Flat Foamie Series

Wigens Z-250 Build Instructions

Leaving the parts in sheet B, cut the small tabs free in the spar slot and using Foam-Tac, glue the medium length piece of flat carbon fiber into the slot in the elevator (B5) from the bottom so any excess glue doesn't squeeze out on the top paint and set aside to dry.
Remove the fuselage top (A4 and A5) and bottom (A1 and A2) pieces from sheet A and glue the angled ends together with Foam-Tac and set them aside to dry. Set aside the foam containing the 8 gussets (A3) for use later.
Optional: If you are going to be adding the optional landing gear to the plane, now is a good time to glue the plywood mounting plate to the Fuselage Bottom (A1/A2) subassembly. Carefully match the holes in the plates with the holes in the foam. You might find it helpful to use the screws through the mounting holes to give you the best alignment.
Remove the Left Wing (C1) and Left Aileron (C2) from sheet C. Place the wing top side down on your cutting surface and place your ruler back from the edge (use a scrap of foam for the proper spacing) and cut the bevel on the inner portion of the wing. The outer section doesn't get beveled as it's for the aileron counterbalance to move. Make the same bevel on the matching aileron (C2) edge. Be careful not to throw away the wheel pant (C3) to be used later.
With the top surface of the Left Wing (C1) and Aileron (C2) held together, line up the bevels just cut so the points are together and the ends match. Put a very small bead of Foam-Tac along the point of the bevel and either with a finger tip or scrap of foam, spread it in a fine film around the point for the length of the bevel. Take the wing and aileron and place them on a flat surface top side up and squish the points together and carefully align the joint so there is good contact. Set this aside to dry.
Following the same procedure, bevel and hinge the Right Wing (D1) and Aileron (D2)
Remove the stabilizer (B3) and the elevator (B5) from the B sheet and bevel and glue the hinges using the same procedure as the wings/ailerons above.
Remove the Rudder (B2) from the sheet and placing the top counterbalance towards the left (as shown), bevel the hinge area.
Taking the fuselage subassemblies(A1/A2 and A4/A5) joined above and cut the rudder hinge bevel, using the rudder from above to verify the correct orientation. Do NOT hinge the rudder at this time (it's simply easiest to cut the bevels now).
Taking the wing subassemblies (C1/C2 and D1/D2), remove the tabs in the precut wing spar slot. Spreading Foam-Tac on the joint at the root of the wings, glue the two wing halves together at the center. Place the wing assembly top side down on a flat surface large enough for the entire plane outline and spread Foam-Tac on both sides of the longest wing spar and insert it into the slot from the bottom. Doing it from the bottom will make any excess glue not mar the top wing paint. Squeeze the spar joint together to make sure you get good contact between the carbon spar and the foam and then wipe off any excess.
Remove the Fuselage Horizontal Nose (B1) from the sheet and spread Foam-Tac on the edge joining to the leading edge of the wing. Make sure you glue it in the with right side up and then wipe off any excess.
Remove the Fuselage Horizontal Rear Deck (B4) from the sheet and spread Foam-Tac on the small end and join it to the leading edge of the stabilizer/elevator (B3/B5) assembly. Make sure you glue it in the with right side up and then wipe off any excess.
Spread Foam-Tac on the front tab of the Fuselage Horizontal Rear Deck/stabilizer/elevator (B3/B4/B5) assembly and glue it onto the slot in the rear of the wing assembly and then wipe off any excess. You should now have the horizontal outline of the airframe face down on the building board.
Find the Fuselage Bottom (A1/A2) subassembly and spread glue on the bottom edge except on the tabs. Insert the tabs into the holes on the horizontal outline and prop it up so it is 90 degrees to it. Line up the motor mount area so it matches the vertical and horizontal cutouts.
The two rear fuselage stiffeners (E1) are glued to the bottom of the fuselage at a 45 degree angle to form a triangle cross-section with the fuselage bottom and horizontal outline and even with the rear fuselage bevel. This will prevent the tail from twisting in flight, so it is important to complete this step flat on the building board to maintain the alignment. There are small alignment holes and slightly larger ones paired in the rear of the wing and stabilizer. You can put round toothpicks into the smaller holes to help align where the edges of the fuselage stiffeners should go. The ends of the stiffeners should position between the larger holes. The large end of the fuselage stiffeners (E1) should face the front/wing end. Dry fit the fuselage stiffeners (E1) in place before spreading glue on both the edges and attach one of the fuselage stiffeners (E1) to each side of the rear fuselage. Make sure the edges are fully glued to the airframe and allow to fully dry. This is the primary structural support of the tail to keep it from twisting in flight.
With the glue dry, remove the toothpicks and turn over the airframe. Insert the 9g servo into the aileron servo pocket at the nose with the spline shaft towards the tail of the plane and glue in place (I normally put some Foam-Tac under the ears of the servo).
Take the straight nylon servo arm and position/align it into the plywood aileron servo bellcrank (bowtie shaped) concentric with the screw hole. If you are using the 9g servo included in our completer kit you will find alignment holes in the bellcrank that the two mounting screws in the servo hardware can be used to secure it. We have cut the center hole to be snug on the servo arm and attach under the arm. Set the remaining pushrod supports aside for when the pushrods are being made.
Spread glue on the bottom surface of the Fuselage Top assembly (A4/A5) and insert the tabs into the slots in the top of the airframe. Brace this vertically so it dries perpendicular to the horizontal surface.
Hinge the previously beveled Rudder (B2) to the previously beveled tail of the fuselage.
Glue the plywood motor mount into the nose cutout in the airframe being careful to align it so it is perpendicular. This is what sets your thrustline.
Find the quarter round gusset pieces (A3) and glue them in place as shown behind the firewall. This is important as it gives the firewall more glue surface and prevents the motor breaking off as easily. Use all 8 pieces, 2 per quadrant.
Glue the control horns into the slots in the surfaces. Notice that the elevator horn is different and has a flat front edge which rests against the elevator spar. All the horns glue in so the point at the front of them lines up with the hinge line which aligns the pushrod holes over the hinge. Spread a good amount of glue on both sides of the base of the horns to properly secure them in the slots.
Take the two 5g tail servos and mount them into the precut holes in the fuselage top. The splined shafts mount towards the tail of the plane and on the same size as the control surface horn. The rudder servo mount closest to the tail with the elevator servo closer to the front. As with the aileron servo, put glue under the servo tabs to secure them. You can also put some glue under the servo to further secure them. I use Foam-Tac for installation. Route the wires through the cutouts to below the wing.
Measure and cut the pushrods to be the distance from the servo splined post screw hole to the hinge line at the horn, minus 1/2". Clean the Z-bend wires and ends of the carbon rods with the sandpaper or alcohol to remove any possible oil or release agent. Save the extra scraps from the aileron pushrods for the aileron pivots later.
Assemble the pushrods with the Z-bend wires, pushrod supports and heat shrink tubing. Use the sandpaper and alcohol to clean and rough up the ends of the pushrods and the Z-bend wires. Do not glue the Z-bend wires at this point. For the tail servos, install two of the pushrod supports on each pushrod before putting the second Z-bend in place.
Find the aileron bellcrank assembled previously and take the two short aileron pushrods and hook one Z-bend end into the same hole on each aileron horn. At this point you want to decide how much throw you are going to want on the ailerons. The closer the hole is to the bottom, the more throw you will get. The top hole is aerobatic and the bottom hole is intense. You can adjust this somewhat later with the travel adjust on your transmitter. Tip the bellcrank vertical in the servo cutout and install the other Z-bend ends into the holes shown (outermost hole in the second row from the front). This eliminates the differential you would get with a straight servo arm giving you more axial rolls. Mount the bellcrank onto the servo spline shaft. Do not screw the arm on the servo yet. With the aileron bellcrank straight across the fuselage, adjust the level of the ailerons by sliding the Z-bend wires on the pushrods. With a piece of paper towel under the pushrod to not mar the paint, glue one end of the pushrod in place with CA glue. Check the aileron position again and glue the opposite end of the pushrod. Do this for both sides. Be careful not to spill any CA on the bellcrank or horns.
Find the straight servo arms in the 5g servo hardware baggies. Similar to the aileron pushrods, pick the appropriate hole you want on the tail horns and insert one end of the pushrod Z-bend. Put the Z-bend from other end of the pushrod into the outermost hole on the servo arm. Put the arm onto the servo spline shaft so that it stands vertical and adjust the Z-bends so the surface is centered. Do not worry about the pushrod supports at this point. Just let them hang free for now. With the pushrod length adjusted and the servo arm vertical, use CA to glue the Z-bend wires in place as you did with the aileron pushrods.
Using the mounting screws from the 5g servo hardware, attach the motor mount to the firewall.
Install the motor and ESC into the mount. Put the ESC/Motor wires on the same side of the fuselage as the servo wires so everything connects up to the receiver.
Find the two small plywood pivots and glue them to the end of the wings so the hole lines up with the extended hingeline. Take the scraps of the aileron pushrods and glue the small plastic dots to one end of them. You might need to sand a slight taper into the rod to fit well. Put a dab of Foam-Tac on the outside end of the dot to secure the rod. Then glue them to the top of the aileron counterbalance through the pivot and line up with the extended hingeline. Be careful not to get any glue on the plywood/rod/foam joint so it pivots freely.
Optional: If you are using our optional landing gear set, now is the time to attach the wheel pants (C3 and D3) to the landing gear struts. Spread Foam-Tac on the strut at the axle end and using the axle nut, align the wheel pant hole over the nut and set aside to dry. There is a flat part to the wheel pant which goes on the bottom, and the star on the pant should be upright. Install the wheel on the axle using the small rubber keeper supplied. Do not make it too snug or the wheels won't freely turn. Allow to dry and then attach the gear to the plywood mounting plate with the supplied screws. Glue the flat carbon strip provided to the front edge of the fake tailwheel.
Plug the ESC and servos into your receiver and bind and power on the radio. On each surface, adjust the horn on the servo so it is closest to the proper location. Check the servos to see if any need to be reversed. Using the provided screws, attach the arms to the servos. Use the radio subtrim feature to align the control surfaces. Attach a propeller to the motor using an o-ring and check for the proper direction of rotation. If the motor is backwards, swap any two wires on the ESC/motor connections. Unplug the flight battery and turn off the radio. Attach the Rx and ESC to the fuselage using Velcro. Using cable ties, gather up the excess servo leads to neaten the installation. I like to have all the components on one side of the fuselage and then use a long piece of Velcro on the other side for battery attachment. This allows you to position the battery forward or back to fine tune your CG. Tail heavy will hover a little better for example. Initial CG should be set to approximately 40mm behind the wing spar position and then adjusted through flight testing to your personal preference.