Wings

We located the main spars (hardwood) -to the lower left wing panel (above) and then the lower leading edge sheet (left) which we tacked to board. We then tacked then superglued the lower spar in position onto the leading edge sheet.

We found the trailing edge sheet (lower left) placed on plan. Using the wing ribs we put these parts together, (using packing wood under main spars) the ribs making the appropriate spacings, and check to make sure square before tacking main spars down onto plan

Placing the rib over the plan we could then mark on the rib where each mounting plate would be positioned.

4 mount plates, for both lower wings strut mounting points	Draw extended lines from fixing hole centres on plan,	Place plate on plan and using our extended lines to mark where fixing holes locate.	Drill holes	Mounting plates for strut fixing points ready to use.

Balsa USA Sopwith Pup Aileron & Wing Tip

Find the 'trailing edge sheet' pieces of balsa 1/8 x 1,7/8 x 18 (there are four of them, one for each wing). And aileron spar .

The bottom of the aileron spar has to be level with bottom of rear main spar.

As this is resting on packing pieces it was easy to just rest the aileron spar on these ensuring a match and glue together.

Locate the 4 aileron ribs (one of which is made of plywood the others balsa)

The 2nd rib in from the wing tip is plywood to take the fitting of the aileron servo horn (to operate the upper aileron - both ailerons are connected by a stick (vertical push rod) to move simultaneously and therefore requires a stronger material for mounting points)

Preparing to fit servo horn to ply rib. - We cut servo arms off leaving only one. (left)

Line up longest point of rib to point where rib intersects main wing.(as per pic below)

Glue on scrap piece of 1/8 ply to match area (approx) as shown on plan and glue in place. Mark centre line (making sure this matchs reinforce area on rib on plan) . Pic below

Line up cut servo horn with centre line as shown. Middle hole is level with top of rib and screw into position . Run thin CA glue around edge of horn to reinforce. (pic right)

Trailing edge sheet

Aileron Ribs

Locate the 2nd Aileron spar (for the actual aileron ) Pic far right.

Draw line 1/16" from the edge and chamfer to opposite edge. When placed in position this makes the spar sit at an angle that matchs those on the ribs.

With spar in position use end rib to locate our newly chamfered spar and the trailing edge sheet and pin sheet. Do same with first rib locating spar and sheet then pin trailing edge sheet. Locate two remaining ribs . Using setsquare to ensure ribs upright and glue.

Locate the off cut from the previously cut trailing edge strip. Locate that on rear of aileron and glue in position. (pic right)Mark on the two aeileron spars a line to correspond to the wingtip inner line and cut (pics below)

Locate the balsa wood piece for wing tip. Diverging from the instructions, we extended a line from the inner edge of the rear wing piece forward 2 - 3 inches. Place the corner of the wood on the front corner on the plane where the wing piece joins leading edge. Lay ruler over the wing piece and use drawn extended line to match up to with rear wing piece and mark wood.

Cut wood where marked. Reverse one half and match to plan as shown. Glue together. Offer glued pieces up to plan, place ruler to extend outmost aileron rib to mark line across lower end of wing tip.The turn ruler to match front edge of trailing edge strip and mark line to intersect with line previously drawn. (always taking care that rest of wing tip corresponds to plan. Cut all the way along the longer line and then across for the intersect line.

The wing tip needs to be rounded (otherwise it will have a point) Mark both ends either side of the area needing rounding and free hand draw radius. Then trim and sand to line. (you now have a rounded wing tip). Butt end of wing tip to trailing edge strip and outer rib and glue. Find one of the wing corner tips that you laminated earlier. Locate inside wing tip and trailing edge to make corner, glue in place.

Take the 1/4" square piece of wood for bracing the wing tip to the first main rib. Shape ends to fit into corner of rib and leading edge, mark point where it crosses wing tip and cut and glue into position. Similarly shape and cut and glue remaining piece.

Cut wing tip at join of two aileron spars (apply glue first) . Unpin and you have an aileron ! sand as necessary. Mark either side of outer corner as per wing tip to hand draw radius then sand for rounded edge.

Locate stiffener for wing struts rib (with metal fixing points on).

Cut to size for both sides of rib.

Mark and cut out recess for reinforcing plates on strut fixing points, fit and glue in position.

Find piece of wood for sheeting of first two (innermost) ribs. (we found it to be 1/8" thick although instructions say 3/32" ???) Lay sheet end on, mark and cut strips to size. Place on top and glue each piece down. Afterwards sand and trip flush to ribs. Repeat for underside of inner two ribs.