Translations:KAVAN Orion A3 glider kit 930mm - Instruction manual/11/en

Wing centre section

The wing features an under-cambered wing section; it is to be built in two steps. At first, you are going to glue together the ribs, mains spar and leading edge on a flat working surface - and then you will add the trailing edge using the supplied jig in order to get everything right.
Pin down the bottom main spar 2 (6x2 mm spruce stick) laid over the supporting 5×1.5 mm balsa stick 1 on the building plan protected by a clear plastic film - refer to Det. A. Glue all the ribs 3 to the bottom spar as well as the outer ribs 6L and 6R - the bevelled side outwards (refer to Det. F-F).

Note: The centre ribs 9 will be glued later.

Glue together the 6×2mm spruce stick 4 and 6×4mm balsa stick 5 so that their sides match as well as possible (Det. G). Once the glue has cured, sand this side perfectly flat using No. 180 sandpaper.
Glue the prepared leading edge to the front of 3 and 6L/6R ribs.
Glue the 6×2 mm spruce top spar 10 into the notches in the ribs 3.
Remove the wing frame from the building plan and put glue into the notches in the left trailing edge 17L (we recommend using white wood glue as it gives you longer working time to set the trailing edge right and true). Attach the trailing edge to the ribs so the bottom of the trailing edge matches the bottom edge of the ribs. Before the glue sets; check the correct position of the trailing edge using the supplied jig 14 (Det. B).
Glue the right half of the trailing edge 17R in place in the same manner; finally, glue it to the left half 17L.
(If you are using cyano: Attach the trailing edge to the ribs, set it into the correct position using the jig 14 and only then apply the cyano to the joints.)
Lay down the wing centre section over the building plan and check if it is straight and true; before the glue sets you can carefully pin it down to the building board. In order to prevent any unwanted change of the wing profile, support the ribs with the balsa stick 1 near the trailing edge.
Glue the front bottom balsa sheeting 7 between the leading edge and the bottom spar 2; glue the rear bottom sheeting 8 between the main spar 2 and the trailing edge 17 (Det. G).
Glue two centre ribs 9 onto the bottom sheeting and then the top sheeting 11 and 12 over them (Det. G).
Cut the triangular gussets 13 from 1.5×8mm balsa stick and glue them into the corners.
Cut and sand flush to the bevelled end ribs 6L/6R the overlapping spars, leading and trailing edges 4+5, 2, 10, 17.