that its centerline is even with, to 1/4" below, the needle valve on the engine. It can be mounted with scrap balsa supports to hold it in place. Should the need ever arise to remove the tank for servicing, simply break away the balsa supports. You can seal around the hole in the firewall where the fuel lines come through with silicone rubber sealer to prevent exhaust oil from leaking inside the fuselage. Run fuel tubing from the fuel feed line to the carburetor. Two more lengths of tubing run from the vent tubes to the bottom opening in the cowl. To fuel the aircraft, simply pump fuel into either of the vent lines until it runs out the other. Plug one of the vents with a short bolt to keep the fuel from siphoning out. It's not necessary to remove the feed line from the carburetor to refuel. To defuel, turn the fuselage upside-down and pump any remaining fuel out through one of the vent lines. If your engine's muffler is equipped with a pressure tap, you can make use of it to help provide a more reliable fuel feed. To do this, connect one of the vent lines to the pressure tap. The other vent line must still be plugged with a bolt to operate properly. To refuel, remove the vent line from the pressure tap and remove the bolt from the other line, then fill the tank as you normally would.


BUILDER'S TIP:
The task of drilling the holes for the rudder cable guide tubes at the shallow angle can be made easier, as follows. Use a small drill bit (1/16" dia.) or a sharpened piece of music wire to first make a pilot hole. The 9/64" drill bit should then follow the pilot hole with no problem.

Attaching The Tail Surfaces And Tailwheel

NOTE: Many modelers prefer to cover their tail surfaces before attaching them to the fuselage. If you choose to do this, be certain that all the hinge slots are cut and the control surfaces move freely with the hinges temporarily in place.

98.

  1. With the wing bolted in place, position the stabilizer on the fuselage and check its alignment carefully. Be certain it is square with the fuselage by viewing it from the top and rear. When you are satisfied with its position, make small marks on the fuselage and stabilizer so that it can be returned to the same position.
  2. If you have already covered the stabilizer, the covering material will have to be cut away (use a sharp razor blade) where the stab rests on the fuselage, so that you will have a strong wood-to-wood glue joint. Epoxy the stabilizer to the fuselage, lining up the marks that you made earlier. Recheckthe alignment of the stabilizer as the glue dries, making adjustments as necessary.


NOTE: The elevator must be permanently hinged to the stabilizer before the fin is attached.

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99.
  1. Trial fit the fin on top of the stab. You will have to trim the center top stringer to fit against the fin leading edge, and the fin trailing edge will need a small cutout to clear the elevator joiner. The extended tail post on the fin should be in good contact with the fuselage end. If the stabilizer has been covered, cut away the covering material where the fin attaches.
  2. Epoxy the fin to the top of the stabilizer and the rear of the fuselage, using a triangle to make certain it is vertical. Also, make sure that the fin is not offset to one side or the other by viewing it from above.

100.

  1. Brace the bottom of the fin leading edge to the bottom of the stabilizer using small lengths of 3/8" triangle stock. See the "Cross Section at Base of Fin Leading Edge" (Plate 2) for more information.
  2. Install R-6 on the front of the fin. When dry, sand the edge round.
  3. Add the 1/8"x1/4" balsa fabric attach strips to each side of the fin. The bottom edge must be beveled slightly to blend in with the top stringers at the front. The rear edge of the fabric attach strips should blend smoothly into the sides of the fin at the back.
  4. Glue small scraps of 1/8"x3/8" balsa between the outermost top stringers and the balsa fill strips, just forward of the stabilizer leading edge. These scraps provide a place for the covering material to attach in this area.
  5. Blend the fin post into the fuselage sides using scraps of balsa glued to each side of the fin. The balsa scraps should be sanded flush with the fill strips at the front and tapered down to nothing at the back edge of the fin post.

101.

  1. Position the formed tailwheel leafspring on the die-cut lite-ply TWM tailwheel mount and mark the location of the mounting bolts. Drill TWM at the marks with a 3/16" drill bit. Mount the leafspring using the 10-32 x 3/4" machine screws and the square nuts provided.
  2. Epoxy the nuts firmly in place being careful not to get any glue on the machine screws. When dry, remove the leafspring.
  3. Trim away the balsa fill strips on the bottom longeron in the area where the tailwheel mount fastens to the fuselage. The spruce longerons will have to be relieved slightly to allow room for the square nuts. Drill a relief area into the longerons to clear the rear mounting bolt. TWM should now fit flat against the bottom of the fuselage and fin.
  4. Epoxy TWM in place, being careful not to get any glue in the threads of the square nuts.





NOTE: The tailwheel steering springs supplied in the kit must be stretched to their proper length before they are installed. Grab each end of a spring with pliers and pull until you feel it "give". Don't overstretch it! It's easier to lengthen it a little more than to shorten it. With no tension on them, the pre-stretched springs should be about two inches long, as shown in the drawing.

LANDING GEAR CONSTRUCTION

NOTE: The completed wing center section is needed before the landing gear can be assembled.

HELPFUL HINT:
Under the stress of a painfully hard landing, the 1/8" bottom shock strut wire will want very much to part company with the solder joints that bind it. Now, if those solder joints are flawless, the shock strut wire will surely be held fast. But, since very few of us are flawless, chances are good that our solder joints will be somewhat less than perfect. To help keep the ends of that shock strut wire firmly entrenched between the main I.g. wires, we suggest that you file or grind small notches into the shock strut wire as illustrated here. Now solder will flow into the notches and "lock" the shock strut in place, thus avoiding the unhappy possiblity described earlier!

102.

Position the 3/16" front main I.g.wire and the 3/16" rear main I.g. wire in the grooved landing gear mounts in the wing center section. The rear landing gear block will have to be notched on both sides to allow the rear wire to swing forward.

.

103. Hold the legs of the 3/16" main I.g. wires together and add the 1/8" bottom shock strut wire between them. Rebend the wires slightly, if necessary, to get all of the wires to line up properly. Cyanoacrylate adhesive can be used to hold the wires together temporarily. When you have them aligned, bind them tightly together with copper wire then solder securely. Use plenty of heat and soldering paste so that the solder will flow completely around and through the bindings. Drape a cloth over the center section to protect it from dripping solder or paste.

104.

Remove the wire gear from the wing, then bind and solder the, 1/8" dia. top shock strut wire in place. After all of the joints are cool, file and sand them to smooth out any prominent bulges in the bindings. Clean all joints with dope thinner or other suitable solvent.

105.

Cut a 1" long piece of scrap 1/16" dia. music wire (or similar) from leftover pieces you undoubtably have in your workshop. Form it into a shallow "V", then bind and solder it to the top shock strut wire. This serves as a hook for wrapping rubber bands around both shock strut wires to act as a shock absorber.


106.


Refit the landing gear to the wing. Position the four large nylon landing gear straps over the wires, as far outboard on each side as practical. (Positioning the straps this way will help to prevent the gear from shifting side-to-side during rough landings.) Mark the hole locations for the straps, then pilot drill the landing gear mounts and thread in the screws.


107.

  1. A single sheet of 3/16"x4"x12" balsa is provided for fairing in the sides of the landing gear. Cut out pieces to fit between the 3/16" wires, noting the grain direction shown on the plans. Epoxy the fairings in place and allow to dry.
  2. Heavy-weight fiberglass cloth is provided for reinforcing the landing gear and the fairings. Cover one side at a time using slow-drying epoxy to apply. Lap the cloth past the edges of the wood, completely around the 3/16" wires. When dry, sand smooth.


COMPLETING THE MODEL

Wheel Pants


The directions given below are for a single wheel pant. Of course, you must make two wheel pant assemblies, a left and a right.

108.

  1. Clean and sand the inside surface of the pant where the diecut 1/16" plywood mounting plate will attach. Epoxy the plate in place as shown on the plans (Plate 4).
  2. Carefully locate and mark the position of the axle on the wheel pant using the plans as a guide. Drill through the pant and mounting plate with a 3/16" drill bit.
  3. Install a 6-32 x 3/8" socket-head set screw into one of the molded nylon wheel pant mounts. Temporarily hold it on the outside of the pant and mark the location of the two outer holes. Drill through the pant at the marks with a 3/32" drill bit. Permanently fasten the wheel pant mount to the inside of the wheel pant with two #4 x 3/8" sheet metal screws.
  4. You must grind or file a shallow flat spot on the wire landing gear where the wheel pant mount's set screw makes contact. The position of this flat spot will also determine the position of the wheel pant. The flat spot may have to be slightly re-ground several times before the wheel pant assumes the correct angle. The centerline of the pant should generally be parallel with the fuselage top longeron, and both pants should be parallel to each other.