The rib are made of 6 mm depron. I'm using a technique derived from the "laser method". Pieces of depron are placed to form a comb. Afterward, the ribs are cut with a CNC hot wire. This method is very nice because (i) the ribs are cut very precisely and (ii) the remaining part will form a support for the assembly and for the sheeting.
The first rib and the one situated at the extremity of the sheath are reenforced with 100g/m2 glass fabric and epoxy.
After the cutting, the ribs and the longerons are glued with alyphatic glue.
The sheeting is made with 1.5mm balsa. On the next picture, the sheets of balsa are sanded to obtain straight borders, assembled with tape and glued with alyphatic glue.
The stab and the rudder are made with foam sheeted with 1.5mm balsa. The two servos for the stab are placed inside the stab.