The wing is built over the plan in three sections and then joined with  1/16th plywood dihedral braces.  Start by pinning the center section bottom spar on the plan. There are five R1 ribs.  Take THREE of these and lay them on the spar as indicated on the plans.  The remaining two R1 ribs will be used in the outer wing panels.  Note the 1/2 inch holes drilled in the center ribs for wiring.  Stack the ribs and drill just ahead and behind the main spar.

Take the FOUR R1A ribs (the ones with the cutouts on the bottom rear) and lay them at the two outer positions on both ends of the center section.  This is the location of the nacelles and the cutouts are there for the blocks which will hold the nacelles in place.  In fact now is a good time to install these blocks.  They are 1/2 inch pieces of 3/16th sheet cut about 1/4 inch longer than the spacing between the ribs.  The outer portion will be trimmed back prior to joining the outer wing panels.

 

You should now have all rib positions covered for the center section.  Add the top spar.  Do not glue yet.  Cut an appropriate piece of 3/16th sheet and pin it into position at the rear of the ribs.  Note:  This 3/16th sheet should be slightly wider than the rib trailing edge and should be stood on end so that the trailing edge  is 3/16th. 

 

Align everything carefully, making sure that the two outer ribs are at 90 degrees to the building surface and 90 degrees to the wing trailing edge.  When things are aligned correctly glue in place with thin CA.

 

NOTE:  If you are using other glue types such as white glue, it is avisable to glue the various parts in place as they are placed over the plan.  Make sure things are aligned properly as they are placed, particularly the two outer ribs!!

 

Now cut a 1/2 inch wide strip of 3/16th balsa and glue into place at the leading edge. The center section is now complete and is removed from the plan to allow sanding the airfoil shape into both the leading and trailing edges.

Note the piece of 3/16th sheet between the two outer ribs.  This will be the location for the mounting bolt to hold the nacelle in place.

 

Note also the 1/16th sheet ahead of the spar between the same two ribs.  This sheet will have a hole cut in it to pass the motor wires down into the nacelle and allow the covering to adhere to the area around the hole.

 

Build the two outer panels using exactly the same method. NOTE: DO NOT GLUE RIB R1 IN PLACE AT THIS TIME AS IT WILL BE ALIGNED WHEN THE THREE PANELS ARE JOINED.

The ribs on these outer panels of course will taper toward the tip. Cut the two 1/8th balsa wing tips and glue in place. Cut the four (two for each side) wingtip braces from 1/8th scrap and glue into place.

Remove the two finished outer panels from the plan and plane or sand their leading and trailing edges to the proper airfoil shape.

 

Note that rib R1 is still not glued into place.  Position it loosely into the outer panel.  Reposition the center section over the plans and pin back onto the building board.  Use a block or similar to raise the outer panel tips 1.5 inches from the work surface.  Carefully sand both the lower and upper spar ends so that they align exactly with the spars on the center panel.  You will have to sand more from the upper spar to make the alignment.

 

When things line up well, slide rib R1 into place alongside it's R1A cousin and glue everything into place.  This picture shows clamps used when gluing.  Although not shown in the pictures, small triangles of 3/16th sheet can be glued at the leading and trailing edge to strengthen the dihedral joint.  Check the plans for location.

 

 

Let's start by building the nacelles.  Cut FOUR 3/32ND sheet nacelle sides from the template on the plan.  You are making TWO nacelles and need TWO right and left sides.  Note the 1/2 inch cutouts for the nacelle mounting blocks.

 

Using 3/16th square balsa stripped from 3/16th sheet add the doublers only on the top front of each nacelle side.  Don't forget LEFT AND RIGHT.  Trim the excess 3/16th stick to match the airfoil top.

 

Cut the TWO firewalls from 1/8th balsa sheet and CAREFULLY cut the square hole for the motor mounting stick.  This should be a snug fit for the standard motor mounting stick on the GWS geared motors.

 

Cut FOUR rear nacelle formers from 1/8th liteply.  Note that ONE of these formers will be used in each nacelle construction and the other two reserved for later landing gear mounting. Again, the cutout in these formers should be a snug fit for the motor mounting stick.

 

 

Because the motors are mounted with a sideways offset to keep the nacelle profile slim, you need to be careful and glue the formers into both nacelles with the mounting stick coutouts at the correct location.  I felt it was better to have the motor weight closer to the center line and glued the formers in place accordingly.  Check the photos and plans to see what I mean here.

The nacelles will later be sheeted on the top front from the airfoil forward and on the bottom to about three quarters of the way back.  The TOP portion which sits right under the wing is left unsheeted as is the rear.  The allows easy access to the motor wiring simply by dropping the nacelles off the wing, and to the landing gear installation screws from the rear.  The motor can be easily pulled directly out the nacelle front and is held in place by a single screw through the gearbox into the mounting stick.  This screw is accessed through a small hole cut in the bottom sheeting.

The nacelle tops will be rounded slightly when sheeted.  I used small scrap balsa pieces to double up on the inside of the nacelle nose.  Too much here will interfere with the mounting of the motors.

Cut the two 1/16th Ply dihedral braces.  Carefully cut through two ribs at the dihedral joint and glue in the ply brace.  Note the two 1/8th dowells that support the nacelle front.  The dowells will pass back through the ply brace.

The wing tips and their triangle supports can now be cut from 1/8th balsa sheet and glued to each wing tip.  It is not necessary, but lightening holes can be cut in the tips as shown here.

Glue a section of one inch aileron stock to the trailing edge on the center section only.  Depending on your aileron stock, you may or may not have to plane a bit from the front edge to get the proper airfoil fit.  Two more sections of one inch aileron stock make up the actual ailerons themselves and will be fitted during final construction.

 

Cut the nose former and nosewheel mounting parts from 1/8th liteply and assemble as shown. The .078 nose gear will be positioned in the small holes in the tabs and held in place with wheel collars. The top collar is actually the steering arm after part of a metal clevis was cut away and soldered to the wheel collar.

Cut the two fuselage sides from 3/32nd balsa.  Build formers F1 and F2 over the plans using sheet 3/16th balsa and 3/16th square sticks stripped from 3/16th sheet.  Note the holes for the wing mounting dowells in former F1.  Measure and mark a vertical center line on each former.

 

Remember to make a left and right fuselage side.  As shown on the plans use 3/16th square stick for doublers along the fuselage bottom and also on the top aft of the wing saddle.  Use 3/8th triangle stock to make doublers on the top nose section.  Cut saw grooves in the triangle stock to allow for easier bending.

 

When you have a left and right side finished, place one side on the plan, and glue formers F1 and F2 in place using a square for alignment.  Now place that side and formers upright on the plan over the straight line on the plan bottom.  Place the other fuselage side in position and use some scrap wood pinned outside each side on the workbench to keep things aligned.  When satisfied with the alignment glue the second side to the formers.  Install both 1/16th wing saddle doublers.

 

Now the tail can be pulled together and glued taking care to keep things lined up with the centerline.  The finished nose former can now be glued in place, again watching the alignment.

 

Test fit the fin (do not glue) and add another former made from scrap 3/16th across the fuse  (top and bottom) where the fin will be installed in the fuselage

Build the stab, elevator, fin and rudder over the plans using 3/16th sheet and 3/16th square sticks. 

 

Note that the two leading edge sticks in the fin are grooved to accomodate a Sullivan Mini pushrod cable for the elevator.  After grooving both pieces, cut an appropriate length of cable and glue it between the two pieces when assembling the fin.

 

The cable passes up over a groove in the fin top (a separate piece added after the stab is glued in place) and back to the control horn in the top of the elevator.

When the stab and fin have been assembled, place the stab on a flat surface and align and glue the fin in place making sure the joint is square.  Use small pieces of 1/4 inch triangle stock at this joint for strength.

A tapered triangle of scrap 3/16th sheet is installed on the fuse bottom to allow support for the fin. Glue this so that it protrudes slightly from the bottom and plane or sand to the fuselage shape.

The nose block is made up of sheets 3/16th glued together and then carved to shape.  It covers the landing gear mount and pushrod and has to be hollowed to fit. 

 

Once glued together it is tack glued to the fuselage and carved to shape.  Some carving of the interior might need to be done when installing the nose gear during final assembly.

Remove the wing and install 3/16th square rails to support the 1/16th cross grain balsa battery tray.  This installation stiffens up the fuselage considerably.  The bottom view is shown above.

Before installing the tail feathers the wing hold down must be set up so there is a reference to set the stab incidence.  Place the wing into position and using the holes in former F1 locate and drill the holes in the wing leading edge for the 1/8th hold down dowells.  We use bamboo skewers obtained at the local supermarket and the sharp point is easily used to mark the hole locations in the wing.  Note that the dowells go back through the shear webbing.

 

Note this picture shows the nosegear mount rubber banded into place and not yet glued into the fuselage.  It also does not show the 3/8th triangle stock used to round the top front of the fuselage nor the aileron stock trailing edge.

Place some waxed paper between the wing trailing edge and fuselage and glue the sub ribs/fuselage fairings into place.  A piece of 3/32nd sheet makes up the back of the fairing and 1/16th sheet will be glued into place on the top. 

 

Note the scrap balsa block used to build up the area around the wing hold down bolt so that tightening it here does not squeeze down the fairing top.

After installing the dowells the nose TOP can be sheeted and carved.

To install the stab with the proper incidence, fasten the wing tightly to the fuselage.  Place the plane on a flat bench and weigh it down so that the flat section on the front underside contacts the workbench.

 

Place an incidence meter on the wing and if your workbench is flat the meter should read zero.  If your bench is a bit off note the reading.

 

Place the fin with attached stab at the proper spot in the fuse and using the incidence meter make sure that the reading is the same as the wing.  When satisfied with the alignment glue the fin into place. 

 

Use some scrap 3/16th sheet to shim the fin with the fuselage sides on the top.

Now the fuselage top from the wing saddle back can be sheeted with 1/16th balsa and sanded to shape.

 

The fuse bottom is NOT sheeted.  We opted to install the motor batteries through the wing saddle to avoid the extra weight of a hatch structure.

Make two of each rib R2 through R7.  Make four of R1A and five R1.  Stack all R1 and R1A together and drill a half inch hole just before and after the main spar to pass the wiring.